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

No annotations are provided, so the description must carry the full behavioral burden. It discloses 'without charging,' which is useful, but it does not mention whether the operation is read-only overall, what happens with an invalid pass, or any authentication requirements. For a status tool with zero annotation support, this is insufficient.

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 sentence, which is concise and front-loaded. However, its brevity comes at the cost of clarity and completeness, so it earns a 4 rather than a 5.

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?

With one parameter and no output schema, the description should still explain what the tool returns or what 'status' entails. It does not mention the response format, error handling, or whether the pass must be valid. This is a significant gap for an agent trying to interpret the result.

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 100%, and the schema itself provides a detailed description of the api_pass parameter including format and a caution to save before buying. The tool description adds no additional meaning about the parameter, so the baseline score of 3 applies.

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 'Monthly data package and private purchase status, without charging' indicates a status-check resource but lacks a strong verb like 'check' or 'retrieve'. It does not distinguish itself from siblings such as api_access_buy (purchase) or api_index (index), so an agent cannot confidently select it without additional inference.

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?

No guidance is given on when to use this tool versus alternatives. It does not mention that this is for checking an existing pass, nor that api_access_buy should be used for purchasing. The absence of any contextual routing leaves the agent to guess.

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