Buildkite shipped MCP server tools that put blocking failures first and retry only infrastructure failures, closer GitHub Actions compatibility, and billable active-user usage in the Buildkite API between October 2 and October 9, 2026. Platform teams can now manage organization memberships in Terraform, give each AWS role its own OpenID Connect (OIDC) audience, and move the Elastic CI Stack for AWS Terraform module to agent v4. Agent v4.2.1 and v4.3.0 also skip cached commands and cache Git Large File Storage (LFS) objects, and the Tests plugin v1.1.0 adds manual test selection.