get_card_performance

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 discloses premium gating and API key requirement, which adds transparency. However, it does not describe what happens on authentication failure, how P&L is calculated, or the response format. More details would improve transparency.

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 extremely concise with three sentences: purpose, defaults, and constraints. It is front-loaded with the core action, and every sentence adds value. There is no redundancy or fluff.

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 simplicity of the tool (2 optional parameters), the description covers the essential usage context. However, due to the lack of an output schema and annotations, the agent lacks information about the expected response format and any possible errors. The description is adequate for a straightforward retrieval but not fully complete.

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 compensates for 0% schema coverage by stating defaults ('Default: best, top 10'), which indirectly explains the 'type' and 'limit' parameters. However, it does not explicitly define each parameter's meaning or behavior beyond defaults. The enum values are self-explanatory from the description, but the 'limit' parameter lacks full documentation.

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 what the tool does: 'Get the user's best- or worst-performing cards by P&L'. It specifies the verb 'get', the resource 'cards by P&L', and provides additional detail on default behavior ('Default: best, top 10'), distinguishing it from sibling tools which do not offer P&L performance data.

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 mentions that the tool is 'Premium-gated' and 'Requires IWMM_API_KEY', which provides necessary context for usage prerequisites. However, it does not explicitly state when to use this tool versus alternatives or when not to use it. The usage is implied but lacks clear guidance on exclusion conditions.

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