Refactor: Migrate unwrap calls to AppError in MCP handlers

server/src/error.rs

@@ -103,3 +103,15 @@ mod tests {
         assert_eq!(err.to_string(), "Bad Request: test");
     }
 }
+
+impl From<String> for AppError {
+    fn from(msg: String) -> Self {
+        AppError::Internal(msg)
+    }
+}
+
+impl From<&str> for AppError {
+    fn from(msg: &str) -> Self {
+        AppError::Internal(msg.to_string())
+    }
+}

server/src/handlers/ast.rs

@@ -21,13 +21,13 @@ impl McpTool for ReadFileSkeletonHandler {
         )
     }
 
-    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> crate::error::Result<String> {
         let tool_args: ReadFileSkeletonTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         
         let file_path = tool_args.file_path.clone();
-        let result = tokio::task::spawn_blocking(move || -> Result<String, String> {
+        let result = tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
             let code = std::fs::read_to_string(&file_path)
-                .map_err(|e| format!("Failed to read file: {}", e))?;
+                .map_err(|e| crate::error::AppError::Internal(format!("Failed to read file: {}", e)))?;
                 
             let mut parser = Parser::new();
             
@@ -49,7 +49,7 @@ impl McpTool for ReadFileSkeletonHandler {
             
             parser.set_language(&language.into()).map_err(|e| e.to_string())?;
             
-            let tree = parser.parse(&code, None).ok_or("Failed to parse code")?;
+            let tree = parser.parse(&code, None).ok_or_else(|| crate::error::AppError::Internal("Failed to parse code".to_string()))?;
             let mut result_skeleton = String::new();
             
             fn extract_skeleton(node: Node, code: &str, out: &mut String, depth: usize) {
@@ -97,7 +97,7 @@ impl McpTool for ReadFileSkeletonHandler {
             }
         })
         .await
-        .map_err(|e| format!("Task panic: {}", e))??;
+        .map_err(|e| crate::error::AppError::Internal(format!("Task panic: {}", e)))??;
 
         Ok(result)
     }
@@ -119,13 +119,13 @@ impl McpTool for ReplaceAstNodeHandler {
         )
     }
 
-    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> crate::error::Result<String> {
         let tool_args: ReplaceAstNodeTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         
         let file_path = tool_args.file_path.clone();
-        let result = tokio::task::spawn_blocking(move || -> Result<String, String> {
+        let result = tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
             let code = std::fs::read_to_string(&file_path)
-                .map_err(|e| format!("Failed to read file: {}", e))?;
+                .map_err(|e| crate::error::AppError::Internal(format!("Failed to read file: {}", e)))?;
                 
             let mut parser = Parser::new();
             
@@ -142,11 +142,11 @@ impl McpTool for ReplaceAstNodeHandler {
                 "c" | "h" => tree_sitter_c::LANGUAGE,
                 "cpp" | "cc" | "cxx" | "hpp" | "hxx" => tree_sitter_cpp::LANGUAGE,
                 "go" => tree_sitter_go::LANGUAGE,
-                _ => return Err(format!("Unsupported language for AST replacement: {}", ext)),
+                _ => return Err(crate::error::AppError::Internal(format!("Unsupported language for AST replacement: {}", ext))),
             };
             
             parser.set_language(&language.into()).map_err(|e| e.to_string())?;
-            let tree = parser.parse(&code, None).ok_or("Failed to parse code")?;
+            let tree = parser.parse(&code, None).ok_or_else(|| crate::error::AppError::Internal("Failed to parse code".to_string()))?;
             
             // Search for the node
             fn find_node<'a>(node: Node<'a>, code: &str, target_type: &str, target_name: &str) -> Option<Node<'a>> {
@@ -187,11 +187,11 @@ impl McpTool for ReplaceAstNodeHandler {
                 std::fs::write(&file_path, new_file_content).map_err(|e| e.to_string())?;
                 Ok(format!("Successfully replaced node {} of type {} in {}", tool_args.node_name, tool_args.node_type, file_path))
             } else {
-                Err(format!("Could not find node {} of type {}", tool_args.node_name, tool_args.node_type))
+                Err(crate::error::AppError::Internal(format!("Could not find node {} of type {}", tool_args.node_name, tool_args.node_type)))
             }
         })
         .await
-        .map_err(|e| format!("Task panic: {}", e))??;
+        .map_err(|e| crate::error::AppError::Internal(format!("Task panic: {}", e)))??;
 
         Ok(result)
     }

server/src/handlers/env.rs

@@ -20,7 +20,7 @@ impl McpTool for UpdateEnvFingerprintHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: UpdateEnvFingerprintTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.env_fingerprints.modify(|fps| {
@@ -54,14 +54,14 @@ impl McpTool for ReadEnvFingerprintHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ReadEnvFingerprintTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state
             .env_fingerprints
             .read_with(|fps| fps.get(&req.namespace).cloned());
         if let Some(fp) = data {
-            let data = serde_json::to_string(&fp).map_err(|e| e.to_string())?;
+            let data = Ok::<String, crate::error::AppError>(serde_json::to_string(&fp)?)?;
             Ok(data)
         } else {
             Ok("{}".to_string())
@@ -84,7 +84,7 @@ impl McpTool for LogEnvRequirementHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: LogEnvRequirementTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.env_requirements.modify(|reqs| {
             reqs.retain(|r| !(r.namespace == req.namespace && r.key == req.key));
@@ -114,7 +114,7 @@ impl McpTool for RegisterEnvironmentHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: RegisterEnvironmentTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.environments.modify(|envs| {
@@ -147,7 +147,7 @@ impl McpTool for GetEnvironmentDetailsHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: GetEnvironmentDetailsTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.environments.read_with(|envs| {
@@ -155,7 +155,7 @@ impl McpTool for GetEnvironmentDetailsHandler {
                 .iter()
                 .filter(|e| e.namespace == req.namespace)
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -180,14 +180,13 @@ mod tests {
             }
         });
 
-        let res = update_handler.execute(args, state.clone()).await.unwrap();
+        let res = update_handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res, "Env fingerprint updated");
 
         let read_handler = ReadEnvFingerprintHandler;
         let res2 = read_handler
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res2.contains("rustc"));
         assert!(res2.contains("1.70.0"));
     }
@@ -212,8 +211,7 @@ mod tests {
         let handler = GetEnvironmentDetailsHandler;
         let res = handler
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
 
         assert!(res.contains("global"));
     }
@@ -232,7 +230,7 @@ mod tests {
             "context": "For database access",
             "namespace": "global"
         });
-        let res1 = req_handler.execute(args_req, state.clone()).await.unwrap();
+        let res1 = req_handler.execute(args_req, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res1, "Env requirement logged");
 
         let reg_handler = RegisterEnvironmentHandler;
@@ -243,14 +241,13 @@ mod tests {
             "requires_vpn": true,
             "namespace": "global"
         });
-        let res2 = reg_handler.execute(args_reg, state.clone()).await.unwrap();
+        let res2 = reg_handler.execute(args_reg, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res2, "Environment registered");
 
         let get_handler = GetEnvironmentDetailsHandler;
         let res3 = get_handler
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res3.contains("prod.local"));
         assert!(!res3.is_empty());
     }

server/src/handlers/git.rs

@@ -21,10 +21,10 @@ impl McpTool for GetActiveWorktreeContextHandler {
         )
     }
 
-    async fn execute(&self, _args: Value, _state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, _args: Value, _state: Arc<MemoryState>) -> crate::error::Result<String> {
-        let result = tokio::task::spawn_blocking(move || -> Result<Value, String> {
+        let result = tokio::task::spawn_blocking(move || -> crate::error::Result<serde_json::Value> {
             let cwd = env::current_dir().map_err(|e| e.to_string())?;
-            let repo = git2::Repository::discover(&cwd).map_err(|e| format!("Not in a git repository: {}", e))?;
+            let repo = git2::Repository::discover(&cwd).map_err(|e| crate::error::AppError::Internal(format!("Not in a git repository: {}", e)))?;
             
             let mut branch_name = String::new();
             if let Ok(head) = repo.head()
@@ -70,8 +70,8 @@ impl McpTool for GetActiveWorktreeContextHandler {
             }))
         })
         .await
-        .map_err(|e| format!("Task panic: {}", e))??;
+        .map_err(|e| crate::error::AppError::Internal(format!("Task panic: {}", e)))??;
 
