wait_for_email

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

The description discloses blocking/polling behavior and that it returns the first matching message. However, with no annotations provided, it omits important behavioral details such as what happens on timeout and whether the returned email is consumed or remains in the mailbox.

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 sentences with the mechanism front-loaded, followed by the return behavior and a concrete use case. There is no filler; 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?

The description is adequate for calling the tool given full schema coverage and a clear purpose. However, since there is no output schema and no annotations, the timeout/failure behavior and the structure of the returned message are left unspecified, creating a meaningful gap.

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?

All 5 parameters are fully documented in the input schema (100% coverage), so the baseline is 3. The description adds no parameter-specific meaning beyond the schema's own descriptions.

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 verb ('Block'), a resource ('matching email' in the mailbox), and the return value ('first matching message'). This clearly distinguishes it from sibling retrieval tools like get_messages, which list existing messages rather than waiting for a new one.

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 provides clear context: 'Useful for waiting for verification emails during signups.' It implies when to use the tool but does not explicitly mention alternatives or when not to use it, so it stops short of a 5.

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