Retrieve a refund

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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is fully covered. The description adds nothing beyond them — no note on behavior for an unknown or malformed id, and no indication of what a refund record contains. The only extra detail, the `re_…` id prefix, is already in the schema.

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?

Very short and front-loaded, but the first sentence is a verbatim duplicate of the title and the second sentence repeats the verb and resource again. Roughly half the text is redundant restatement rather than added 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?

For a single-parameter read tool with full annotations, complete schema coverage, and no output schema, the definition is minimally sufficient to call correctly. It falls short of explaining the lookup-key distinction from its two closest siblings, which is the main open question an agent would have.

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 the single parameter is fully documented, so the baseline is 3. The description's mention of the `re_…` format merely restates the schema description and adds no new meaning such as a valid/invalid example or a partial-id capability.

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 ("Retrieve a refund") and qualifies the lookup as by id, which implicitly separates it from get_refund_by_reference and list_refunds among the siblings. It doesn't explicitly name those alternatives, but the lookup key is unambiguous.

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?

No guidance on when to use this versus list_refunds (browse/unknown id) or get_refund_by_reference (lookup by external reference). The agent must infer the routing from the id argument alone.

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