MCP for Pharo

MCP is an in-image Model Context Protocol
server for Pharo. It lets MCP clients inspect and change the running image
through Pharo-aware tools for packages, classes, methods, tests, repositories,
change history, debugging, and UI inspection.

MCP works through the Pharo ecosystem—compilation, refactorings, Renraku,
SUnit, Iceberg, Metacello, Epicea, and Spec—rather than patching exported Tonel
files as plain text.

Supported Versions

Pharo 12, 13, and 14 are supported. Development targets Pharo 13 while CI
checks the full matrix.

Install And Start

Load MCP in a supported image:

Metacello new
   baseline: 'MCP';
   repository: 'github://Evref-BL/MCP:main/src';
   load.

Start the Streamable HTTP server:

mcp := MCP new.
mcp port: 4000.
mcp start.

Connect a local MCP client to http://127.0.0.1:4000. Client configuration
formats differ; see Getting started for setup,
first calls, and the copyable Codex template.

Documentation

Agent Template

Copy the supplied MCP configuration, agent guide, and workflow skills into a
Pharo project:

cp -R templates/. /path/to/your/project/

Update .codex/config.toml when the image uses a port other than 4000.

Contributing

Use Pharo 13 for normal development and preserve Pharo 12/14 compatibility.
Live behavior must be verified in an image; source inspection alone is not
enough. Start with AGENTS.md and
MCP verification.