peta-mcp-runner

peta-mcp-runner is a generic execution image used by peta-core in Docker deployments for CustomStdio servers.

Purpose

When peta-core runs inside Docker and a CustomStdio server command is not docker, peta-core runs the command in this image:

docker run -i --rm --init ... petaio/mcp-runner:latest <command> <args...>

This keeps the main peta-core container isolated from arbitrary runtime dependencies.

Built-in tooling

• Node.js LTS (includes npm and npx)
• Python 3 + pip
• uv / uvx
• bash / sh
• git, curl, ca-certificates, tini

Cache behavior

peta-core mounts a shared cache volume into /home/runner/.cache for package/runtime caches.

Related environment defaults in this image:

• npm_config_cache=/home/runner/.cache/npm
• UV_CACHE_DIR=/home/runner/.cache/uv
• PIP_CACHE_DIR=/home/runner/.cache/pip

Scope and non-goals

• This image does not include business-specific MCP logic.
• This image does not auto-mount host source directories.
• Commands that require host local project files must provide explicit mounts outside of this image contract.

Build and publish

./docker-build-push.sh

Optional environment variables:

• IMAGE_NAME (default: petaio/mcp-runner)
• TAG (default: latest)
• PLATFORMS (default: linux/amd64,linux/arm64)