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

Annotations already cover readOnly/idempotent/non-destructive, so the bar is lower, but the description still adds real value: it discloses the return shape at a semantic level (title/subject membership rules tuned for precision over recall, live bill_count, how_to_fetch_bills) and the key limitation that no bill rows come back. It does not discuss pagination or rate limits, keeping it just short of 5.

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 verb and resource, and each sentence carries distinct information (scope, examples, semantics of a topic, what it does not return, what to pair it with). The long parenthetical example list is slightly costly but serves discovery, so it is efficient overall rather than padded.

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?

No output schema exists, so the description carries the burden of describing returns, and it does so (title/subject membership rules, bill_count, how_to_fetch_bills) while also signposting the follow-up path to bills. For a zero-argument, read-only listing tool this is complete.

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?

The tool takes zero parameters, so the baseline is 4. Nothing in the description needs to compensate for parameter documentation, and the empty schema is consistent with a no-argument list tool.

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+resource ('List Bill Commons' curated cross-state topic trackers') and enumerates concrete examples of the topics. It also explicitly distinguishes itself from bill-returning tools, so an agent can tell it apart from search_legislation or get_bill_record without opening any 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?

Explicitly frames the tool as the entry point for 'what subjects does Bill Commons track across all 50 states + DC' and 'how do I get every bill in one', and names the alternatives ('pair it with search_legislation or the REST API's /topics/{slug}'). Both the when and the when-not (it does not return bill rows) are stated.

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