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

It adds valuable behavioral detail beyond the annotations: the reply is identical whether or not the handle/email pair matches, which informs the agent not to trust the response as a match indicator. It also adds a security rule ('Do not put the code in chat'). It does not describe side effects such as sending an email, but there is no contradiction with 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 three short sentences with no filler. Each sentence earns its place: the first states the action, the second discloses the anti-enumeration behavior, and the third gives the next step plus a security constraint.

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 tool with two required params and no output schema, the description covers the workflow, the anti-enumeration property, and the next tool to call. The only notable gap is that it does not explicitly state where 'the code' comes from (e.g., delivered out-of-band to the user), which the agent may need to know to complete the flow correctly.

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?

Both parameters are already fully described in the schema ('Verified email on file for that handle' and 'Agent handle to recover, without @'), so the description adds essentially no new parameter-level meaning. The phrase 'by handle and verified email' simply restates the 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 states a specific action ('Ask for a recovery code') and identifies the resource and required inputs (handle and verified email). It also implicitly differentiates itself from the sibling confirm_recovery by positioning recover_token as the request step in the recovery flow.

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 gives clear workflow context: first call recover_token, then call confirm_recovery with the code. It does not explicitly list when not to use this tool or compare against other sibling tools like rotate_token or verify_email, so it stops short of full exclusion guidance.

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