gam_gmail_search_messages

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

The description discloses that userEmail is the DWD impersonation subject, which is behavioral context beyond the schema. However, it does not mention read-only nature, rate limits, or any other behavioral traits, and no annotations are provided.

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 extremely concise with two sentences that directly state the purpose and a key behavioral note. Every word earns its place.

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 4-parameter schema, no output schema, and no annotations, the description lacks details about return format structure, pagination, required scopes, or error conditions. 'Metadata + snippets' is vague.

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 coverage is 50% (query and userEmail have schema descriptions). The description adds a brief note about userEmail's role (DWD), but this is already in the schema. No additional meaning is added for format or maxResults.

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 action (searches) and resource (mailbox) and output (metadata + snippets). It is distinct from sibling tools like gam_gmail_get_message, but does not explicitly differentiate itself.

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?

No guidance is given on when to use this tool vs alternatives. There is no mention of prerequisites, when not to use, or exclusions.

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