One person is driving this. The headline number reflects a single contributor's workflow, not a project-wide shift.
Assisted or autonomous
Assisted — a developer’s identity authored the commit and the agent added itself as co-author. The agent ran git commit during a working session, with a person there. Autonomous — a bot identity is the author, no human in the loop. Across the whole index, 93.7% of agent commits are assisted.
Agent share by month
Peak month: 96%. Bars are scaled to that peak, not to 100%.
Which agents
| Claude Code | Anthropic | 175 | 39.5% |
| GitHub Copilot | GitHub | 28 | 6.3% |
Verify it yourself
Sample commits that matched. Every one links to GitHub — check the trailers.
3f1b272aResolve first-party Code Quality standard findings (#6714)Claude Code10673856fix(resolver-auth): treat quote-only netrc login as empty on Python 3.10Claude Codec9135113fix(manifest-cache): retry os.replace on Windows ERROR_ACCESS_DENIED with Claude Code01ad9ae8refactor(resolver): narrow backend settings fallback handlingGitHub Copilot9033a63afix(resolver): stamp selected backend onto resolver requestsGitHub Copilotd91347c4docs: fix stale references in venv_locator and news fragmentGitHub Copilot
What was excluded
| Commits in window | 569 |
| Merge commits removed | −106 |
| CI / dependency bots removed | −20 |
| Considered | 443 |
Bots are excluded from the denominator entirely. Counting dependabot as “AI-written code” is the fastest way to produce a meaningless number.
How this was measured
Measured over February–August 2026, cloned directly. Detection is deterministic string matching against signatures agents write about themselves — no heuristics, no style analysis. Merge commits and CI bots are excluded from the denominator. The figure is a floor: squash merges strip trailers, so real usage is higher. Contributor counts are aggregate — no individual is named.
Run it yourself: npx qmmit-cli pypa/pipenv