get_discount

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

No annotations are provided, so the description carries the burden. It says 'Get' which implies a read-only operation, but it does not explicitly state that it does not modify data or mention any permissions, rate limits, or side effects. It lists the returned fields, which is useful, but it does not disclose any behavioral constraints beyond that. For a simple read, a 3 is appropriate.

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?

A single, front-loaded sentence with zero wasted words. It states the action, the resource, the details returned, and the lookup method, all in one concise line.

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?

Given the simplicity (one parameter, no output schema, no annotations), the description adequately explains what the tool returns (type, value, usage limits, validity window). It does not mention error cases or response format, but for a basic get-by-id tool, the information is sufficient. The note that the id/code comes from list_discounts in the schema adds context, though the description itself could mention that the identifier is required (since schema marks it as not required).

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 schema coverage is 100% and already documents the parameter as 'id or code (from list_discounts)'. The description repeats 'by id or code' but does not add new semantic meaning beyond the schema. The description does clarify that it returns full details, but that relates to output, not the parameter. Baseline 3 is appropriate because the schema handles parameter documentation.

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 ('Get'), names the resource ('one discount's full details'), and enumerates the exact fields returned (type, value, usage limits, validity window). It clearly distinguishes from sibling tools like list_discounts (which lists) and update_discount (which modifies) without ambiguity.

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?

It clearly implies this tool is for retrieving a single discount's details, which differentiates it from list_discounts and mutation tools. However, it does not explicitly say when NOT to use it or mention alternatives, though the schema parameter hint ('from list_discounts') reinforces usage for individual lookup. It is adequate but lacks explicit exclusions.

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