Ceedling MCP Server

An MCP (Model Context Protocol) server that bridges LLMs to the Ceedling C unit testing framework. Designed for zero-setup execution via uvx.

Features

Intelligent output filtering — Successes are summarized compactly; failures are extracted with precise file, line number, and assertion error messages.

Related MCP server: MCP Refactoring

Prerequisites

• Python ≥ 3.10

• Ceedling installed and on PATH (gem install ceedling)

• uv (for uvx execution): https://docs.astral.sh/uv/

Project Structure

ceedling-mcp-server/
├── pyproject.toml
├── README.md
└── src/
    ├── __init__.py
    ├── server.py       # FastMCP server + tool definitions
    └── parser.py        # Intelligent output parser

Quick Start

Run directly with uvx (no install needed)

From the project root:

uvx --from . ceedling-mcp

Or if published to PyPI:

uvx ceedling_mcp

Install locally for development

uv venv
uv pip install .
ceedling-mcp

Note: Editable installs (-e) are not supported with the src/ → ceedling_mcp source remapping. Use uv pip install . instead.

Use with the MCP Inspector

npx -y @modelcontextprotocol/inspector uvx --from . ceedling-mcp

Client Configuration

Gemini CLI / Claude Desktop

Add to your MCP config:

{
  "mcpServers": {
    "ceedling": {
      "command": "uvx",
      "args": ["--from", "/absolute/path/to/ceedling-mcp-server", "ceedling-mcp"]
    }
  }
}

Output Examples

All tests pass

✅ All 12 tests passed.

Failures detected

❌ 2 of 12 tests FAILED (10 passed, 0 ignored)

--- Failure Details ---
  FAIL test/test_Foo.c:42 — test_Foo_should_ReturnOne
        Expected 1 Was 0
  FAIL test/test_Bar.c:18 — test_Bar_should_Initialize
        Expected TRUE Was FALSE

Build error

🔴 BUILD ERRORS — tests did not execute
src/Foo.c:10: use of undeclared identifier 'x'

License

MIT