cvs_store_locator

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

With no annotations provided, the description fully carries the burden. It discloses that it returns only general store info, not pharmacy-specific data, and notes the regional availability limitation (US/US-territory egress only, upstream error otherwise). It also explains parameter precedence behavior, which is a key behavioral trait.

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 well-structured and front-loaded with the core purpose. It flows logically: what it does, what it returns, what it excludes, parameter details, and regional constraint. Each sentence contributes new information without redundancy, making it efficient despite its length.

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?

For a tool with 5 parameters, no output schema, and no annotations, the description covers the essential aspects: output fields, scope limitations, parameter precedence, service filtering, and regional availability. It could be improved by mentioning result limits or pagination, but these are minor gaps for a store locator tool.

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% (all parameters have descriptions). The description adds value beyond schema by explaining the precedence of zip/address/lat-long and clarifying that the service param uses the same vocabulary as the response's services field, plus the one-service-per-request rule. This goes beyond the schema's basic descriptions.

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 clearly states the tool's function: 'Returns nearby CVS store locations' with specific input options (ZIP, address, lat/long) and output fields (address, phone, fax, distance, hours, has_pharmacy, services). It distinguishes itself from general store locators by specifying CVS-specific data and explicitly excluding pharmacy details.

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?

Provides clear context on when to use the tool: for general store information, not pharmacy data. It also details parameter precedence (zip wins, then address, then lat/long) and the optional service filter. However, it does not explicitly name alternative tools or state 'use this instead of X', though the scope limitation effectively communicates what not to use it for.

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