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

Annotations already declare the tool as read-only, idempotent, and non-destructive. The description adds useful behavioral context about sorting (newest first), pagination, and the inclusion of storage usage and categories. This augments the safety profile provided by annotations without contradicting them.

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 opening sentence is concise and informative, but the 'When to use' section repeats the same information verbatim, and the parameter section duplicates schema content. This redundancy makes the description less efficient than it could be, though it remains short and readable.

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, read-only tool with no output schema, the description covers the essential context: what the tool does, sorting behavior, pagination, and result content. It could add more detail about error handling or response format, but overall it is adequate for the tool's complexity.

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 100%, and both parameters (page, limit) already have clear descriptions with defaults and maximums in the schema. The description's 'Parameters to validate before calling' section simply repeats this information, adding negligible value beyond the schema.

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's action: 'List all files in the user's Drive' with additional specifics about storage usage, categories, pagination, and sorting. This distinguishes it from sibling fetch_* tools, making the purpose 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?

The 'When to use' section provides clear context for when to invoke this tool (listing files in Drive). However, it does not explicitly mention exclusions or alternative tools for specific file operations, such as get_file_url or send_file, which would differentiate it further.

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