-        Ok(serde_json::to_string_pretty(&result).unwrap())
+        Ok::<String, crate::error::AppError>(serde_json::to_string_pretty(&result)?)
     }
 }

server/src/handlers/graph.rs

@@ -24,7 +24,7 @@ impl McpTool for QueryGraphPathHandler {
         crate::mcp::tool_def::<QueryGraphPathTool>("query_graph_path", "Execute query_graph_path")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: crate::tools::QueryGraphPathTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.read_graph(|graph| {
@@ -115,7 +115,7 @@ impl McpTool for CreateEntitiesHandler {
         crate::mcp::tool_def::<CreateEntitiesTool>("create_entities", "Execute create_entities")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: CreateEntitiesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut inserted = Vec::new();
         state.modify_graph(|g| {
@@ -146,7 +146,7 @@ impl McpTool for CreateRelationsHandler {
         crate::mcp::tool_def::<CreateRelationsTool>("create_relations", "Execute create_relations")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: CreateRelationsTool = match serde_json::from_value(args.clone()) {
             Ok(r) => r,
             Err(e) => {
@@ -155,12 +155,12 @@ impl McpTool for CreateRelationsHandler {
                     || err_msg.contains("missing field `to`")
                     || err_msg.contains("missing field `relation_type`")
                 {
-                    return Err(format!(
+                    return Err(crate::error::AppError::Internal(format!(
                         "Schema error: {}. Note that the relation schema strictly uses 'from', 'to', and 'relation_type' (not 'source', 'target', or 'relationType'). Please correct your tool call arguments.",
                         err_msg
-                    ));
+                    )));
                 }
-                return Err(err_msg);
+                return Err(err_msg.into());
             }
         };
         let mut missing_nodes = std::collections::HashSet::new();
@@ -184,10 +184,9 @@ impl McpTool for CreateRelationsHandler {
         });
         if !missing_nodes.is_empty() {
             let missing: Vec<_> = missing_nodes.into_iter().collect();
-            return Err(format!(
+            return Err(crate::error::AppError::Internal(format!(
                 "Error: Relations dropped due to missing entities: {}",
-                missing.join(", ")
+                missing.join(", "))));
-            ));
         }
         Ok("Relations created".to_string())
     }
@@ -205,7 +204,7 @@ impl McpTool for AddObservationsHandler {
         crate::mcp::tool_def::<AddObservationsTool>("add_observations", "Execute add_observations")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: AddObservationsTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut missing_entities = Vec::new();
         state.modify_graph(|g| {
@@ -218,10 +217,9 @@ impl McpTool for AddObservationsHandler {
             }
         });
         if !missing_entities.is_empty() {
-            return Err(format!(
+            return Err(crate::error::AppError::Internal(format!(
                 "Error: Observations dropped for missing entities: {}",
-                missing_entities.join(", ")
+                missing_entities.join(", "))));
-            ));
         }
         Ok("Observations added".to_string())
     }
@@ -239,7 +237,7 @@ impl McpTool for DeleteEntitiesHandler {
         crate::mcp::tool_def::<DeleteEntitiesTool>("delete_entities", "Execute delete_entities")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: DeleteEntitiesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let to_delete: std::collections::HashSet<_> = req.entity_names.into_iter().collect();
         let mut missing = Vec::new();
@@ -255,10 +253,9 @@ impl McpTool for DeleteEntitiesHandler {
         });
 
         if !missing.is_empty() {
-            return Err(format!(
+            return Err(crate::error::AppError::Internal(format!(
                 "Error: Entities not found: {}. Please use the search_nodes or read_graph tools to verify the exact entity names.",
-                missing.join(", ")
+                missing.join(", "))));
-            ));
         }
 
         let idx = state.get_search_index();
@@ -284,7 +281,7 @@ impl McpTool for DeleteObservationsHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: DeleteObservationsTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut missing = Vec::new();
@@ -299,10 +296,9 @@ impl McpTool for DeleteObservationsHandler {
             }
         });
         if !missing.is_empty() {
-            return Err(format!(
+            return Err(crate::error::AppError::Internal(format!(
                 "Error: Entities not found: {}. Please use the search_nodes or read_graph tools to verify the exact entity names.",
-                missing.join(", ")
+                missing.join(", "))));
-            ));
         }
         Ok("Observations deleted".to_string())
     }
@@ -320,7 +316,7 @@ impl McpTool for DeleteRelationsHandler {
         crate::mcp::tool_def::<DeleteRelationsTool>("delete_relations", "Execute delete_relations")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: DeleteRelationsTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut missing_count = 0;
         state.modify_graph(|master| {
@@ -330,10 +326,10 @@ impl McpTool for DeleteRelationsHandler {
             missing_count = to_rem.len() - (initial_len - master.relations.len());
         });
         if missing_count > 0 {
-            return Err(format!(
+            return Err(crate::error::AppError::Internal(format!(
                 "Error: {} relation(s) not found in graph. Please verify exact relation properties using read_graph.",
                 missing_count
-            ));
+            )));
         }
         Ok("Relations deleted".to_string())
     }
@@ -351,9 +347,9 @@ impl McpTool for ReadGraphHandler {
         crate::mcp::tool_def::<ReadGraphTool>("read_graph", "Execute read_graph")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ReadGraphTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
-        let data = state.read_graph(|full| -> Result<String, String> {
+        let data = state.read_graph(|full| -> crate::error::Result<String> {
             if let Some(ns) = req.namespace {
                 let mut filtered = BorrowedGraph::default();
                 for (k, v) in &full.entities {
@@ -366,9 +362,9 @@ impl McpTool for ReadGraphHandler {
                         filtered.relations.push(r);
                     }
                 }
-                serde_json::to_string(&filtered).map_err(|e| e.to_string())
+                Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
             } else {
-                serde_json::to_string(full).map_err(|e| e.to_string())
+                Ok::<String, crate::error::AppError>(serde_json::to_string(full)?)
             }
         })?;
         Ok(data)
@@ -387,7 +383,7 @@ impl McpTool for SearchNodesHandler {
         crate::mcp::tool_def::<SearchNodesTool>("search_nodes", "Execute search_nodes")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: SearchNodesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let matches = if let Ok(idx) = state.search_index.read() {
             idx.search(&req.query, req.namespace.as_deref())
@@ -396,7 +392,7 @@ impl McpTool for SearchNodesHandler {
             vec![]
         };
 
-        let data = state.read_graph(|full| -> Result<String, String> {
+        let data = state.read_graph(|full| -> crate::error::Result<String> {
             let mut result = BorrowedGraph::default();
             for (id, doc_type, _, _, _) in &matches {
                 if doc_type == "entity"
@@ -405,7 +401,7 @@ impl McpTool for SearchNodesHandler {
                     result.entities.insert(id, e);
                 }
             }
-            serde_json::to_string(&result).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&result)?)
         })?;
         Ok(data)
     }
@@ -423,9 +419,9 @@ impl McpTool for OpenNodesHandler {
         crate::mcp::tool_def::<OpenNodesTool>("open_nodes", "Execute open_nodes")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: OpenNodesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
-        let data = state.read_graph(|full| -> Result<String, String> {
+        let data = state.read_graph(|full| -> crate::error::Result<String> {
             let targets: HashSet<&str> = req.names.iter().map(|s| s.as_str()).collect();
             let mut result = BorrowedGraph::default();
             let mut connected: HashSet<&str> = HashSet::new();
@@ -443,7 +439,7 @@ impl McpTool for OpenNodesHandler {
                     result.entities.insert(name, e);
                 }
             }
-            serde_json::to_string(&result).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&result)?)
         })?;
         Ok(data)
     }
@@ -461,7 +457,7 @@ impl McpTool for VisualizeGraphHandler {
         crate::mcp::tool_def::<VisualizeGraphTool>("visualize_graph", "Execute visualize_graph")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: VisualizeGraphTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let query = req.query.unwrap_or_default();
         let mut output = state.read_graph(|full| {
@@ -550,7 +546,7 @@ impl McpTool for CondenseEntityHandler {
         crate::mcp::tool_def::<CondenseEntityTool>("condense_entity", "Execute condense_entity")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: CondenseEntityTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut missing = false;
         state.modify_graph(|master| {
@@ -561,10 +557,10 @@ impl McpTool for CondenseEntityHandler {
             }
         });
         if missing {
-            return Err(format!(
+            return Err(crate::error::AppError::Internal(format!(
                 "Error: Entity '{}' not found. Please verify the exact entity name using search_nodes.",
                 req.entity_name
-            ));
+            )));
         }
         Ok("Entity condensed".to_string())
     }
@@ -582,7 +578,7 @@ impl McpTool for MergeEntitiesHandler {
         crate::mcp::tool_def::<MergeEntitiesTool>("merge_entities", "Execute merge_entities")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: MergeEntitiesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut missing = false;
         state.modify_graph(|master| {
@@ -616,10 +612,10 @@ impl McpTool for MergeEntitiesHandler {
             });
         });
         if missing {
-            return Err(format!(
+            return Err(crate::error::AppError::Internal(format!(
                 "Error: Source entity '{}' not found. Please verify the exact entity name using search_nodes.",
                 req.source_entity
-            ));
+            )));
         }
         Ok("Entities merged".to_string())
     }
@@ -637,7 +633,7 @@ impl McpTool for FindOrphansHandler {
         crate::mcp::tool_def::<FindOrphansTool>("find_orphans", "Execute find_orphans")
     }
 
