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

Beyond the readOnly/openWorld annotations, it discloses high-value backend quirks: a caller-supplied radius is ignored, only the nearest ~20 stores are returned ordered by distance, and an empty list signals no stores. This is exactly the kind of non-obvious behavior an agent needs and could not infer from schema or annotations.

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?

Front-loaded with purpose and return fields, then the required-parameter note, then the API quirks. Three sentences, no filler, each carrying distinct information.

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?

An output schema exists, so return values need not be enumerated, yet the description still summarizes them usefully. Combined with the API-behavior caveats and full annotation coverage, an agent has everything needed to call this 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% and both lat/lng already carry range descriptions, so the schema does the heavy lifting. The description's 'lat and lng are both required' restates the required array and adds no new syntax or meaning, so the baseline 3 is appropriate.

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+resource ('Adidas physical retail store locator: find the nearest stores') and specifies the returned fields, so the agent knows exactly what it gets. It does not, however, distinguish itself from the sibling 'adidas_store' (singular), leaving ambiguity between two similarly named store tools.

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 the usage context (pass a lat/lng to get nearby stores) and states that both coordinates are required, but it never says when to pick this over adidas_store or any other alternative, nor does it set exclusions. Adequate but with a clear routing gap.

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