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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior. The description adds genuine context beyond them: data provenance (NASAA map and model rule, date checked) and an explicit failure mode ("Refuses when the state's status is not confirmed"), which tells the agent to expect a no-result rather than a fabricated answer.

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?

A single dense sentence front-loads the core question and then layers source, input, and failure behavior without filler. It is somewhat run-on, but every clause carries information the agent needs.

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 carries the return-value burden and does so: it enumerates the answers returned (requirement status, effective date, obligations) and notes the checked-date provenance. Nothing an agent needs to call or interpret this tool 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% and the single parameter is fully documented there, so the baseline is 3. The description repeats the accepted input forms (two-letter code or name) without adding format, validation, or edge-case detail beyond the schema.

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 resource (IAR CE requirement for one state) with clear sub-questions answered: whether CE is required, since when, and what it requires. The source (NASAA's IAR CE map and model rule) and scope (one state, not all) distinguish it from the plural sibling iar_ce_states.

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?

The description implies usage by scoping to "one US state or territory" and mentioning accepted input forms, plus a refusal condition. However, it never explicitly names the alternative for multi-state lookups (iar_ce_states) or states when this tool should be preferred, leaving the routing to inference.

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