github-librarian

GitHub Librarian

Researches GitHub repos via the gh CLI and returns concise, path-first findings with line-ranged evidence.

What it does

When the answer to a question likely lives in one or more GitHub repos and you don't want exploratory gh search, tree probes, and file reads polluting your main session, github-librarian takes that work elsewhere — to an isolated subagent when one's available — and reports back with concise path-first findings. It:

• Runs targeted gh search code, tree, and contents API calls in a fresh /tmp workspace
• Caches only the files needed to prove an answer
• Cites code locations as path:lineStart-lineEnd from real file content (never from search snippets alone)
• Returns a compact Markdown report with Summary, Locations, Evidence, and Searched sections
• Aims for ≤10 tool calls per investigation

Installation

Three install paths exist. They are not equivalent — pick based on your harness.

As a Claude Code plugin (real subagent isolation)

If you're on Claude Code, install via the marketplace. This wires up the github-librarian agent and /github-librarian slash command, and uses Claude Code's built-in Task subagent so the investigation runs in a separate context — gh responses, cached files, and tree dumps stay out of your main conversation.

/plugin marketplace add diegopetrucci/ai-agents-skills
/plugin install github-librarian@diegopetrucci-claude-plugins

As a Codex plugin

If you're on Codex, add the marketplace and then install the plugin from the Codex plugin directory.

codex plugin marketplace add diegopetrucci/ai-agents-skills

Restart Codex, then install github-librarian from the "Diego Petrucci Agent Skills" marketplace in the plugin directory.

As a skill via npx skills

For all other harnesses, use npx:

npx skills add https://github.com/diegopetrucci/github-librarian --skill github-librarian

The skill's SKILL.md will delegate to a Task / general-purpose subagent if one is available, and fall back to running inline in your session otherwise. In the inline-fallback case there is no context isolation — every gh response and file Read lands in the main conversation.

Usage

• Claude Code: /github-librarian <query> — pass scope hints (repo names, owners, refs, paths) inline when you have them.
• Or invoke the github-librarian subagent directly via the Task tool.

Example:

/github-librarian where does anthropics/claude-code define the marketplace.json schema?

More Skills Like This

Found this skill useful? Browse all my hand-crafted ones in the AI Agents skills repo.

License

MIT