task_cancel

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

Annotations already indicate a non-destructive write operation. The description adds valuable context: it stores task metadata only and does not start or execute an agent, and it is isolated by project_path. These details help an agent understand the scope and side effects, though it doesn't cover state requirements or response format.

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?

The description is brief, but the first sentence is awkwardly structured and not front-loaded with a clear action verb. The second sentence is clear, but the overall flow could be improved for an agent scanning for purpose.

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 cancellation tool, it covers the metadata-only nature and project isolation, but it omits important details such as what happens to an already running task, whether cancellation is reversible, or if the task must be in a certain state. With annotations and full schema coverage, the description is adequate but has clear gaps.

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 100%, so the schema fully documents all parameters. The description's note about isolation by project_path reinforces the schema but adds little new meaning. With the schema doing the heavy lifting, the baseline of 3 is appropriate.

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 says 'cancel' but does not explicitly state that it cancels a task. The phrase 'Use when tracking persistent work across Codex sessions: cancel' is vague and does not follow a clear verb+resource pattern. The tool name helps, but the description alone is only minimally clear about what is being cancelled.

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?

It implies a context for use ('when tracking persistent work across Codex sessions') but does not name alternatives like task_complete or task_update, nor does it specify when not to use this tool. The note about not executing an agent adds some guidance, but the overall usage direction is implied rather than explicit.

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