search_emails

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

With no annotations provided, the description carries the burden. It discloses that it returns message IDs (not full emails) and uses Gmail's query syntax. However, it does not mention any side effects, rate limits, authentication requirements, or error conditions.

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 two sentences: the first explains the query syntax, the second clarifies the return value and suggests a next step. It is concise and front-loaded with essential information.

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 low complexity (no output schema, no nested objects), the description covers the key aspects: what it does (search with query syntax), what it returns (message IDs), and what to do next (use get_email). It could mention pagination or result limits, but the maxResults parameter implies a limit.

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 0%, so the description must add value. It explains the 'query' parameter with an example of Gmail syntax, but does not explain 'maxResults' beyond what its name and constraints imply. The addition is helpful but incomplete.

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 it searches Gmail using Gmail's query syntax, provides an example, and specifies it returns message IDs. It distinguishes from sibling tools like list_emails (which likely lists without query) and get_email (fetch full email).

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 tells the user to use Gmail query syntax and to follow up with get_email to fetch the actual email. It implies when to use this tool, but does not explicitly contrast with sibling tools like list_emails for basic listing.

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