Since ~05:00 UTC on 2026-07-08, triggering a pipeline via POST /2.0/repositories/{workspace}/{repo}/pipelines with custom variables started returning 400:
“Variables exceed the maximum allowed count or total size. Maximum count: 50, Maximum total size: 10240 bytes.”
…for requests that succeeded fine before that time. Nothing changed on our side.
What’s confusing:
- The 10,240-byte total-size limit contradicts the documented limits — the Variables & secrets page states 100 KB for shared variables and 120,000 chars per custom value. 10 KB appears nowhere in the docs.
- It’s a hard, clean cliff: requests whose combined variable values are <= 10,240 bytes succeed; > 10,240 bytes fail 100% of the time (verified across hundreds of triggers).
- Onset was sudden and hit many separate workspaces at the same time.
- No matching entry in the developer changelog.
Questions:
1. Was the total-size limit for API-trigger variables intentionally reduced to 10,240 bytes? If so, where is it documented?
2. If not intentional, is this a known regression, and is a fix/rollback planned?