fix(mcp): optimize get_task response payload by removing allTasks data

- Add custom processTaskResponse function to get-task.js to filter response data
- Significantly reduce MCP response size by returning only the requested task
- Preserve allTasks in CLI/UI for dependency status formatting
- Update changeset with documentation of optimization

This change maintains backward compatibility while making MCP responses
more efficient, addressing potential context overflow issues in AI clients.

.changeset/two-bats-smoke.md

@@ -8,6 +8,11 @@
   - Rename `list-tasks` to `get-tasks` for more intuitive client requests like "get my tasks"
   - Rename `show-task` to `get-task` for consistency with GET-based API naming conventions
 
+- **Optimize MCP response payloads:**
+  - Add custom `processTaskResponse` function to `get-task` MCP tool to filter out unnecessary `allTasks` array data
+  - Significantly reduce response size by returning only the specific requested task instead of all tasks
+  - Preserve dependency status relationships for the UI/CLI while keeping MCP responses lean and efficient
+
 - **Refactor project root handling for MCP Server:**
   - **Prioritize Session Roots**: MCP tools now extract the project root path directly from `session.roots[0].uri` provided by the client (e.g., Cursor).
   - **New Utility `getProjectRootFromSession`**: Added to `mcp-server/src/tools/utils.js` to encapsulate session root extraction and decoding. **Further refined for more reliable detection, especially in integrated environments, including deriving root from script path and avoiding fallback to '/'.**

mcp-server/src/tools/get-task.js

@@ -11,6 +11,24 @@ import {
 } from "./utils.js";
 import { showTaskDirect } from "../core/task-master-core.js";
 
+/**
+ * Custom processor function that removes allTasks from the response
+ * @param {Object} data - The data returned from showTaskDirect
+ * @returns {Object} - The processed data with allTasks removed
+ */
+function processTaskResponse(data) {
+  if (!data) return data;
+  
+  // If we have the expected structure with task and allTasks
+  if (data.task) {
+    // Return only the task object, removing the allTasks array
+    return data.task;
+  }
+  
+  // If structure is unexpected, return as is
+  return data;
+}
+
 /**
  * Register the get-task tool with the MCP server
  * @param {Object} server - FastMCP server instance
@@ -63,7 +81,8 @@ export function registerShowTaskTool(server) {
           log.error(`Failed to get task: ${result.error.message}`);
         }
         
-        return handleApiResult(result, log, 'Error retrieving task details');
+        // Use our custom processor function to remove allTasks from the response
+        return handleApiResult(result, log, 'Error retrieving task details', processTaskResponse);
       } catch (error) {
         log.error(`Error in get-task tool: ${error.message}\n${error.stack}`); // Add stack trace
         return createErrorResponse(`Failed to get task: ${error.message}`);