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

Annotations already cover read-only and closed-world, and the description adds real behavioral context beyond them: the data is free, coverage is limited to 30 cities, county-level (not city-level) FEMA ratings, and disaster declarations exist only 'for verified cities' — a meaningful availability caveat. It does not mention rate limits or freshness, which is a minor gap.

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?

Two dense sentences with no filler; the field list is packed but each item is informative. The leading 'Free.' is slightly odd as a front-load but does state a useful constraint. The county-vs-city caveat is placed last when it could be earlier.

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 one optional parameter, no output schema, and safety already covered by annotations, the description does the needed work: it enumerates return content, explains the omission behavior, and flags the county-level rating caveat. Only the relationship to get_city_pack is left unaddressed.

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 the city parameter's accepted forms (id, name, or 5-digit county FIPS) are already documented. The description's only addition is the omission behavior for listing, which is also in the schema; baseline 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?

States a specific verb-less but precise resource: 'FEMA National Risk Index for the county of one of the 30 largest U.S. cities', and enumerates the returned fields (overall rating and score, per-hazard share/rating/score/expected annual loss, declarations, alert sign-up). This is far from tautology, though it does not explicitly distinguish itself from the similarly named sibling get_city_pack.

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?

'Omit city for the list' gives clear guidance on the listing mode, and the 30-city scope implies when the tool is not applicable. However, there is no explicit when-to-use vs. get_city_pack, and no statement of what to do for a city outside the top 30 besides the implicit scope limit.

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