release_number

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

No annotations are provided, so the description carries full burden. It discloses the main behavior (releasing a number) and emphasizes calling even on error to avoid capacity issues. However, it does not mention whether the release is irreversible or if there are any side effects, which would be helpful for full transparency.

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 only two sentences with no unnecessary words. The critical usage instruction is front-loaded, making it immediately actionable. Every sentence earns its place.

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 the tool's simplicity (one parameter) and the existence of an output schema, the description provides sufficient behavioral context (always call even on error). It is complete enough for an agent to use correctly, though it could optionally mention what the response looks like.

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?

The context indicates 0% schema description coverage, meaning the schema does not provide parameter descriptions (though the schema actually has a description for session_id, but according to context it is 0%). The tool description does not add any meaning to the single parameter (session_id) beyond what is in the schema, failing to compensate for low 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 the action 'Release a provisioned number back to the pool.' It uses a specific verb ('release') and resource ('provisioned number'), distinguishing it from sibling tools like provision_number (which allocates) and list_numbers (which lists).

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 explicitly instructs to 'Always call this when you are done with the session — even on error — to avoid consuming pool capacity unnecessarily.' This provides clear when-to-use guidance and a rationale, effectively differentiating from alternatives.

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