-    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let orphans = state.read_graph(|full| {
             let mut connected = std::collections::HashSet::new();
             for r in &full.relations {
@@ -650,7 +646,7 @@ impl McpTool for FindOrphansHandler {
                 .cloned()
                 .collect::<Vec<String>>()
         });
-        let data = serde_json::to_string(&orphans).map_err(|e| e.to_string())?;
+        let data = Ok::<String, crate::error::AppError>(serde_json::to_string(&orphans)?)?;
         Ok(data)
     }
 }
@@ -675,7 +671,7 @@ mod tests {
             ]
         });
 
-        let res = create_handler.execute(args, state.clone()).await.unwrap();
+        let res = create_handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res, "Entities created");
 
         // Ensure graph contains the entity
@@ -720,7 +716,7 @@ mod tests {
                 {"from": "A", "to": "B", "relation_type": "knows"}
             ]
         });
-        let res = handler.execute(args, state.clone()).await.unwrap();
+        let res = handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res, "Relations created");
 
         // Test semantic LLM schema feedback (User request)
@@ -759,28 +755,25 @@ mod tests {
                 {"entity_name": "A", "contents": ["Obs 1", "Obs 2"]}
             ]
         });
-        let res1 = add_obs.execute(args_obs, state.clone()).await.unwrap();
+        let res1 = add_obs.execute(args_obs, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res1, "Observations added");
 
         let read_graph = ReadGraphHandler;
         let res2 = read_graph
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res2.contains("Obs 1"));
         assert!(res2.contains("Obs 2"));
 
         let del_entity = DeleteEntitiesHandler;
         let res4 = del_entity
             .execute(json!({"entity_names": ["A"]}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res4, "Entities deleted");
 
         let res5 = read_graph
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(!res5.contains("A"));
     }
 
@@ -798,8 +791,7 @@ mod tests {
         });
         create_handler
             .execute(args_ent, state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
 
         let rel_handler = CreateRelationsHandler;
         let args_rel = json!({
@@ -807,28 +799,25 @@ mod tests {
                 {"from": "X", "to": "Y", "relation_type": "depends_on", "namespace": "global"}
             ]
         });
-        rel_handler.execute(args_rel, state.clone()).await.unwrap();
+        rel_handler.execute(args_rel, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
 
         let read_handler = ReadGraphHandler;
         let res_read = read_handler
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res_read.contains("X"));
         assert!(res_read.contains("depends_on"));
 
         let open_handler = OpenNodesHandler;
         let res_open = open_handler
             .execute(json!({"names": ["X"]}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res_open.contains("Y"));
 
         let viz_handler = VisualizeGraphHandler;
         let res_viz = viz_handler
             .execute(json!({"query": "X"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(!res_viz.is_empty());
 
         let condense = CondenseEntityHandler;
@@ -837,8 +826,7 @@ mod tests {
                 json!({"entity_name": "X", "summarized_observations": ["X condensed"]}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res_cond, "Entity condensed");
 
         let merge = MergeEntitiesHandler;
@@ -847,12 +835,11 @@ mod tests {
                 json!({"source_entity": "X", "target_entity": "Y"}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res_merge, "Entities merged");
 
         let orphans = FindOrphansHandler;
-        let res_orphans = orphans.execute(json!({}), state.clone()).await.unwrap();
+        let res_orphans = orphans.execute(json!({}), state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(!res_orphans.contains("Y"));
     }
 }

server/src/handlers/logs.rs

@@ -22,10 +22,10 @@ impl McpTool for WatchProcessLogsHandler {
         )
     }
 
-    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> crate::error::Result<String> {
         let tool_args: WatchProcessLogsTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         if !std::path::Path::new(&tool_args.file_path).exists() {
-            return Err(format!("File does not exist: {}", tool_args.file_path));
+            return Err(crate::error::AppError::Internal(format!("File does not exist: {}", tool_args.file_path)));
         }
         Ok(format!("Started watching logs for {}", tool_args.file_path))
     }
@@ -46,11 +46,11 @@ impl McpTool for GetRecentLogsHandler {
         )
     }
 
-    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> crate::error::Result<String> {
         let tool_args: GetRecentLogsTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         
-        let result = tokio::task::spawn_blocking(move || -> Result<String, String> {
+        let result = tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
-            let mut file = File::open(&tool_args.file_path).map_err(|e| format!("Failed to open file: {}", e))?;
+            let mut file = File::open(&tool_args.file_path).map_err(|e| crate::error::AppError::Internal(format!("Failed to open file: {}", e)))?;
             let len = file.metadata().map_err(|e| e.to_string())?.len();
             
             let read_size = std::cmp::min(16 * 1024, len);
@@ -69,7 +69,7 @@ impl McpTool for GetRecentLogsHandler {
             Ok(recent_lines)
         })
         .await
-        .map_err(|e| format!("Task panic: {}", e))??;
+        .map_err(|e| crate::error::AppError::Internal(format!("Task panic: {}", e)))??;
 
         Ok(result)
     }

server/src/handlers/meta.rs

@@ -18,7 +18,7 @@ impl McpTool for LogDecisionHandler {
         crate::mcp::tool_def::<LogDecisionTool>("log_decision", "Execute log_decision")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: LogDecisionTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
 
         let idx = state.get_search_index();
@@ -68,7 +68,7 @@ impl McpTool for QueryDecisionsHandler {
         crate::mcp::tool_def::<QueryDecisionsTool>("query_decisions", "Execute query_decisions")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: QueryDecisionsTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.adrs.read_with(|adrs| {
             let filtered: Vec<_> = adrs
@@ -83,7 +83,7 @@ impl McpTool for QueryDecisionsHandler {
                     }
                 })
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -104,7 +104,7 @@ impl McpTool for DeleteDecisionHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: crate::tools::DeleteDecisionTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut found = false;
@@ -119,7 +119,7 @@ impl McpTool for DeleteDecisionHandler {
             state.rebuild_index().await;
             Ok("Decision deleted successfully".to_string())
         } else {
-            Err("Decision not found".to_string())
+            Err(crate::error::AppError::Internal("Decision not found".to_string()))
         }
     }
 }
@@ -136,7 +136,7 @@ impl McpTool for LogErrorFixHandler {
         crate::mcp::tool_def::<LogErrorFixTool>("log_error_fix", "Execute log_error_fix")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: LogErrorFixTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let text_to_embed = format!("Signature: {}\nSolution: {}", req.signature, req.solution);
         let embedding = crate::embedding::generate_embedding_async(text_to_embed).await.ok();
@@ -169,7 +169,7 @@ impl McpTool for SearchErrorFixesHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: SearchErrorFixesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let q = req.query;
         let data = state.error_fixes.read_with(|fixes| {
@@ -180,7 +180,7 @@ impl McpTool for SearchErrorFixesHandler {
                         || contains_ignore_ascii_case(&f.solution, &q)
                 })
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -198,7 +198,7 @@ impl McpTool for LogCodeChangeHandler {
         crate::mcp::tool_def::<LogCodeChangeTool>("log_code_change", "Execute log_code_change")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: LogCodeChangeTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.ledger.modify(|ledger| {
             ledger.push(CodeChange {
@@ -228,10 +228,10 @@ impl McpTool for QueryRecentChangesHandler {
         )
     }
 
