Search mail

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

Beyond annotations (readOnly, idempotent, non-destructive), the description explains that full_text uses Thunderbird's global index on indexed messages, while other fields are substring per-folder. It also specifies ISO-8601 dates and that results are summaries. This adds meaningful context without contradicting 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?

Four sentences, front-loaded with purpose, followed by critical behavioral details and pagination. No redundant information; every sentence adds value.

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 presence of an output schema, the description covers the essential: search behavior, filter combination, pagination, and when to use mail_get. It lacks explicit mention of folder or account scoping (though schema has account_id and folder_id), but overall is fairly complete for a complex search tool.

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?

With 22 parameters and 0% schema description coverage, the description only mentions full_text, subject, author, body, cursor, and dates implicitly. It does not explain the many other parameters like junk, tags, to_me, folder_id, etc., leaving the agent to infer meaning from parameter names alone.

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 'Search the user's mail' with specific verb and resource. It distinguishes itself from sibling tools like mail_get (retrieve body) and mail_list (list all) by focusing on search with filters. The differentiation from other search tools is implicit through context.

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 explicit guidance on combining full_text with filters, notes that subject/author/body are substring matches, and advises using mail_get for full body. It also explains pagination with cursor. However, it does not explicitly state when to use this tool over alternatives like search_global or mail_list.

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