find_zip_codes_in_radius

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds that results include distance from the center. However, it says 'Find all' while the limit parameter (default 100, max 500) may truncate results, and it does not disclose whether the center ZIP itself is included or how units affect the distance values.

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 two sentences long, directly states the purpose and return format, and contains no filler or redundant information. Every word adds value.

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 does partially explain the return value ('Returns each nearby ZIP with its distance from the center'). However, it omits important behavior such as the limit truncation, whether the center ZIP appears in results, and how unit affects output. For a moderately complex 5-parameter tool, this is adequate but not fully complete.

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% with clear descriptions for every parameter. The description only restates 'center ZIP code' and 'radius' implicitly, adding no new semantic information beyond what the schema already 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?

The description uses a specific verb ('Find') and names the exact resource ('all ZIP codes within a given radius of a center ZIP code'). This clearly distinguishes it from sibling tools like lookup_zip_code (single ZIP lookup) and calculate_zip_code_distance (distance between two specific ZIPs).

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 clearly implies when to use the tool: when you need all ZIP codes around a center point. It does not explicitly list alternatives or exclusions, but the purpose is specific enough to guide selection without confusion.

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