worker_cancel

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

Annotations already declare readOnlyHint=false and idempotentHint=true, so the safety profile is partly covered. The description adds genuinely useful behavior: only the lifecycle record is written and no OS processes are terminated, which prevents an agent from assuming cancellation has runtime side effects. It stops short of saying what happens when the job is not in a queued state.

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?

Two short sentences, front-loaded with the action and followed immediately by the most decision-relevant constraint (no process killing). 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 one-parameter mutation tool with no output schema, the description covers action, scope, side-effect boundary, and safety. The remaining gap is the non-queued case (error vs. idempotent no-op) and how to obtain a valid id, which are minor but non-trivial.

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 0% and the single 'id' parameter has no description, so the description must carry the load. It only indirectly identifies the id as a job identifier via 'a queued ... worker job'; it does not state the id format or source (e.g. from worker_list/worker_enqueue).

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 names a specific verb+resource: marking a queued no-shell local worker job as cancelled. The qualifiers 'queued' and 'no-shell' scope it apart from worker_enqueue, worker_status, and worker_run_read_only, though no sibling is named explicitly.

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?

Applicability is implied by 'queued' and reinforced by 'never kills processes', which signals this is not the tool for stopping a running job. However, there is no explicit when-to-use statement, no named alternative, and no guidance on what to do for non-queued jobs.

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