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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering safety. The description adds the specific behavior of the 'items' flag (returning covered products instead of code detail), which is useful. However, no additional traits like pagination, error cases, or response structure are disclosed, and with annotations present the added value is moderate.

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 a single, compact sentence that fronts the main purpose and the optional flag. There is no verbosity, and the extra phrase 'worth showing before the creator shares it' is brief and adds contextual intent without waste.

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 read-only tool with two parameters (one required), no output schema, and robust annotations, the description provides enough to call it correctly. It explains what it returns and the meaning of the optional flag. No critical gaps remain for invocation.

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 50% (only 'items' has a description). The description clarifies the semantics of 'items' (switching to product list), adding some value beyond the schema. It does not explain 'id' beyond its name, but its purpose is evident from the tool name. Given low coverage, the description partially compensates but not fully.

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 states the specific resource (one discount code) and the two possible outputs (detail or covered products via the 'items' flag). It distinguishes from sibling tools like split_list_discount_codes by emphasizing singular access and explicitly mentioning the optional behavior.

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 use for retrieving a single code's detail or its product list, contrasted with listing tools. It offers a contextual hint ('worth showing before the creator shares it') but does not explicitly name alternatives or conditions for when not to use it. Lacks explicit routing, but the singular framing is sufficient for clarity.

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