mcp-stub-to-ground-truth

Replace stubbed MCP control_request flows with ground-truth implementations from extension.js and cli.js.

2|Updated Jan 30, 2026
One-click install
npx skills add https://github.com/tankygranny05/agent-box --skill mcp-stub-to-ground-truth
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: mcp-stub-to-ground-truth
Source: https://github.com/tankygranny05/agent-box/tree/main/agent-box/seed/codex-skills/mcp-stub-to-ground-truth
Command: npx skills add https://github.com/tankygranny05/agent-box --skill mcp-stub-to-ground-truth

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

This Skill provides a structured approach to resolving issues with the MCP (Multi-Channel Protocol) in the agent's UI, specifically when control requests are stubbed or broken, leading to UI malfunctions or incorrect behavior.

Core Features & Use Cases

  • Stub Replacement: Replaces placeholder or incorrect MCP request/response handling with ground-truth implementations based on extension.js and cli.js.
  • UI Debugging: Diagnoses and fixes common MCP-related UI problems such as empty server lists, stuck spinners, or unresponsiveness.
  • Use Case: If the MCP server list in the agent's UI is consistently empty, this Skill can be used to trace the control_request flow, identify where the mcp_status is being stubbed or dropped, and implement the correct logic to fetch and display the server list.

Quick Start

Use the mcp-stub-to-ground-truth skill to debug an empty MCP server list in the UI.

Frequently Asked Questions about mcp-stub-to-ground-truth

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
Why does my MCP server list appear empty in the UI?

An empty MCP server list usually occurs when the control_request flow is stubbed or broken, causing mcp_status to drop. Tracing the request/response schema in extension.js and cli.js helps identify where the stubbing happens so you can implement the correct fetch logic.

How do I fix stuck spinners and missing tool outputs in MCP UI?

Fixing stuck spinners and missing tool outputs requires replacing stubbed MCP control_request handlers with ground-truth implementations. This enforces bidirectional control planes and channel/session correctness, validated by checking log files for dropped requests.

How do I replace stubbed MCP control requests with ground-truth implementations?

To replace stubbed MCP control requests, analyze the request/response schemas, identify placeholder logic, and implement bidirectional control planes aligned to extension.js and cli.js. Validate the new ground-truth logic using log files to ensure channel and session correctness.

What causes stubbed MCP control_request flows to break UI behavior?

Stubbed MCP control_request flows break UI behavior when placeholder logic fails to enforce channel and session correctness. Without ground-truth implementations aligned to extension.js and cli.js, the UI cannot fetch server lists or display tool outputs properly.

Do I need log files to debug MCP control request issues?

Yes, log files are required to validate MCP control request fixes and ensure channel/session correctness. They provide the trace data needed to confirm that bidirectional control planes and ground-truth implementations are functioning as intended.