Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Adds substantial context beyond the annotations: the side-effect records created (callback.replayed, plus callback.forwarded and connector.request.completed appearing against the original event id), the fact that faults do not act on a replay, and a hard cap of 200 per run. These are operational constraints the annotations cannot express.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loads the action and goal, and every subsequent sentence carries a distinct operational fact (preconditions, recording behavior, fault exemption, rate cap). The opening sentence is long and compound, but nothing is redundant.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a two-parameter, no-output-schema tool, the description covers purpose, preconditions, side effects, and limits completely. Nothing an agent needs to invoke it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 50%: event_id is documented in the schema, run_id is not. The description compensates meaningfully by constraining what event_id may be (a callback.received on a connector route with an active run; obtained from rig.event.list or rig.event.wait), which is more than the schema states.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('forward a callback ... to its connector route again, exactly as recorded') plus the intent (proving idempotence). It is clearly distinguishable from siblings like rig.event.list, rig.event.wait, and rig.connector.prepare.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit preconditions: the event must be a callback.received on a resource with a connector route, and the run must be active. It does not name the alternative tool for fetching candidate event ids in prose, but the schema description for event_id points to rig.event.list / rig.event.wait, so routing is covered.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.