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: 93.8%. Bars are scaled to that peak, not to 100%.
Which agents
| Claude Code | Anthropic | 205 | 58.7% |
| GitHub Copilot | GitHub | 3 | 0.9% |
Verify it yourself
Sample commits that matched. Every one links to GitHub — check the trailers.
84b5ee5aAdd implement-spec skill (in-progress) with its bucket docsClaude Code4f289474chore: add changeset for YAML front-matter fixClaude Code5c89081dfix: quote SKILL.md descriptions with unquoted colonsClaude Codeb843cb5eAdd structured sections for 'what-to-do' and 'supporting-info' in SKILL.mdGitHub Copilot179a14e7Swapped 'backlog' for 'issue trackerGitHub Copilot3e3ca9b9Add initial implementation of design-an-interface skill and linking scriptGitHub Copilot
What was excluded
| Commits in window | 457 |
| Merge commits removed | −102 |
| CI / dependency bots removed | −6 |
| Considered | 349 |
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 mattpocock/skills