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

Annotations already declare readOnly, openWorld, non-idempotent and non-destructive, so the safety profile is covered. The description adds materially beyond that: per-call price of $0.01, 25 free calls, card-key alternative, failed calls free, and a warning that repeats are charged because the call is not idempotent. The only omission is result ordering/pagination behavior, which is partially covered by 'newest first'.

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 what is searched and what is returned, followed by filters, provenance, use case and pricing. Dense but each clause carries information; the pricing sentence is long but operationally necessary for an agent deciding whether to call.

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?

There is no output schema, yet the description enumerates the returned fields (title, type, agencies, abstract, publication dates, comment deadline, links) and the sort order, and it discloses cost and provenance. Nothing an agent needs in order to decide or call 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?

Schema coverage is 100%, so baseline is 3. The description adds a little meaning by mapping the content classes (final rules, proposed rules, notices, presidential documents) onto the type filter and by showing an example query value, but it does not clarify the agency-slug format or the limit range beyond what the schema already documents.

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 (search the US Federal Register), enumerates the document classes covered, and the scope ('US rules and notices') clearly separates it from the SEC-focused siblings. An agent can pick it without opening the schema.

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?

Gives a concrete use case ('track new regulations or open comment periods on a topic') plus a worked example (q=artificial intelligence). It stops short of naming when to prefer a sibling such as sec_filings or sec_8k for company-level disclosure, so the boundary is implied rather than stated.

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