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

Beyond the readOnlyHint annotation, the description discloses the full return contract: page_url lifetime, download_url expiry (1 hour), inline attachment under 100 KB, gzip compression over 50 MB, multi-part splitting with per-part URLs, and a prompt-injection warning about row values. It also notes the tool is free, which matters next to cost-related siblings like estimate_cost.

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?

Front-loaded with the core action, then proceeds through return values, size thresholds, and handling rules in a logical order. Dense but nearly every clause carries operational information; only "Give the links to the user" and "give the user every part" overlap slightly.

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?

With no output schema, the description fully carries the return-value burden, covering both link types, their lifetimes, attachment behavior, compression, and part numbering. An agent can act correctly on the result without further documentation.

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% for the single list_id parameter, which is already documented as coming from create_list. The description adds no further parameter meaning, so the baseline of 3 applies.

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?

"Build a CSV of the whole list" names a specific verb and resource, and clarifies scope (the entire list, not a filtered slice). It does not, however, distinguish itself from siblings like get_rows or export_run, which an agent must resolve on its own.

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?

Usage is implied rather than stated: the tool is for producing a downloadable CSV of a whole list. There is no explicit guidance on when to pick this over get_rows (paginated row access) or when not to export at all, though "do not try to fetch them yourself" gives one clear operating instruction.

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