pi-codegraph

CodeGraph tools for pi

Install · Usage · How it works

Ask pi structural questions about your codebase without falling back to slow grep/read loops.

An extension for pi that gives the agent access to CodeGraph tools. CodeGraph indexes your project with tree-sitter, then pi can query symbols, callers, callees, dependency impact, files, and call paths through native extension tools.

Quick start

npm install -g @colbymchenry/codegraph
cd /path/to/project
codegraph init -i
pi install npm:@vndv/[email protected]
pi

Then ask:

Use CodeGraph. Show project structure and main entry points.

What's included

Extension tools only. There is no MCP setup for pi users to maintain.

| Tool | Description | | --- | --- | | codegraph_context | Broad task context: entry points, related symbols, callers, callees, and key code | | codegraph_search | Symbol search by name | | codegraph_node | One symbol's signature, location, source, callers, and callees | | codegraph_files | Indexed file tree | | codegraph_callers | Functions or methods that call a symbol | | codegraph_callees | Functions or methods called by a symbol | | codegraph_trace | Static call path from one symbol to another | | codegraph_impact | Impact radius for changing a symbol | | codegraph_explore | Source for several related symbols grouped by file | | codegraph_status | Index health and pending sync status |

Install

From npm:

pi install npm:@vndv/[email protected]

From GitHub:

pi install https://github.com/vndv/pi-codegraph

Local development install:

git clone https://github.com/vndv/pi-codegraph.git
cd pi-codegraph
pi install "$(pwd)"

Then /reload in pi, or restart pi.

Verify pi sees the package:

pi list

Requirements

Node.js 22.19.0 or newer is required.

CodeGraph must be installed and available on PATH:

npm install -g @colbymchenry/codegraph

This extension is tested against the @colbymchenry/codegraph npm package declared in devDependencies. Dependabot watches that package and opens update PRs when CodeGraph releases a new version.

Each project must be indexed before pi can query it:

cd /path/to/project
codegraph init -i

This package declares @earendil-works/pi-coding-agent and typebox as peer dependencies because pi provides the extension runtime.

Usage

1. Start pi inside an indexed project

cd /path/to/project
pi

2. Ask structural questions

Good prompts:

Use CodeGraph. Explain how authentication reaches the request handler.
Use CodeGraph. What calls PlanBoostSession?
Use CodeGraph. What would break if I change UserRepository?
Use CodeGraph. Show files under internal/services and important symbols.

3. Prefer the right tool

Use codegraph_context for broad "how does this work?" questions.

Use codegraph_node when you already know the symbol name.

Use codegraph_trace for "how does X reach Y?" flow questions.

Use codegraph_search for declarations and symbols, not arbitrary text or constant values.

How it works

pi extensions are not MCP configuration files. This package registers native pi tools, and each tool proxies one request to CodeGraph's MCP server internally:

codegraph serve --mcp --path <project>

The flow is:

pi agent
  -> pi-codegraph extension tool
  -> local CodeGraph MCP process
  -> .codegraph/codegraph.db in the current project
  -> structured result back to pi

That means another developer only needs the npm package, the codegraph CLI, and an initialized .codegraph index in their project. They do not need to edit pi MCP config.

Uninstall

Remove the package using the same source shown by pi list:

pi remove npm:@vndv/[email protected]

If you installed from GitHub or a local path, remove that exact entry instead:

pi remove https://github.com/vndv/pi-codegraph
pi remove /path/to/pi-codegraph

Then /reload in pi, or restart pi.

Troubleshooting

codegraph_* tools are missing

Check that pi installed the package:

pi list

Then reload or restart pi.

CodeGraph says the project is not initialized

Run:

cd /path/to/project
codegraph init -i

Node.js version is unsupported

Use Node.js 22.19.0 or newer:

nvm install 22
nvm use 22

Development

npm ci
npm run ci

npm run ci type-checks the extension, runs tests, verifies the pinned CodeGraph CLI can start, and dry-runs the npm package.

Install the local checkout into pi:

pi install /Users/vndv/Documents/programming/open-source/pi-codegraph

Before opening a pull request:

npm run ci

Release

The package is published to npm as @vndv/pi-codegraph.

Releases are automated with Changesets. Any package update, including README changes shipped to npm, needs a changeset so the release workflow can bump the version and deploy a new npm package.

For every user-facing change, add a changeset in the feature branch:

npx changeset

Choose the bump type:

• patch for fixes and docs that affect package users
• minor for new tools or behavior
• major for breaking changes

After the PR is merged to main, the release workflow opens or updates a chore: version packages pull request. That PR contains the version bump and changelog update.

Merge the version PR to publish to npm automatically.

The workflow runs:

npm run version-packages
npm run publish-packages

publish-packages runs npm publish --access public --provenance.

The workflow uses npm trusted publishing through GitHub Actions OIDC.

Local release commands are still available when needed:

npm run ci
npm run local-release

GitHub Actions needs npm trusted publishing configured for .github/workflows/publish.yml.

License

MIT