Search emails

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

With no annotations, the description carries the burden of behavioral disclosure. It usefully reveals case-insensitive matching, inclusive/exclusive date boundaries, and server-side execution via IMAP SEARCH. However, it does not mention whether the operation is read-only, how results are returned, or any performance/rate-limit considerations.

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 compact and front-loaded, with three sentences each carrying meaningful information. It avoids fluff and redundancy, though it could have used the space to cover more parameters.

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 8 parameters, no output schema, and no annotations, the description is only partially complete. It provides essential date semantics and matching behavior, but omits default folder behavior, limit handling, how multiple criteria combine, and what the search returns.

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 only 25%, so the description must compensate for the 6 undocumented parameters. It explains only since and before in depth; to, from, subject, text, limit, and folder receive no added meaning beyond the raw schema, leaving a significant gap.

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 tool's action ('Search messages') and adds precise semantics ('case-insensitive substring match'), which distinguishes it from the sibling list_emails. However, it does not name the sibling explicitly, so it falls just short of full differentiation.

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?

There is no guidance about when to use this tool versus list_emails, get_email, or other siblings. The description does not mention that this tool is for filtering by criteria while list_emails might be for broad listing, nor does it state any exclusions or prerequisites.

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