search_emails

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

The phrase 'using Gmail search syntax' adds useful behavioral context: queries should use Gmail-specific operators like 'from:' or 'subject:'. However, there are no annotations, and the description does not explicitly state that the operation is read-only, mention authentication or scope, or describe what the returned results contain.

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 a single, front-loaded sentence with no filler. 'Search for emails' is somewhat redundant with the tool name, but 'using Gmail search syntax' is the key differentiating information and is placed immediately, making the description appropriately compact.

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 simple two-parameter search tool with an output schema, the description provides the core purpose and query syntax. However, it omits usage guidance, any indication of read-only behavior, and any context about what scope of emails is searched, leaving the agent to rely on schema and sibling names.

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 100%, so both query and max_results are already documented in the schema. The description adds value by clarifying that query uses Gmail search syntax, but it adds nothing about max_results or result limits, so the schema carries most of the parameter burden.

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 clear verb and resource: 'Search for emails', and adds the specific query mechanism 'using Gmail search syntax'. It does not explicitly differentiate itself from sibling tools, but list_email_labels, download_attachment, and batch_modify_emails are obviously different operations, so the purpose is still unambiguous.

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 instead of list_email_labels, download_attachment, or batch_modify_emails, and no mention of when not to use it. An agent would have to infer the appropriate choice purely from sibling tool names, which is minimal implied guidance.

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