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

With no annotations, the description carries the full burden and does so: it discloses caching ('may be served from an earlier reading'), the readAt recency signal, refusal behaviour for non-legal documents, the ~20,000-60,000 vs ~1,000 token cost profile, and the not_stated guarantee that prevents fabricated promises. It also warns that plain fetches of JS-rendered pages return empty shells silently — a failure mode an agent could not infer.

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 purpose and output shape, then guarantees, then caching, then exclusions — a logical order with no filler sentences. It is longer than most single-parameter tools warrant, and the closing 'legal advice' line partly repeats the disclaimer already implied, but each block carries distinct 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?

For a one-parameter tool with no output schema and no annotations, the description supplies the return contract (verdict, eight answers, up to five findings with quotes), the trust model (not_stated handling, verbatim quoting), and the caching/recency caveat. Nothing an agent needs to call it correctly or interpret the result is missing.

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?

Only one parameter at 100% schema coverage, so the baseline is 3; the description earns above baseline by reinforcing that the URL must be the published policy page rather than a homepage or a user-pasted document. It does not add URL format/normalisation details beyond that.

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?

Names a concrete verb+resource ('Read one privacy policy or terms-of-service page') and specifies the exact output shape: a grounded verdict, eight fixed yes/no/partly/not-stated answers, and up to five quoted findings. It also positions itself relative to siblings by citing policy_changes_since and noting the fixed question set that makes reports comparable across services (compare_policies' territory).

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?

Explicitly states when to use it over the obvious alternative ('Use this instead of fetching and reading the page yourself') and backs that with cost/context reasoning. It also lists concrete exclusions: non-legal documents, general summarisation, user-pasted documents, and legal advice, plus the condition under which to escalate to policy_changes_since.

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