Coffee Company MCP Server

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

With no annotations provided, the description carries full burden. It discloses the HTTP API endpoint (POST /coupon/detail) and explains coupon status codes (4=unused, 10=used, 20=expired, 30=voided), which adds useful behavioral context. However, it doesn't mention authentication requirements, rate limits, error conditions, or whether this is a read-only operation (though '查询' implies querying).

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 appropriately sized and front-loaded: the first sentence states the core purpose and returned fields. The API endpoint and status code explanations are relevant additions. The parameter documentation is concise with an example. No wasted sentences, though the structure could be slightly more polished (e.g., separating status codes into a bullet list).

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 has an output schema (which handles return values), no annotations, and a simple single-parameter input, the description is reasonably complete. It explains what the tool does, documents the parameter with an example, provides status code mappings, and mentions the API endpoint. For a read-oriented detail tool, this covers most essential context, though it could benefit from mentioning authentication or error handling.

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 has 0% description coverage, but the description compensates well. It explains the single parameter 'coupon_code' with a clear example ('如 "CC20260301A001"') and specifies it's required. Since there's only one parameter and the description fully documents it, this exceeds the baseline of 3 for high schema coverage scenarios.

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 tool's purpose: '查询单张券码的详细信息' (query detailed information of a single coupon code) and lists specific fields returned (status, face value, validity period, redemption count). It distinguishes from sibling 'coupon_query' by focusing on a single coupon rather than a list/query operation. However, it doesn't explicitly contrast with 'equity_detail' or other detail tools.

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 usage context by specifying it's for querying '单张券码' (single coupon code), suggesting it should be used when you have a specific coupon code to examine. However, it doesn't provide explicit guidance on when to use this versus 'coupon_query' (likely for bulk/search operations) or other sibling tools, nor does it mention prerequisites or exclusions.

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