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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds valuable behavior beyond annotations: the URL is short-lived, points at raw file content, and works without authentication until expiry. Exact TTL and error behavior remain unspecified, but the added context is strong.

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?

Two tightly written sentences with no filler. The core action and return value are front-loaded, followed by essential behavioral context.

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 a two-parameter, read-only tool with full schema documentation and no output schema, the description is complete enough. It explains how to obtain the input, what is returned, and the important auth-free, short-lived URL behavior.

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 parameters are already documented. The description reinforces that fileId comes from drive_list_files but adds no meaning beyond the schema, and it does not discuss the disposition parameter, so baseline 3 is appropriate.

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?

States a specific verb and resource: return a presigned download URL for a Drive file. It distinguishes the tool from drive_list_files by naming that sibling as the source of the file id, and the operation is clearly not a list or mutation.

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?

Provides clear context by telling the agent to get the file id from drive_list_files, implying a prerequisite workflow. It does not explicitly name alternatives or when not to use the tool, but the usage context is clear for a simple retrieval tool.

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