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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description earns extra credit by disclosing return content (requested-order rows, missing IDs, total estimated bytes, provenance) and the key constraint that no geometry is hosted or downloaded, which is not derivable from annotations.

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?

Three sentences, front-loaded with the action and cardinality, then the return shape, then the non-goal. Every clause carries information; nothing is restated from title or schema.

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 steps in to enumerate the return payload and the provenance field, and it clarifies that no geometry is transferred. For a read-only, open-world lookup with complete parameter documentation, nothing an agent needs to call or interpret it correctly 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 description coverage is 100%, so both parameters are already fully documented and the baseline is 3. The description reinforces the '2-10 exact' cardinality and precision requirement for dfirm_ids but adds nothing for response_format beyond what the enum description provides.

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 (compare) and resource (FEMA NFHL inventory units) with a hard-bound cardinality (2-10) and the exact comparison axes (coverage freshness, advertised download size). It also names the sibling it is not (flood_zone_lookup) for the point/address case, so an agent can route without opening sibling schemas.

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 routes a concrete alternative scenario to flood_zone_lookup, which prevents a common misuse. It does not, however, distinguish this from the closer siblings fema_nfhl_get_inventory_item, fema_nfhl_search_inventory, or fema_nfhl_summarize_state_inventory, so the comparison-vs-single-lookup boundary is left to inference.

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