Explore Claude Code GitHub Actions integration (@claude mentions)

[dcwhite]

Summary

Explore setting up Claude Code GitHub Actions (the @claude GitHub App integration) for this repo, so that tagging @claude in an issue, PR comment, or PR review comment can trigger Claude Code to analyze code, answer questions, implement changes, and open/update PRs directly from GitHub — without a maintainer needing to pull the branch locally first.

What it is

A GitHub App + reusable GitHub Actions workflow published by Anthropic. Once installed on a repo, commenting @claude <request> anywhere (issue, PR description, PR review comment) triggers a workflow run that:

• Checks out the relevant branch/PR
• Reads the repo's CLAUDE.md (if present) for project conventions
• Runs Claude Code in an agentic loop against the request
• Posts its findings back as a comment, and/or pushes commits / opens a PR, depending on what was asked

Proposed setup steps

1. Run /install-github-app from a local Claude Code session with admin access to SCIInstitute/SCIRun. This walks through:
   • Installing the GitHub App on the repo (or org)
   • Adding an ANTHROPIC_API_KEY repo secret
   • Committing a starter workflow file under .github/workflows/ (e.g. claude.yml)
2. Review the generated workflow YAML before merging — decide which events should trigger it (issue comments only? PR review comments too? all pushes?) to control cost/noise.
3. Do a scoped test: open a throwaway issue, tag @claude, confirm it responds sanely and follows repo conventions (build system quirks, Qt5/Qt6 split across platforms, reusable-build.yml, etc.).
4. Decide on guardrails:
   • Should it be allowed to push directly to branches, or only ever open new PRs?
   • Any restriction on who can trigger it (e.g. only org members, to avoid random public users burning API quota via issue comments)?
   • Should CLAUDE.md be added/expanded to give it explicit build/test instructions for this CMake + Qt + Python multi-platform project?

Prerequisites

• Repo admin access on SCIInstitute/SCIRun (org-owned repo, so this may need an org owner rather than a personal fork)
• An Anthropic API key with budget/quota allocated for this use
• GitHub Actions already enabled (it is — see .github/workflows/*.yml)

Open questions

• Who owns the API key / billing for this — personal key or an org-level key?
• Do we want this on by default for all issues/PRs, or opt-in per-issue (e.g. only when explicitly tagged, never auto-triggered on push)?
• Cost ceiling / rate limiting — GitHub Actions minutes + Claude API token usage both apply per invocation.

References

• Claude Code GitHub Actions docs: https://code.claude.com/docs/en/github-actions.md