From 167a52ca5da211171548cd82f851c377999488e5 Mon Sep 17 00:00:00 2001
From: wwhsaber <wwhsaber@foxmail.com>
Date: Sun, 31 May 2026 21:05:53 +0800
Subject: [PATCH] fix: handle missing/empty task param gracefully in
 codegraph_context

Two changes to address #577:

1. In handleContext, fall back from  to  so MCP
   clients that pass  instead of  still work.

2. In validateString, improve error messages:
   - Show the actual type/value received instead of generic message
   - Add hint about passing the parameter directly (not wrapped)
   - Trim whitespace before checking length
   - Distinguish between undefined/non-string vs whitespace-only

The root cause is that some MCP clients (notably Cursor Agent) may pass
the search text under a different parameter name or in a malformed way.
The fallback + better diagnostics should catch these edge cases.

Fixes #577
---
 package-lock.json |  1 -
 src/mcp/tools.ts  | 23 +++++++++++++++++------
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index e418a36e5..9809977a7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1460,7 +1460,6 @@
       "integrity": "sha512-o5a9xKjbtuhY6Bi5S3+HvbRERmouabWbyUcpXXUA1u+GNUKoROi9byOJ8M0nHbHYHkYICiMlqxkg1KkYmm25Sw==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "esbuild": "^0.21.3",
         "postcss": "^8.4.43",
diff --git a/src/mcp/tools.ts b/src/mcp/tools.ts
index 2e9c6f816..8bb6e524f 100644
--- a/src/mcp/tools.ts
+++ b/src/mcp/tools.ts
@@ -873,15 +873,26 @@ export class ToolHandler {
     name: string,
     maxLength: number = MAX_INPUT_LENGTH
   ): string | ToolResult {
-    if (typeof value !== 'string' || value.length === 0) {
-      return this.errorResult(`${name} must be a non-empty string`);
+    // Accept common MCP-client aliases: if `task` is missing but `query`
+    // was supplied (or vice-versa), the caller already resolves the
+    // fallback via `args.task ?? args.query`. Here we only validate.
+    if (typeof value !== 'string') {
+      const got = value === undefined ? 'undefined' : typeof value;
+      return this.errorResult(
+        `${name} must be a non-empty string (got ${got}). ` +
+        `Make sure to pass the \`${name}\` parameter directly — not wrapped in an object or nested.`
+      );
     }
-    if (value.length > maxLength) {
+    const trimmed = value.trim();
+    if (trimmed.length === 0) {
+      return this.errorResult(`${name} must be a non-empty string (received whitespace only)`);
+    }
+    if (trimmed.length > maxLength) {
       return this.errorResult(
-        `${name} exceeds maximum length of ${maxLength} characters (got ${value.length})`
+        `${name} exceeds maximum length of ${maxLength} characters (got ${trimmed.length})`
       );
     }
-    return value;
+    return trimmed;
   }
 
   /**
@@ -1147,7 +1158,7 @@ export class ToolHandler {
    * Handle codegraph_context
    */
   private async handleContext(args: Record<string, unknown>): Promise<ToolResult> {
-    const task = this.validateString(args.task, 'task');
+    const task = this.validateString(args.task ?? args.query, 'task');
     if (typeof task !== 'string') return task;
 
     // Mark session as consulted (enables Grep/Glob/Bash)