Format massive JSON arrays into Markdown natively to avoid context blowouts

server/src/handlers/ast.rs

@@ -498,15 +498,37 @@ impl McpTool for FindSymbolReferencesHandler {
 
         if matches.len() < limit {
             let remaining = limit - matches.len();
+            let target_sym_clone = target_sym.clone();
             let disk_matches = tokio::task::spawn_blocking(move || {
-                scan_workspace_for_symbol(&target_sym, remaining, false, custom_dir)
+                scan_workspace_for_symbol(&target_sym_clone, remaining, false, custom_dir)
             })
             .await
             .unwrap_or_default();
             matches.extend(disk_matches);
         }
 
-        Ok(serde_yaml::to_string(&matches)?)
+        let mut out = String::new();
+        out.push_str(&format!("## Symbol References for `{}`\n\n", target_sym));
+        for match_item in &matches {
+            if let Some(source) = match_item.get("source").and_then(|s| s.as_str()) {
+                if source == "snippet" {
+                    let name = match_item.get("name").and_then(|n| n.as_str()).unwrap_or("Unknown");
+                    let code = match_item.get("code").and_then(|c| c.as_str()).unwrap_or("");
+                    out.push_str(&format!("### Snippet: {}\n```rust\n{}\n```\n\n", name, code));
+                }
+            } else {
+                let file = match_item.get("file_path").and_then(|f| f.as_str()).unwrap_or("Unknown");
+                let line = match_item.get("line").and_then(|l| l.as_u64()).unwrap_or(0);
+                let content = match_item.get("content").and_then(|c| c.as_str()).unwrap_or("");
+                out.push_str(&format!("- `{}:{}`: `{}`\n", file, line, content));
+            }
+        }
+
+        if matches.is_empty() {
+            out.push_str("No references found.\n");
+        }
+
+        Ok(out)
     }
 }
 
@@ -554,15 +576,37 @@ impl McpTool for GetCallersHandler {
 
         if callers.len() < limit {
             let remaining = limit - callers.len();
+            let target_fn_clone = target_fn.clone();
             let disk_callers = tokio::task::spawn_blocking(move || {
-                scan_workspace_for_symbol(&target_fn, remaining, true, custom_dir)
+                scan_workspace_for_symbol(&target_fn_clone, remaining, true, custom_dir)
             })
             .await
             .unwrap_or_default();
             callers.extend(disk_callers);
         }
 
-        Ok(serde_yaml::to_string(&callers)?)
+        let mut out = String::new();
+        out.push_str(&format!("## Callers for `{}`\n\n", target_fn));
+        for caller in &callers {
+            if let Some(source) = caller.get("source").and_then(|s| s.as_str()) {
+                if source == "snippet" {
+                    let name = caller.get("name").and_then(|n| n.as_str()).unwrap_or("Unknown");
+                    let code = caller.get("code").and_then(|c| c.as_str()).unwrap_or("");
+                    out.push_str(&format!("### Snippet: {}\n```rust\n{}\n```\n\n", name, code));
+                }
+            } else {
+                let file = caller.get("file_path").and_then(|f| f.as_str()).unwrap_or("Unknown");
+                let line = caller.get("line").and_then(|l| l.as_u64()).unwrap_or(0);
+                let content = caller.get("content").and_then(|c| c.as_str()).unwrap_or("");
+                out.push_str(&format!("- `{}:{}`: `{}`\n", file, line, content));
+            }
+        }
+        
+        if callers.is_empty() {
+            out.push_str("No callers found.\n");
+        }
+
+        Ok(out)
     }
 }
 
@@ -637,21 +681,35 @@ impl McpTool for AnalyzeImpactHandler {
             "LOW"
         };
 
-        let result = serde_json::json!({
-            "target_symbol": sym,
-            "risk_level": risk_level,
-            "ast_callers_count": caller_count,
-            "ast_callers_sample": callers.into_iter().take(10).collect::<Vec<_>>(),
-            "graph_relations_count": graph_count,
-            "graph_relations": kg_connected,
-            "recommendation": match risk_level {
-                "CRITICAL" | "HIGH" => "Requires comprehensive unit test verification and backwards compatibility checks before modifying.",
-                "MEDIUM" => "Verify direct call sites and run affected module tests.",
-                _ => "Safe to modify with standard unit test verification.",
-            }
-        });
+        let mut out = String::new();
+        out.push_str(&format!("## Impact Analysis for `{}`\n\n", sym));
+        out.push_str(&format!("**Risk Level:** {}\n\n", risk_level));
+        
+        let rec = match risk_level {
+            "CRITICAL" | "HIGH" => "Requires comprehensive unit test verification and backwards compatibility checks before modifying.",
+            "MEDIUM" => "Verify direct call sites and run affected module tests.",
+            _ => "Safe to modify with standard unit test verification.",
+        };
+        out.push_str(&format!("**Recommendation:** {}\n\n", rec));
+        
+        out.push_str(&format!("### AST Callers ({} total, showing up to 10)\n", caller_count));
+        for c in callers.into_iter().take(10) {
+            out.push_str(&format!("- `{}`\n", c));
+        }
+        if caller_count == 0 {
+            out.push_str("No callers found.\n");
+        }
+        out.push_str("\n");
+        
+        out.push_str(&format!("### Graph Relations ({})\n", graph_count));
+        for g in kg_connected {
+            out.push_str(&format!("- {}\n", g));
+        }
+        if graph_count == 0 {
+            out.push_str("No graph relations found.\n");
+        }
 
-        Ok(serde_yaml::to_string(&result)?)
+        Ok(out)
     }
 }