get_coupon

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool retrieves a coupon but doesn't mention whether this is a read-only operation, what permissions are required, error handling (e.g., for invalid IDs), or response format. For a retrieval tool with zero annotation coverage, this leaves significant behavioral gaps.

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, clear sentence with zero wasted words. It front-loads the essential information ('Get a single coupon') and efficiently specifies the method ('by ID'). Every part of the sentence contributes directly to understanding the tool's function.

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 tool's low complexity (single parameter, retrieval operation) and the presence of an output schema (which handles return values), the description is minimally adequate. However, with no annotations and 0% schema description coverage, it lacks context on permissions, errors, or behavioral nuances. It meets basic needs but leaves room for improvement in transparency.

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 description mentions 'by ID', which aligns with the 'coupon_id' parameter in the schema. However, schema description coverage is 0%, so the schema provides no parameter descriptions. The description adds minimal semantic context (it's an ID) but doesn't explain format, constraints, or examples. With 1 parameter and low schema coverage, this is a baseline score.

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 clearly states the action ('Get') and resource ('a single coupon by ID'), making the purpose unambiguous. It distinguishes this tool from sibling tools like 'list_coupons' by specifying retrieval of a single item rather than a collection. However, it doesn't explicitly differentiate from other 'get_' tools like 'get_customer' or 'get_product' beyond the resource type.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention when to prefer 'get_coupon' over 'list_coupons' (e.g., when you have a specific coupon ID), nor does it reference other sibling tools like 'deactivate_coupon' for related operations. Usage is implied by the name but not explicitly stated.

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