get_merchant_info

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is clear. The description adds valuable behavioral context by disclosing the cache-priming side effect, which is a non-obvious consequence of calling this tool. It does not go into potential errors or response details, but the cache note goes beyond mere annotation reiteration.

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, front-loaded with the primary purpose, and every word adds value: the first sentence states the action and scope, the second lists returned fields, and the third (part of the same sentence) explains the cache-priming behavior. No fluff or repetition.

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 zero-parameter read-only tool with an output schema present, the description covers everything needed: what the tool does, what information is included, and an important behavioral note (cache priming). The output schema handles return-value details, so the description is appropriately scoped and 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?

The tool has zero parameters, so the schema leaves nothing to explain. Per the rubric, a baseline of 4 is appropriate when no parameters exist; the description correctly avoids inventing parameter-like details and instead focuses on what data is returned.

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 opens with a specific verb ('Return') and a clear resource ('key information about this Clover merchant'), then enumerates the exact fields (name, address, currency, timezone, country, business type). This clearly distinguishes it from sibling tools like get_merchant_properties and whoami by focusing on a compact set of key merchant 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?

The description conveys when to use the tool by noting it 'primes the internal currency and timezone cache used by all other tools,' implying it should be called early in a session to enable correct formatting in subsequent operations. It does not explicitly mention alternatives or exclusions, but for a zero-parameter getter that is sufficient context.

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