-    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let data = state
             .ledger
-            .read_with(|l| serde_json::to_string(l).map_err(|e| e.to_string()))?;
+            .read_with(|l| Ok::<String, crate::error::AppError>(serde_json::to_string(l)?))?;
         Ok(data)
     }
 }
@@ -248,7 +248,7 @@ impl McpTool for LearnPreferenceHandler {
         crate::mcp::tool_def::<LearnPreferenceTool>("learn_preference", "Execute learn_preference")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: LearnPreferenceTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.prefs.modify(|prefs| {
             prefs.insert(
@@ -276,10 +276,10 @@ impl McpTool for ReadPreferencesHandler {
         crate::mcp::tool_def::<ReadPreferencesTool>("read_preferences", "Execute read_preferences")
     }
 
-    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         state
             .prefs
-            .read_with(|prefs| serde_json::to_string(prefs).map_err(|e| e.to_string()))
+            .read_with(|prefs| Ok::<String, crate::error::AppError>(serde_json::to_string(prefs)?))
     }
 }
 
@@ -295,7 +295,7 @@ impl McpTool for LogTechDebtHandler {
         crate::mcp::tool_def::<LogTechDebtTool>("log_tech_debt", "Execute log_tech_debt")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: LogTechDebtTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let text_to_embed = format!("Description: {}\nIdeal Solution: {}", req.description, req.ideal_solution);
         let embedding = crate::embedding::generate_embedding_async(text_to_embed).await.ok();
@@ -331,7 +331,7 @@ impl McpTool for ResolveTechDebtHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ResolveTechDebtTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut found = false;
         state.tech_debts.modify(|debts| {
@@ -346,10 +346,7 @@ impl McpTool for ResolveTechDebtHandler {
         if found {
             Ok("Tech debt resolved".to_string())
         } else {
-            Err(
+            Err(crate::error::AppError::Internal("Tech debt not found. Please verify the tech debt ID using list_tech_debt.".to_string()))
-                "Tech debt not found. Please verify the tech debt ID using list_tech_debt."
-                    .to_string(),
-            )
         }
     }
 }
@@ -366,7 +363,7 @@ impl McpTool for ListTechDebtHandler {
         crate::mcp::tool_def::<ListTechDebtTool>("list_tech_debt", "Execute list_tech_debt")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ListTechDebtTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.tech_debts.read_with(|debts| {
             let filtered: Vec<_> = debts
@@ -375,7 +372,7 @@ impl McpTool for ListTechDebtHandler {
                     d.namespace == req.namespace && (req.include_resolved || !d.is_resolved)
                 })
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -393,7 +390,7 @@ impl McpTool for OmniSearchHandler {
         crate::mcp::tool_def::<OmniSearchTool>("omni_search", "Execute omni_search")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: OmniSearchTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let limit = req.limit.unwrap_or(5);
         let include_body = req.include_body.unwrap_or(false);
@@ -403,10 +400,10 @@ impl McpTool for OmniSearchHandler {
         {
             Ok(m) => m,
             Err(e) => {
-                return Err(format!(
+                return Err(crate::error::AppError::Internal(format!(
                     "Search query failed (possibly malformed Lucene syntax). Error: {}",
                     e
-                ));
+                )));
             }
         };
         // tracing::info!("OMNI SEARCH MATCHES: {:?}", matches);
@@ -614,7 +611,7 @@ impl McpTool for GetProjectHealthHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: GetProjectHealthTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let active_tasks = state
             .tasks
@@ -677,7 +674,7 @@ mod tests {
             "git_branch": "main"
         });
 
-        let res = handler.execute(args, state.clone()).await.unwrap();
+        let res = handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(res.contains("Error fix logged"));
     }
 
@@ -689,7 +686,7 @@ mod tests {
         let handler = GetProjectHealthHandler;
         let args = json!({"namespace": "global"});
 
-        let res = handler.execute(args, state.clone()).await.unwrap();
+        let res = handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(res.contains("unresolved_tech_debt"));
     }
 
@@ -707,8 +704,7 @@ mod tests {
         });
         let res1 = decision_handler
             .execute(args_dec, state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res1, "Decision logged as ADR-0001");
 
         let debt_handler = LogTechDebtHandler;
@@ -724,8 +720,7 @@ mod tests {
         });
         let res2 = debt_handler
             .execute(args_debt, state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res2, "Tech debt logged");
 
         let list_debt = ListTechDebtHandler;
@@ -734,8 +729,7 @@ mod tests {
                 json!({"namespace": "global", "include_resolved": false}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res3.contains("Hardcoded path"));
 
         let pref_handler = LearnPreferenceHandler;
@@ -745,12 +739,11 @@ mod tests {
         });
         let res4 = pref_handler
             .execute(args_pref, state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res4, "Preference learned");
 
         let read_pref = ReadPreferencesHandler;
-        let res5 = read_pref.execute(json!({}), state.clone()).await.unwrap();
+        let res5 = read_pref.execute(json!({}), state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(res5.contains("use spaces"));
     }
 
@@ -768,14 +761,12 @@ mod tests {
         });
         code_handler
             .execute(args_code, state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
 
         let query_changes = QueryRecentChangesHandler;
         let res_changes = query_changes
             .execute(json!({}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res_changes.contains("main.rs"));
 
         let debt_handler = LogTechDebtHandler;
@@ -791,8 +782,7 @@ mod tests {
         });
         debt_handler
             .execute(args_debt, state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
 
         // resolve it
         let list_debt = ListTechDebtHandler;
@@ -801,16 +791,14 @@ mod tests {
                 json!({"namespace": "global", "include_resolved": false}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         let uuid_start = debt_list.find("id\":\"").unwrap() + 5;
         let uuid = &debt_list[uuid_start..uuid_start + 36];
 
         let resolve_debt = ResolveTechDebtHandler;
         resolve_debt
             .execute(json!({"id": uuid}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
     }
 
     #[tokio::test]
@@ -844,8 +832,7 @@ mod tests {
         let omni = OmniSearchHandler;
         let omni_res = omni
             .execute(json!({"query": "Omni"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         // tracing::info!("OMNI RES: {}", omni_res);
         assert!(
             omni_res.contains("omni-1"),

server/src/handlers/notes.rs

@@ -19,7 +19,7 @@ impl McpTool for AddStickyNoteHandler {
         crate::mcp::tool_def::<AddStickyNoteTool>("add_sticky_note", "Execute add_sticky_note")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: AddStickyNoteTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.sticky.modify(|notes| {
             notes.push(StickyNote {
@@ -47,10 +47,10 @@ impl McpTool for ReadStickyNotesHandler {
         )
     }
 
-    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let data = state
             .sticky
-            .read_with(|s| serde_json::to_string(s).map_err(|e| e.to_string()))?;
+            .read_with(|s| Ok::<String, crate::error::AppError>(serde_json::to_string(s)?))?;
         Ok(data)
     }
 }
@@ -70,7 +70,7 @@ impl McpTool for DeleteStickyNoteHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: DeleteStickyNoteTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut success = false;
         state.sticky.modify(|notes| {
@@ -82,7 +82,7 @@ impl McpTool for DeleteStickyNoteHandler {
         if success {
             Ok("Sticky note deleted.".to_string())
         } else {
-            Err("Invalid sticky note index.".to_string())
+            Err(crate::error::AppError::Internal("Invalid sticky note index.".to_string()))
         }
     }
 }
@@ -102,7 +102,7 @@ impl McpTool for ClearStickyNotesHandler {
         )
     }
 
-    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, _args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         state.sticky.modify(|notes| {
             notes.clear();
         });
@@ -125,7 +125,7 @@ impl McpTool for LeaveHandoffMemoHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: LeaveHandoffMemoTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.handoff_memos.modify(|memos| {
             memos.push(crate::models::HandoffMemo {
@@ -156,7 +156,7 @@ impl McpTool for ReadHandoffMemosHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ReadHandoffMemosTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.handoff_memos.read_with(|items| {
             let filtered: Vec<_> = items
@@ -169,7 +169,7 @@ impl McpTool for ReadHandoffMemosHandler {
                     }
                 })
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -190,7 +190,7 @@ impl McpTool for ClearHandoffMemosHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ClearHandoffMemosTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let ids: HashSet<_> = req.ids.into_iter().collect();
         state
@@ -215,7 +215,7 @@ impl McpTool for AddSessionSummaryHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: AddSessionSummaryTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.session_summaries.modify(|summaries| {
             summaries.push(crate::models::SessionSummary {
@@ -244,7 +244,7 @@ impl McpTool for GenerateStandupReportHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: GenerateStandupReportTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let cutoff = crate::handlers::utils::now_secs().saturating_sub(req.hours_lookback * 3600);
@@ -280,25 +280,23 @@ mod tests {
             "content": "Buy milk",
         });
 
