Capabilities

How headgate keeps backend and feature claims honest.

Headgate maintains a capability register alongside its conformance suite. A completed or partial capability must cite a named assertion, test, or executed scenario in the evidence ledger. The validation gate rejects claims whose evidence no longer resolves.

Browse implemented features

Use the public feature index to find the guide for each implemented capability area.

Status	Meaning
Complete	The capability is implemented and its cited conformance evidence passes.
Partial	A documented subset is implemented and the evidence identifies that boundary.
Missing	The capability is not implemented and must not be advertised at runtime.
Deferred	The capability was deliberately postponed with its rationale recorded.

Runtime capabilities

Backends also advertise optional runtime capabilities explicitly:

• inspection and operator control;
• application transactions;
• push notifications;
• result, output, and progress storage.

A missing capability produces an explicit unsupported error or absent upcast. It is never a public method that silently does nothing.

Mechanical checks

• scripts/check-evidence.py resolves every completed and partial claim.
• scripts/check-inventory.py fails when a tracked test disappears.
• scripts/run-scenarios.py executes YAML scenarios against live stores.
• scripts/test-admission.sh compares backend and language behavior.

Verification commands

Run the same evidence and conformance gates used for feature claims.