Understand and safely change heartbeat interval, stuck threshold, and timeout constants — client cadence, server detection math, frontend signal.
Add a new AnnotationKind — proto, storage, ingress RPC, optional downstream delivery to agents, frontend authoring UI, tests.
Add a new agent Capability — proto enum, client advertisement, server ingest, frontend gating in the control UI.
Add a new ControlKind — capability advertisement, client handler, server routing, ack semantics, frontend button, and tests — all the way through.
Add a new drift kind end-to-end. Goldfive owns the detector + enum; harmonograf reflects the kind through the intervention aggregator and the UI timeline.
Script a complex multi-turn FakeLlm scenario — function calls, tool chains, drift events, side-effect hooks, partial responses — for deterministic adk test coverage.
Add a field to a proto message end-to-end — proto edit, regen, client+server converters, frontend types, tests, and sqlite migration if persisted.
Add a new reporting tool. Reporting tools moved to goldfive post-migration; harmonograf no longer owns `client/harmonograf_client/tools.py`. This skill redirects to goldfive and covers the harmonograf-side touchpoints.