-        let res = add_handler.execute(args, state.clone()).await.unwrap();
+        let res = add_handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(res.contains("Sticky note added"));
 
         let read_handler = ReadStickyNotesHandler;
         let res2 = read_handler
             .execute(json!({}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res2.contains("Buy milk"));
 
         let delete_handler = DeleteStickyNoteHandler;
         let args2 = json!({"index": 1});
-        let res3 = delete_handler.execute(args2, state.clone()).await.unwrap();
+        let res3 = delete_handler.execute(args2, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res3, "Sticky note deleted.");
 
         let res4 = read_handler
             .execute(json!({}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(!res4.contains("Buy milk"));
     }
 
@@ -314,14 +312,13 @@ mod tests {
             "namespace": "global"
         });
 
-        let res = handoff_handler.execute(args, state.clone()).await.unwrap();
+        let res = handoff_handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res, "Handoff memo left");
 
         let read_handoff = ReadHandoffMemosHandler;
         let res2 = read_handoff
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res2.contains("Finished implementing graph tests"));
 
         let summary_handler = AddSessionSummaryHandler;
@@ -331,8 +328,7 @@ mod tests {
         });
         let res3 = summary_handler
             .execute(args_sum, state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res3, "Session summary added");
 
         let standup_handler = GenerateStandupReportHandler;
@@ -341,8 +337,7 @@ mod tests {
                 json!({"namespace": "global", "hours_lookback": 24}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(!res4.is_empty());
     }
 }

server/src/handlers/tasks.rs

@@ -18,7 +18,7 @@ impl McpTool for AddTaskHandler {
         crate::mcp::tool_def::<AddTaskTool>("add_task", "Execute add_task")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: AddTaskTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let now = crate::handlers::utils::now_secs();
         let task_id = uuid::Uuid::new_v4().to_string();
@@ -59,7 +59,7 @@ impl McpTool for DeleteTaskHandler {
         crate::mcp::tool_def::<DeleteTaskTool>("delete_task", "Execute delete_task")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: DeleteTaskTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut deleted_count = 0;
         let mut actually_deleted = Vec::new();
@@ -114,7 +114,7 @@ impl McpTool for DeleteTaskHandler {
             ][0]
             .clone())
         } else {
-            Err("Task not found. Please use the list_active_tasks tool to verify the correct task ID.".to_string())
+            Err(crate::error::AppError::Internal("Task not found. Please use the list_active_tasks tool to verify the correct task ID.".to_string()))
         }
     }
 }
@@ -134,7 +134,7 @@ impl McpTool for UpdateTaskStatusHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: UpdateTaskStatusTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut found = false;
         let mut blocked = false;
@@ -250,14 +250,14 @@ impl McpTool for UpdateTaskStatusHandler {
         });
 
         if blocked {
-            Err(format!(
+            Err(crate::error::AppError::Internal(format!(
                 "Error: Cannot transition task. {}",
                 blocker_details
-            ))
+            )))
         } else if found {
             Ok("Task status updated.".to_string())
         } else {
-            Err("Task not found. Please use the list_active_tasks tool to verify the correct task ID.".to_string())
+            Err(crate::error::AppError::Internal("Task not found. Please use the list_active_tasks tool to verify the correct task ID.".to_string()))
         }
     }
 }
@@ -277,7 +277,7 @@ impl McpTool for ListActiveTasksHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ListActiveTasksTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.tasks.read_with(|tasks| {
             let filtered: Vec<_> = tasks
@@ -294,7 +294,7 @@ impl McpTool for ListActiveTasksHandler {
                     status_match && branch_match
                 })
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -315,7 +315,7 @@ impl McpTool for SetAcceptanceCriteriaHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: SetAcceptanceCriteriaTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut success = false;
@@ -337,7 +337,7 @@ impl McpTool for SetAcceptanceCriteriaHandler {
         if success {
             Ok("Acceptance criteria set successfully.".to_string())
         } else {
-            Err("Task not found. Please use the list_active_tasks tool to verify the correct task ID.".to_string())
+            Err(crate::error::AppError::Internal("Task not found. Please use the list_active_tasks tool to verify the correct task ID.".to_string()))
         }
     }
 }
@@ -357,7 +357,7 @@ impl McpTool for VerifyAcceptanceCriteriaHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: VerifyAcceptanceCriteriaTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut success = false;
@@ -386,7 +386,7 @@ impl McpTool for VerifyAcceptanceCriteriaHandler {
         } else if already_met {
             Ok("Acceptance criteria was already met.".to_string())
         } else {
-            Err("Acceptance criteria or task not found.".to_string())
+            Err(crate::error::AppError::Internal("Acceptance criteria or task not found.".to_string()))
         }
     }
 }
@@ -403,7 +403,7 @@ impl McpTool for AddMilestoneHandler {
         crate::mcp::tool_def::<AddMilestoneTool>("add_milestone", "Execute add_milestone")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: AddMilestoneTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.milestones.modify(|ms| {
             ms.push(crate::models::Milestone {
@@ -430,7 +430,7 @@ impl McpTool for UpdateMilestoneHandler {
         crate::mcp::tool_def::<UpdateMilestoneTool>("update_milestone", "Execute update_milestone")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: UpdateMilestoneTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut found = false;
         state.milestones.modify(|ms| {
@@ -445,10 +445,7 @@ impl McpTool for UpdateMilestoneHandler {
         if found {
             Ok("Milestone updated".to_string())
         } else {
-            Err(
+            Err(crate::error::AppError::Internal("Milestone not found. Please verify the milestone ID using list_milestones.".to_string()))
-                "Milestone not found. Please verify the milestone ID using list_milestones."
-                    .to_string(),
-            )
         }
     }
 }
@@ -465,7 +462,7 @@ impl McpTool for ListMilestonesHandler {
         crate::mcp::tool_def::<ListMilestonesTool>("list_milestones", "Execute list_milestones")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ListMilestonesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.milestones.read_with(|items| {
             let filtered: Vec<_> = items
@@ -478,7 +475,7 @@ impl McpTool for ListMilestonesHandler {
                     }
                 })
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -502,14 +499,13 @@ mod tests {
             "acceptance_criteria": ["Stop the noise", "Reach lightspeed"],
         });
 
-        let res = add_handler.execute(args, state.clone()).await.unwrap();
+        let res = add_handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(res.contains("Task added with ID:"));
 
         let list_handler = ListActiveTasksHandler;
         let res2 = list_handler
             .execute(json!({}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res2.contains("Fix the hyperdrive"));
     }
 
@@ -524,8 +520,7 @@ mod tests {
                 json!({"title": "Test", "description": "test"}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
 
         let id_start = res.find("ID: ").unwrap() + 4;
         let task_id = res[id_start..].trim();
@@ -535,14 +530,13 @@ mod tests {
             "id": task_id,
             "status": "done"
         });
-        let res3 = update_handler.execute(args, state.clone()).await.unwrap();
+        let res3 = update_handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res3, "Task status updated.");
 
         let list_handler = ListActiveTasksHandler;
         let res4 = list_handler
             .execute(json!({}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(!res4.contains(task_id));
     }
 
@@ -561,7 +555,7 @@ mod tests {
             "end_date": 1700000000,
             "namespace": "global"
         });
-        let res1 = add_milestone.execute(args_ms, state.clone()).await.unwrap();
+        let res1 = add_milestone.execute(args_ms, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(res1.contains("Milestone added"));
 
         // Fetch milestone ID from state directly to update
@@ -573,15 +567,14 @@ mod tests {
             "id": ms_id,
             "status": "completed"
         });
-        let res2 = update_ms.execute(args_ums, state.clone()).await.unwrap();
+        let res2 = update_ms.execute(args_ums, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res2, "Milestone updated");
 
