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

Annotations already declare the tool as read-only, idempotent, open-world, and non-destructive. The description adds that it reports availability, freshness, and provenance, especially when coverage is unknown, but it does not add further behavioral details such as rate limits, authentication needs, or return format.

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 description is a single tight sentence with the verb and resource front-loaded. Every phrase contributes to purpose or usage context, with no wasted text.

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?

Given a simple one-parameter read-only tool with annotations and an output schema, the description is nearly complete. It explains what is returned at a high level, though it could be slightly fuller on when to choose this over sibling tools.

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 0%, so the description carries more burden for the single required parameter. It identifies the parameter as a ZIP code, but it does not clarify the 5-digit format or other ZIP-specific semantics beyond what the schema pattern already enforces.

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?

The description uses a specific verb and resource: getting program availability, freshness, and provenance for a ZIP. It is clear what the tool does, but it does not explicitly distinguish itself from siblings such as check_rebates or get_energy_profile.

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 phrase 'without guessing when coverage is unknown' implies a use case for checking coverage gaps, but the description does not explicitly say when to use this versus the sibling tools. Usage is implied rather than directly stated.

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