Skill: api/compatibility-check

Purpose

Determine whether an API change is:

• backward-compatible
• conditionally compatible
• breaking

And make that status explicit before shipping.

Inputs

• Old contract
• New contract
• Known consumers (if available)

Outputs

• Compatibility assessment:
• compatible / breaking / unsafe
• Explicit list of breaking changes (if any)
• Recommendation:
• proceed
• version
• block

Non-goals

• Modifying contracts
• Updating clients
• Implementing migrations

Workflow

1) Compare old vs new contract shapes. 2) Identify removed or behaviorally changed fields. 3) Assess consumer impact. 4) Emit a clear compatibility verdict.

Checks

• All removals and type changes enumerated
• Verdict is explicit and justified

Failure modes

• Missing baseline contract → block and request one.
• Ambiguous change → recommend meta/spec-sculptor.

Telemetry

Log:

• skill: api/compatibility-check
• verdict
• affected_consumers
• outcome