         // List Milestones
         let list_ms = ListMilestonesHandler;
         let res3 = list_ms
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res3.contains("completed"));
         assert!(res3.contains("Release 1.0"));
 
@@ -592,8 +585,7 @@ mod tests {
                 json!({"title": "Test", "description": "desc"}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         let task_id = res_task[res_task.find("ID: ").unwrap() + 4..].trim();
 
         let set_ac = SetAcceptanceCriteriaHandler;
@@ -602,7 +594,7 @@ mod tests {
             "task_title": "Test",
             "criteria": ["Do X", "Do Y"]
         });
-        let res4 = set_ac.execute(args_ac, state.clone()).await.unwrap();
+        let res4 = set_ac.execute(args_ac, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res4, "Acceptance criteria set successfully.");
 
         let verify_ac = VerifyAcceptanceCriteriaHandler;
@@ -611,7 +603,7 @@ mod tests {
             "criteria": "Do X",
             "proof": "I did X"
         });
-        let res5 = verify_ac.execute(args_vac, state.clone()).await.unwrap();
+        let res5 = verify_ac.execute(args_vac, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(res5.contains("Acceptance criteria verified"));
     }
 
@@ -626,8 +618,7 @@ mod tests {
                 json!({"title": "Parent", "description": "p"}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         let parent_id = parent[parent.find("ID: ").unwrap() + 4..]
             .trim()
             .to_string();
@@ -637,15 +628,13 @@ mod tests {
                 json!({"title": "Child", "description": "c", "parent_id": parent_id}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         let _child_id = child[child.find("ID: ").unwrap() + 4..].trim().to_string();
 
         let del_task = DeleteTaskHandler;
         let res_del = del_task
             .execute(json!({"id": parent_id}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res_del.contains("Deleted task and its children (2 total)."));
     }
 }

server/src/handlers/vision.rs

@@ -24,9 +24,9 @@ impl McpTool for WriteClipboardHandler {
         )
     }
 
-    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> crate::error::Result<String> {
         let tool_args: WriteClipboardTool =
-            serde_json::from_value(args).map_err(|e| format!("Invalid args: {}", e))?;
+            serde_json::from_value(args).map_err(|e| crate::error::AppError::Internal(format!("Invalid args: {}", e)))?;
             
         tokio::task::spawn_blocking(move || {
             let mut msgs = Vec::new();
@@ -63,11 +63,11 @@ impl McpTool for WriteClipboardHandler {
                             if clipboard.set_image(img_data).is_ok() {
                                 msgs.push("Wrote image");
                             } else {
-                                return Err("Failed to write image to clipboard".to_string());
+                                return Err(crate::error::AppError::Internal("Failed to write image to clipboard".to_string()));
                             }
                         }
                     },
-                    Err(e) => return Err(format!("Failed to open image {}: {}", image_path, e)),
+                    Err(e) => return Err(crate::error::AppError::Internal(format!("Failed to open image {}: {}", image_path, e))),
                 }
             }
             
@@ -78,7 +78,7 @@ impl McpTool for WriteClipboardHandler {
             }
         })
         .await
-        .map_err(|e| format!("Task panic: {}", e))?
+        .map_err(|e| crate::error::AppError::Internal(format!("Task panic: {}", e)))?
     }
 }
 
@@ -97,8 +97,8 @@ impl McpTool for ReadClipboardHandler {
         )
     }
 
-    async fn execute(&self, _args: Value, _state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, _args: Value, _state: Arc<MemoryState>) -> crate::error::Result<String> {
-        let result = tokio::task::spawn_blocking(move || -> Result<Value, String> {
+        let result = tokio::task::spawn_blocking(move || -> crate::error::Result<serde_json::Value> {
             let mut out = serde_json::Map::new();
 
             if let Ok(_clip) = Clipboard::new_attempts(3) {
@@ -149,9 +149,9 @@ impl McpTool for ReadClipboardHandler {
             Ok(Value::Object(out))
         })
         .await
-        .map_err(|e| format!("Task panic: {}", e))??;
+        .map_err(|e| crate::error::AppError::Internal(format!("Task panic: {}", e)))??;
 
-        Ok(serde_json::to_string_pretty(&result).unwrap())
+        Ok::<String, crate::error::AppError>(serde_json::to_string_pretty(&result)?)
     }
 }
 use crate::tools::ToggleClipboardWatchModeTool;
@@ -171,7 +171,7 @@ impl McpTool for ToggleClipboardWatchModeHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let tool_args: ToggleClipboardWatchModeTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         
         let mut watch_mode = state.clipboard_watch_mode.write().await;

server/src/handlers/workspaces.rs

@@ -18,7 +18,7 @@ impl McpTool for PinFileHandler {
         crate::mcp::tool_def::<PinFileTool>("pin_file", "Execute pin_file")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: PinFileTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.pinned_files.modify(|pinned| {
             pinned.retain(|p| p.namespace != req.namespace || p.file_path != req.file_path);
@@ -45,7 +45,7 @@ impl McpTool for UnpinFileHandler {
         crate::mcp::tool_def::<UnpinFileTool>("unpin_file", "Execute unpin_file")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: UnpinFileTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.pinned_files.modify(|pinned| {
             pinned.retain(|p| p.namespace != req.namespace || p.file_path != req.file_path)
@@ -69,7 +69,7 @@ impl McpTool for ListPinnedFilesHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ListPinnedFilesTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.pinned_files.read_with(|pinned| {
             let filtered: Vec<_> = pinned
@@ -89,7 +89,7 @@ impl McpTool for ListPinnedFilesHandler {
                     ns_match && branch_match
                 })
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -107,7 +107,7 @@ impl McpTool for StoreSnippetHandler {
         crate::mcp::tool_def::<StoreSnippetTool>("store_snippet", "Execute store_snippet")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: StoreSnippetTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let req_name = req.name.clone(); // Keep for the OK message and retain closure
         let text_to_embed = format!("Name: {}\nLanguage: {}\nDescription: {}\nCode: {}", req.name, req.language, req.description, req.code);
@@ -145,7 +145,7 @@ impl McpTool for SearchSnippetsHandler {
         crate::mcp::tool_def::<SearchSnippetsTool>("search_snippets", "Execute search_snippets")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: SearchSnippetsTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let query = req.query;
         let data = state.snippets.read_with(|snippets| {
@@ -157,7 +157,7 @@ impl McpTool for SearchSnippetsHandler {
                         || contains_ignore_ascii_case(&s.language, &query)
                 })
                 .collect();
-            serde_json::to_string(&results).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&results)?)
         })?;
         Ok(data)
     }
@@ -175,7 +175,7 @@ impl McpTool for DeleteSnippetHandler {
         crate::mcp::tool_def::<DeleteSnippetTool>("delete_snippet", "Execute delete_snippet")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: DeleteSnippetTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let mut deleted = false;
         state.snippets.modify(|snippets| {
@@ -188,10 +188,7 @@ impl McpTool for DeleteSnippetHandler {
             drop(idx.delete_document(&req.name));
             Ok("Snippet deleted.".to_string())
         } else {
-            Err(
+            Err(crate::error::AppError::Internal("Snippet not found. Please verify the snippet ID using search_snippets.".to_string()))
-                "Snippet not found. Please verify the snippet ID using search_snippets."
-                    .to_string(),
-            )
         }
     }
 }
@@ -211,7 +208,7 @@ impl McpTool for SaveContextWorkspaceHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: SaveContextWorkspaceTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.context_workspaces.modify(|ws| {
@@ -243,7 +240,7 @@ impl McpTool for LoadContextWorkspaceHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: LoadContextWorkspaceTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.context_workspaces.read_with(|ws| {
@@ -272,7 +269,7 @@ impl McpTool for ListContextWorkspacesHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ListContextWorkspacesTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.context_workspaces.read_with(|ws| {
@@ -280,7 +277,7 @@ impl McpTool for ListContextWorkspacesHandler {
                 .iter()
                 .filter(|w| req.namespace.as_ref().is_none_or(|ns| &w.namespace == ns))
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -301,7 +298,7 @@ impl McpTool for DeleteContextWorkspaceHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: crate::tools::DeleteContextWorkspaceTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
 
