GitHub Actions "too many annotations" (only 10 shown)

GitHub limits how many annotations it surfaces per step (10 of each level are shown in the UI, with a per-run cap). A noisy step appears to "lose" warnings or errors because the rest are truncated, not because they vanished.

What this error means

A step reports "X more annotations" or only the first ten warnings/errors are visible despite many being produced.

github-actions

Annotations
10 errors and 0 warnings
... and 37 more annotations were not shown.

Common causes

Step emits more than the displayed annotation limit

A linter or matcher produced many problem annotations, but only the first ten per level appear in the UI.

How to fix it

Surface the full results elsewhere

Write the complete tool output to the job summary or upload it as an artifact so nothing is hidden.
Reduce annotation noise by failing fast or limiting matchers to the most important issues.
Re-run.

.github/workflows/ci.yml

- run: npm run lint -- --format json > lint.json || true
- run: cat lint.json >> "${GITHUB_STEP_SUMMARY}"
- uses: actions/upload-artifact@v4
  with:
    name: lint-report
    path: lint.json

How to prevent it

Publish full tool output to the job summary or an artifact, not just annotations.
Keep annotation volume low so the most important problems stay visible.