Buildkite MCP Server updates

A few things have shipped in the Buildkite MCP Server since list_tests arrived in August.

Read the steps a dynamic pipeline uploaded

You can now ask your agent what actually ran in a dynamic pipeline. list_step_uploads returns a build's uploads, most recent first, with the state of each one, the job that sent it, and the reason for any rejection. get_step_upload returns a single upload's pipeline as YAML. get_build points agents at both, so an agent debugging a build finds them on its own.

Uploads stay readable for about 30 days, until the build reaches its maximum lifetime.

Know you've seen every failure in a build

get_build_failure_summary now returns job_state_counts, a tally of every job in the build by state. An agent can check that against the problem jobs it was handed and know it has the whole picture, rather than calling list_jobs to make sure nothing was missed.

Manage cluster secrets

Getting a new pipeline running means getting its secrets in place, which has always been a job for a person. create_cluster_secret adds a secret to a cluster, so that part can go to your agent.

list_cluster_secrets and get_cluster_secret cover the other direction. They return a secret's key and description but never its value, so an agent chasing a build that failed on a missing secret can name the problem without seeing the secret itself.

There's one thing to check before you let an agent near this. Toolsets default to all, so an agent holding a write_secrets token can create secrets. To stop that, run the server with --read-only.

Find the test suite behind a pipeline

Ask your agent about a pipeline's tests and it no longer needs you to tell it which suite they're in. list_test_suites_for_pipeline returns the Test Engine suites with runs attributed to a pipeline, so the agent finds the right one and carries on to the tests themselves.

Report a tool that gets it wrong

We want to hear when a tool gives your agent a bad answer. Run the report_issue prompt afterwards and it writes the report for you: what you were after, which tools ran with what arguments, and what came back. It fills in the server version and your client, and redacts tokens and credentials.

Paste it into a new GitHub issue or send it to Buildkite support.

All of this is in the current release, v1.22.0.