A small group is using agents. Adoption has spread beyond one person but is not project-wide.
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: 100%. Bars are scaled to that peak, not to 100%.
Which agents
| OpenAI Codex | OpenAI | 76 | 40.9% |
| Claude Code | Anthropic | 45 | 24.2% |
| Cursor Agent | Anysphere | 1 | 0.5% |
Verify it yourself
Sample commits that matched. Every one links to GitHub — check the trailers.
33e4fa72Invalidate computed styles after CSS imports loadOpenAI Codexec6fd5b3Select storage event recipients at mutation timeOpenAI Codexbcc037a8Honor script type and legacy event attributesOpenAI Codex8d7a37fcAvoid quadratic HTML collection iterationClaude Code2920659fFix border width resolutionClaude Code4f374b99Run a connected script when children are inserted into itClaude Code7772347aKeep mixed length + calc() track lists in grid-template-columns (#4241)Cursor Agent
What was excluded
| Commits in window | 186 |
| Merge commits removed | −0 |
| CI / dependency bots removed | −0 |
| Considered | 186 |
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 jsdom/jsdom