job_cancel

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

Annotations already flag this as destructive and non-read-only, and the description goes well beyond them: cancellation is asynchronous (returns cancel_requested), final state is only visible later via job_get, and can become CANCEL_UNCONFIRMED if process groups are not verified gone. It also discloses a real limitation — resources outside the group are not covered — which is essential for an agent to avoid false assumptions.

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-loaded with the action, then the outcome semantics and limitations. Dense but every sentence carries operational value; slightly long, though no sentence is filler.

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?

Given an output schema exists, return-value detail is not strictly required, yet the description usefully explains cancel_requested and CANCEL_UNCONFIRMED. The gap is parameter documentation and auth/permission requirements, which are absent for a 3-parameter mutation tool.

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 0%, so the description carries the full burden for jobId, projectId, and locale, yet it explains none of them beyond an incidental mention of CODESPACE_MCP_JOB_ID in the cleanup advice. The patterns and enum in the schema are uninterpreted, leaving the parameter meaning largely unexplained.

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 ('Request cancellation') and immediately qualifies the scope by describing what cancellation does and does not cover. An agent can distinguish it from job_get, which it explicitly names as the follow-up verification tool.

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?

The description makes the workflow explicit: request here, verify via job_get, and note that resources outside the process group (containers) must be handled separately in cleanup steps. It gives clear context but does not spell out when cancellation is preferable to alternatives such as letting a job finish.

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