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

With annotations declaring destructive and non-readonly, the description adds valuable behavioral context: the tool can only cancel pending/open requests, not claimed/completed ones. It also implies idempotency (already in annotations) but doesn't elaborate on side effects (e.g., what happens to the request, permissions). This is good additional transparency beyond the annotations.

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 concise (two sentences) and front-loads the core action and the key constraint. Every sentence earns its place, though it could be slightly more structured with bullet points, but it's efficient.

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 destructive cancellation tool with no output schema and 0% parameter coverage, the description covers the main behavioral constraint but fails to explain the required parameters or any authentication/permission needs. It's minimally adequate but leaves gaps an agent would need to infer from the schema.

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%, and the description provides no information about the two parameters (request_id, status_token)—their purpose, format, or how to obtain them. This is a significant gap given the low schema 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 clearly states a specific verb and resource ('Cancel a request') and scopes it to the Japan physical verification context via the title. It distinguishes from siblings by focusing on cancellation of a verification request, though it doesn't explicitly name alternative tools.

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 provides clear when-to-use guidance ('only while it is pending manual review or open') and an exclusion ('claimed or completed work cannot be cancelled'). This gives strong context, though it doesn't name alternative approaches for non-cancellable states.

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