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: 41.7%. Bars are scaled to that peak, not to 100%.
Which agents
| Claude Code | Anthropic | 16 | 1.2% |
| GitHub Copilot | GitHub | 12 | 0.9% |
Verify it yourself
Sample commits that matched. Every one links to GitHub — check the trailers.
01b968fbAdd opt-in SortSwitchSections setting (#3749). (#3750)Claude Codee0954474Add missing decompiler-settings resource stringsClaude Codefadcb354Cover ConfigureAwait and [MethodImpl(NoInlining)] in the Async pretty testClaude Codeb1e51638Fix #3894: keep lambda parameter typing consistentGitHub Copilotc6aa9510Handle scoped captures through writable argumentsGitHub Copilotaab8b9b2Fix #3853: infer scoped locals from ref safetyGitHub Copilot
What was excluded
| Commits in window | 1,453 |
| Merge commits removed | −126 |
| CI / dependency bots removed | −12 |
| Considered | 1,315 |
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 icsharpcode/ILSpy