@@ -319,7 +316,7 @@ impl McpTool for DeleteContextWorkspaceHandler {
         if found {
             Ok("Context workspace deleted successfully".to_string())
         } else {
-            Err("Context workspace not found".to_string())
+            Err(crate::error::AppError::Internal("Context workspace not found".to_string()))
         }
     }
 }
@@ -339,7 +336,7 @@ impl McpTool for AddPrChecklistItemHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: AddPrChecklistItemTool =
             serde_json::from_value(args).map_err(|e| e.to_string())?;
         state.pr_checklists.modify(|items| {
@@ -365,14 +362,14 @@ impl McpTool for GetPrChecklistHandler {
         crate::mcp::tool_def::<GetPrChecklistTool>("get_pr_checklist", "Execute get_pr_checklist")
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: GetPrChecklistTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         let data = state.pr_checklists.read_with(|items| {
             let filtered: Vec<_> = items
                 .iter()
                 .filter(|i| i.namespace == req.namespace)
                 .collect();
-            serde_json::to_string(&filtered).map_err(|e| e.to_string())
+            Ok::<String, crate::error::AppError>(serde_json::to_string(&filtered)?)
         })?;
         Ok(data)
     }
@@ -393,7 +390,7 @@ impl McpTool for ClearPrChecklistHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let req: ClearPrChecklistTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         state
             .pr_checklists
@@ -423,14 +420,13 @@ mod tests {
             "active_task_ids": ["123"]
         });
 
-        let res = save_handler.execute(args, state.clone()).await.unwrap();
+        let res = save_handler.execute(args, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res, "Context workspace saved");
 
         let list_handler = ListContextWorkspacesHandler;
         let res2 = list_handler
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res2.contains("wsl-session"));
         assert!(res2.contains("src/main.rs"));
     }
@@ -450,8 +446,7 @@ mod tests {
         });
         let res1 = store_handler
             .execute(args_snip, state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res1, "Snippet 'init_db' stored.");
 
         let search_handler = SearchSnippetsHandler;
@@ -460,8 +455,7 @@ mod tests {
                 json!({"query": "SELECT", "namespace": "global"}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         // Skip assertion since it requires index rebuild
 
         let pr_handler = AddPrChecklistItemHandler;
@@ -469,14 +463,13 @@ mod tests {
             "description": "Check coverage",
             "namespace": "global"
         });
-        let res3 = pr_handler.execute(args_pr, state.clone()).await.unwrap();
+        let res3 = pr_handler.execute(args_pr, state.clone()).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res3, "PR checklist item added");
 
         let get_pr = GetPrChecklistHandler;
         let res4 = get_pr
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res4.contains("Check coverage"));
 
         // Pin lifecycle
@@ -486,15 +479,13 @@ mod tests {
                 json!({"file_path": "src/lib.rs", "namespace": "global"}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res5, "File pinned");
 
         let list_pins = ListPinnedFilesHandler;
         let res6 = list_pins
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert!(res6.contains("src/lib.rs"));
 
         let unpin = UnpinFileHandler;
@@ -503,16 +494,14 @@ mod tests {
                 json!({"file_path": "src/lib.rs", "namespace": "global"}),
                 state.clone(),
             )
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res7, "File unpinned");
 
         // Clear PR
         let clear_pr = ClearPrChecklistHandler;
         let res8 = clear_pr
             .execute(json!({"namespace": "global"}), state.clone())
-            .await
+            .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
-            .unwrap();
         assert_eq!(res8, "PR checklist cleared");
     }
 }
@@ -534,11 +523,11 @@ impl McpTool for ReadDirectoryArchitectureHandler {
         )
     }
 
-    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, _state: Arc<MemoryState>) -> crate::error::Result<String> {
         let tool_args: ReadDirectoryArchitectureTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         
         let dir = tool_args.directory.clone();
-        let result = tokio::task::spawn_blocking(move || -> Result<String, String> {
+        let result = tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
             let mut summary = String::new();
             
             fn visit_dirs(dir: &std::path::Path, summary: &mut String, depth: usize) -> std::io::Result<()> {
@@ -581,7 +570,7 @@ impl McpTool for ReadDirectoryArchitectureHandler {
             
             let path = std::path::Path::new(&dir);
             if !path.exists() {
-                return Err(format!("Directory does not exist: {}", dir));
+                return Err(crate::error::AppError::Internal(format!("Directory does not exist: {}", dir)));
             }
             
             summary.push_str(&format!("Architecture of {}:\n", dir));
@@ -590,7 +579,7 @@ impl McpTool for ReadDirectoryArchitectureHandler {
             Ok(summary)
         })
         .await
-        .map_err(|e| format!("Task panic: {}", e))??;
+        .map_err(|e| crate::error::AppError::Internal(format!("Task panic: {}", e)))??;
 
         Ok(result)
     }
@@ -613,7 +602,7 @@ impl McpTool for SemanticCodeSearchHandler {
         )
     }
 
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let tool_args: SemanticCodeSearchTool = serde_json::from_value(args).map_err(|e| e.to_string())?;
         
         let query_emb = generate_embedding_async(tool_args.query.clone()).await?;

server/src/router.rs

@@ -12,7 +12,7 @@ pub trait McpTool: Send + Sync {
     fn schema(&self) -> Value;
 
     /// Execute the tool with the given arguments
-    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> Result<String, String>;
+    async fn execute(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<String>;
 }
 
 #[async_trait]
@@ -25,7 +25,7 @@ pub trait McpResource: Send + Sync {
     fn mime_type(&self) -> Option<&'static str> {
         Some("application/json")
     }
-    async fn read(&self, state: Arc<MemoryState>) -> Result<String, String>;
+    async fn read(&self, state: Arc<MemoryState>) -> crate::error::Result<String>;
 }
 
 #[async_trait]
@@ -37,7 +37,7 @@ pub trait McpPrompt: Send + Sync {
     fn arguments(&self) -> serde_json::Value {
         serde_json::json!([])
     }
-    async fn get(&self, args: Value, state: Arc<MemoryState>) -> Result<serde_json::Value, String>;
+    async fn get(&self, args: Value, state: Arc<MemoryState>) -> crate::error::Result<serde_json::Value>;
 }
 
 struct GraphEntitiesResource;
@@ -52,15 +52,14 @@ impl McpResource for GraphEntitiesResource {
     fn description(&self) -> Option<&'static str> {
         Some("All nodes and entities currently stored in the knowledge graph")
     }
-    async fn read(&self, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn read(&self, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let state_clone = Arc::clone(&state);
-        tokio::task::spawn_blocking(move || {
+        tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
             let graph = state_clone.graph.cache.read().unwrap();
             let data: Vec<_> = graph.entities.values().collect();
-            serde_json::to_string_pretty(&data).map_err(|e| e.to_string())
+            Ok(serde_json::to_string_pretty(&data)?)
         })
-        .await
+        .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?
-        .unwrap()
     }
 }
 
@@ -76,15 +75,14 @@ impl McpResource for GraphRelationsResource {
     fn description(&self) -> Option<&'static str> {
         Some("All relationships between entities currently stored in the knowledge graph")
     }
-    async fn read(&self, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn read(&self, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let state_clone = Arc::clone(&state);
-        tokio::task::spawn_blocking(move || {
+        tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
             let graph = state_clone.graph.cache.read().unwrap();
             let data = &graph.relations;
-            serde_json::to_string_pretty(&data).map_err(|e| e.to_string())
+            Ok(serde_json::to_string_pretty(&data)?)
         })
-        .await
+        .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?
-        .unwrap()
     }
 }
 
@@ -100,18 +98,17 @@ impl McpResource for TasksActiveResource {
     fn description(&self) -> Option<&'static str> {
         Some("List of currently active tasks")
     }
-    async fn read(&self, state: Arc<MemoryState>) -> Result<String, String> {
+    async fn read(&self, state: Arc<MemoryState>) -> crate::error::Result<String> {
         let state_clone = Arc::clone(&state);
-        tokio::task::spawn_blocking(move || {
+        tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
             let tasks = state_clone.tasks.cache.read().unwrap();
             let data: Vec<_> = tasks
                 .iter()
                 .filter(|t| t.status != "completed" && t.status != "done")
                 .collect();
-            serde_json::to_string_pretty(&data).map_err(|e| e.to_string())
+            Ok(serde_json::to_string_pretty(&data)?)
         })
-        .await
+        .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?
-        .unwrap()
     }
 }
 
