cancel_run

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

With no annotations, the description carries the full behavioral burden. It usefully discloses the key trait that cancellation is terminal and irreversible, but says nothing about permission requirements, idempotency, or what happens when the run is already finished.

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?

One short sentence, front-loaded with the action and immediately followed by the most important caveat. Nothing is wasted.

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 simple two-parameter cancel with no output schema, the description covers the essential irreversibility note. However, with no annotations at all, it leaves gaps around authorization, behavior on non-active runs, and idempotency that an agent would benefit from knowing.

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 description coverage is 100% for both required parameters (agent id, run id), so the schema already documents them fully. The description adds no parameter-level meaning beyond the schema, which matches the baseline 3 for full coverage.

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?

The description gives a specific verb+resource ('cancel the active run') and clarifies scope with 'active'. It does not name or contrast with any sibling, but the action is unambiguous and distinct from the read-oriented siblings like get_run or list_runs.

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?

There is no guidance on when to cancel versus alternatives such as steer_agent or letting a run finish, nor any prerequisites or error conditions. The only context is the consequence, not the selection criteria.

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