payping_get_couponRetrieve a PayPing coupon by its code to view its amount, expiry, max uses, number of buyers, and their total spend.
One coupon by code: amount, expiry, max uses, number of buyers and their total spend.
| Name | Required | Description | Default |
|---|---|---|---|
| code | Yes |
Changes observed during successful MCP inspections.
v0.2.0Input schema / properties / code / titleRemoved value: -"Code"Input schema / titleRemoved value: -"payping_get_couponArguments"Output schema / (root)Previous value: -{
- "additionalProperties": true,
- "title": "payping_get_couponDictOutput",
- "type": "object"
-}New value: +nullv0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, non-destructive and openWorld, so the safety profile is covered. The description adds genuine value by disclosing the returned data (amount, expiry, max uses, buyer count and total spend), which no output schema provides. It stops short of error behavior (e.g. unknown code) or auth requirements.
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 dense sentence, front-loaded with the resource and lookup key, then the return fields. Every clause earns its place, though the field list is a touch listy rather than explanatory.
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 one-parameter lookup with an output-free schema, the description covers what an agent needs: the resource, the lookup key, and the shape of the return. It omits only edge-case behavior such as missing/invalid codes, which is a minor gap for a read-only tool.
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 0% and there is no description on the 'code' property, so the description must carry the burden. 'One coupon by code' implicitly informs the agent that the sole parameter is a coupon code identifier, but it adds no format, case-sensitivity, or length guidance beyond that.
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 resource and scope: 'One coupon by code', which cleanly implies a single-item retrieval and implicitly contrasts with payping_list_coupons. It also enumerates the returned fields, so an agent knows exactly what it gets. The only gap is that it never names the sibling alternative, but the resource+cardinality 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?
The description gives no when-to-use guidance, no when-not-to-use, and does not point to payping_list_coupons or payping_create_coupon as alternatives. The 'by code' phrasing weakly implies the lookup key, but there is no explicit context for choosing this tool over its siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.