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

With no annotations, the description carries the full burden and does well: it discloses the Standard CONUS fallback when no non-standard rate exists, the 404 behavior for unsupported state codes, case-insensitive partial matching, and the today-default. It omits pagination/response size behavior, so not a 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?

The scope statement leads, followed by filtering and fallback behavior; every paragraph adds actionable information. It is somewhat longer than strictly necessary, with a little redundancy between the opening line and the first sentence.

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 compensates by describing what each result contains (seasonal lodging rate plus M&IE rate) and the inclusion of a verification URL. That is enough for an agent to call and interpret the tool correctly.

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 baseline is 3; the description still adds value by explaining the date-omission default, the matching semantics of `location`, and the effect of `verification_url` on the response. These go slightly beyond the schema's own text.

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 ('Return every GSA destination rate in a state that applies on a specific date') and scopes it to CONUS destination rates. It is clearly distinguishable from the zipcode, destination, and state_year siblings by the state-only, single-date framing.

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?

It explains when rates default to today if `date` is omitted, when to use `location` to narrow results, and that it is CONUS-only with 404 on unknown state codes. It does not explicitly name the sibling tools (e.g. get_gsa_perdiem_by_state_year) as alternatives, which keeps it below a 5.

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