search_messages

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

With no annotations provided, the description carries the full burden. It discloses that the tool returns message summaries and a next_page_token for pagination, indicating read-only behavior. However, it does not mention authentication, rate limits, or whether deleted messages are included (though include_spam_trash parameter hints at it).

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 concise at two sentences, front-loads the core purpose (search messages with Gmail syntax), and efficiently adds the return value and pagination detail. No unnecessary words.

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 complexity (6 parameters with no schema descriptions, no output schema), the description is incomplete. It fails to explain key parameters like max_results, include_spam_trash, account, and password. While it covers the return structure, it leaves many usage details unspecified.

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 schema has 0% description coverage, so the description must explain all 6 parameters. It only indirectly explains 'query' via an example and 'page_token' via the output token, but it omits max_results, include_spam_trash, account, and password entirely. The 'password' parameter is particularly unclear without explanation.

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 searches messages using Gmail query syntax, provides an example, and mentions pagination. It distinguishes from sibling tools like search_threads by specifying 'messages' as the resource.

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 implies usage for searching messages with Gmail syntax but offers no explicit guidance on when to use this tool versus siblings (e.g., search_threads, get_message). No exclusions or alternatives are mentioned.

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