@@ -128,7 +125,7 @@ impl McpPrompt for AnalyzeTechDebtPrompt {
         &self,
         _args: Value,
         _state: Arc<MemoryState>,
-    ) -> Result<serde_json::Value, String> {
+    ) -> crate::error::Result<serde_json::Value> {
         Ok(serde_json::json!({
             "messages": [
                 {
@@ -190,14 +187,13 @@ impl MemoryHandler {
             fn description(&self) -> Option<&'static str> {
                 Some("Recent terminal execution history and exit codes")
             }
-            async fn read(&self, state: Arc<MemoryState>) -> Result<String, String> {
+            async fn read(&self, state: Arc<MemoryState>) -> crate::error::Result<String> {
                 let state_clone = Arc::clone(&state);
-                tokio::task::spawn_blocking(move || {
+                tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
                     let items = state_clone.terminal_history.cache.read().unwrap();
-                    serde_json::to_string_pretty(&*items).map_err(|e| e.to_string())
+                    Ok(serde_json::to_string_pretty(&*items)?)
                 })
-                .await
+                .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?
-                .unwrap()
             }
         }
         struct PinnedFilesResource;
@@ -212,14 +208,13 @@ impl MemoryHandler {
             fn description(&self) -> Option<&'static str> {
                 Some("Currently pinned files in the workspace")
             }
-            async fn read(&self, state: Arc<MemoryState>) -> Result<String, String> {
+            async fn read(&self, state: Arc<MemoryState>) -> crate::error::Result<String> {
                 let state_clone = Arc::clone(&state);
-                tokio::task::spawn_blocking(move || {
+                tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
                     let items = state_clone.pinned_files.cache.read().unwrap();
-                    serde_json::to_string_pretty(&*items).map_err(|e| e.to_string())
+                    Ok(serde_json::to_string_pretty(&*items)?)
                 })
-                .await
+                .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?
-                .unwrap()
             }
         }
 
@@ -235,14 +230,13 @@ impl MemoryHandler {
             fn description(&self) -> Option<&'static str> {
                 Some("Project milestones and their status")
             }
-            async fn read(&self, state: Arc<MemoryState>) -> Result<String, String> {
+            async fn read(&self, state: Arc<MemoryState>) -> crate::error::Result<String> {
                 let state_clone = Arc::clone(&state);
-                tokio::task::spawn_blocking(move || {
+                tokio::task::spawn_blocking(move || -> crate::error::Result<String> {
                     let items = state_clone.milestones.cache.read().unwrap();
-                    serde_json::to_string_pretty(&*items).map_err(|e| e.to_string())
+                    Ok(serde_json::to_string_pretty(&*items)?)
                 })
-                .await
+                .await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?
-                .unwrap()
             }
         }
 
@@ -259,7 +253,7 @@ impl MemoryHandler {
                 &self,
                 _args: Value,
                 _state: Arc<MemoryState>,
-            ) -> Result<serde_json::Value, String> {
+            ) -> crate::error::Result<serde_json::Value> {
                 Ok(serde_json::json!({
                     "messages": [
                         {
@@ -290,7 +284,7 @@ impl MemoryHandler {
                 &self,
                 _args: Value,
                 _state: Arc<MemoryState>,
-            ) -> Result<serde_json::Value, String> {
+            ) -> crate::error::Result<serde_json::Value> {
                 Ok(serde_json::json!({"
                     messages": [
                         {
@@ -506,7 +500,7 @@ impl MemoryHandler {
                             });
                             Some(crate::mcp::success(id, payload))
                         }
-                        Err(e) => Some(crate::mcp::error(id, -32603, &e)),
+                        Err(e) => Some(crate::mcp::error(id, -32603, &e.to_string())),
                     }
                 } else {
                     Some(crate::mcp::error(id, -32602, "Resource not found"))
@@ -544,7 +538,7 @@ impl MemoryHandler {
                 if let Some(prompt) = self.prompts.get(name) {
                     match prompt.get(args, Arc::clone(&self.state)).await {
                         Ok(messages) => Some(crate::mcp::success(id, messages)),
-                        Err(e) => Some(crate::mcp::error(id, -32603, &e)),
+                        Err(e) => Some(crate::mcp::error(id, -32603, &e.to_string())),
                     }
                 } else {
                     Some(crate::mcp::error(id, -32602, "Prompt not found"))
@@ -562,10 +556,10 @@ impl MemoryHandler {
                 self.state
                     .broadcast_activity(&format!("Agent executed tool: {}", name));
 
-                let result: Result<String, String> = if let Some(tool) = self.tools.get(name) {
+                let result: crate::error::Result<String> = if let Some(tool) = self.tools.get(name) {
                     tool.execute(args, self.state.clone()).await
                 } else {
-                    Err(format!("Unknown tool: {}", name))
+                    Err(crate::error::AppError::Internal(format!("Unknown tool: {}", name)))
                 };
 
                 match result {
@@ -579,7 +573,7 @@ impl MemoryHandler {
                     Err(e) => {
                         tracing::error!("Tool {} failed: {}", name, e);
                         let payload = serde_json::json!({
-                            "content": [{"type": "text", "text": e}],
+                            "content": [{"type": "text", "text": e.to_string()}],
                             "isError": true
                         });
                         Some(crate::mcp::success(id_clone, payload))
@@ -627,7 +621,7 @@ mod tests {
             "params": {}
         });
 
-        let res_list = handler.handle_request(list_tools_req).await.unwrap();
+        let res_list = handler.handle_request(list_tools_req).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res_list["jsonrpc"], "2.0");
         assert_eq!(res_list["id"], 1);
         assert!(res_list["result"]["tools"].as_array().unwrap().len() > 10);
@@ -646,7 +640,7 @@ mod tests {
             "method": "resources/list",
             "params": {}
         });
-        let res_list = handler.handle_request(req_list_res).await.unwrap();
+        let res_list = handler.handle_request(req_list_res).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         let resources_arr = res_list["result"]["resources"].as_array().unwrap();
         assert!(
             resources_arr
@@ -668,7 +662,7 @@ mod tests {
                 "uri": "memory://tasks/active"
             }
         });
-        let res_read = handler.handle_request(req_read_res).await.unwrap();
+        let res_read = handler.handle_request(req_read_res).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(
             res_read["result"]["contents"][0]["uri"],
             "memory://tasks/active"
@@ -687,7 +681,7 @@ mod tests {
             "method": "prompts/list",
             "params": {}
         });
-        let res_prompts = handler.handle_request(req_list_prompts).await.unwrap();
+        let res_prompts = handler.handle_request(req_list_prompts).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         let prompts_arr = res_prompts["result"]["prompts"].as_array().unwrap();
         assert!(prompts_arr.iter().any(|p| p["name"] == "handoff_routine"));
 
@@ -701,7 +695,7 @@ mod tests {
                 "arguments": {}
             }
         });
-        let res_get = handler.handle_request(req_get_prompt).await.unwrap();
+        let res_get = handler.handle_request(req_get_prompt).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         let messages = res_get["result"]["messages"].as_array().unwrap();
         assert_eq!(messages[0]["role"], "user");
         assert!(
@@ -728,7 +722,7 @@ mod tests {
                 "arguments": {}
             }
         });
-        let res_success = handler.handle_request(req_success).await.unwrap();
+        let res_success = handler.handle_request(req_success).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res_success["jsonrpc"], "2.0");
         assert_eq!(res_success["id"], 2);
         // A successful tool call should return a result with isError: false
@@ -748,7 +742,7 @@ mod tests {
                 }
             }
         });
-        let res_fail = handler.handle_request(req_fail).await.unwrap();
+        let res_fail = handler.handle_request(req_fail).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert_eq!(res_fail["jsonrpc"], "2.0");
         assert_eq!(res_fail["id"], 3);
         // Semantic failures must explicitly return isError: true inside the result to halt the LLM
@@ -766,7 +760,7 @@ mod tests {
             "id": 4,
             "method": "unknown_method_xyz"
         });
-        let res_unknown = handler.handle_request(req_unknown).await.unwrap();
+        let res_unknown = handler.handle_request(req_unknown).await.map_err(|e| crate::error::AppError::Internal(e.to_string()))?;
         assert!(res_unknown.get("error").is_some());
         assert_eq!(res_unknown["error"]["code"], -32601);
     }