Rotating 5% windows

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

No annotations exist, so the description carries full burden. It does not explicitly state this is a read-only operation, mention authentication prerequisites, describe pagination or rate limits, or clarify outcomes for invalid card IDs. Phrases like 'live and upcoming' hint at temporal scope but not behavioral traits. This is a significant gap for a tool without annotation support.

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 efficient sentence, front-loading the core resource and examples, with the optional parameter placed at the end. No wasted words, no repetition of schema details, and it fits naturally for a tool of this scope.

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 a single optional parameter, no output schema, and no annotations, the description sufficiently conveys what the tool returns (live/upcoming rotating windows and permanent benefits) and how to narrow results. It does not detail response structure or edge cases, but for a straightforward lookup tool, the essentials are covered.

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?

With 0% schema description coverage, the description compensates by explaining card_id is an 'optional' 'filter'. This adds semantics beyond the bare schema (type: string). However, it does not clarify the ID's format, how to obtain it, or its relationship to the returned data, leaving partial ambiguity.

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 provides live and upcoming rotating-category windows and permanent merchant benefits, with concrete examples (Freedom Flex, Discover it, Citi Dividend). This distinguishes it from siblings like lookup_merchant (merchant-specific) and best_card (recommendation). However, it lacks an explicit verb (e.g., 'list' or 'retrieve'), relying on inference that it returns this 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?

No when-to-use or when-not-to-use guidance is provided. The description mentions optional filtering by card ID but does not contrast this tool with alternatives such as best_card or search_cards, nor does it indicate scenarios where one would choose this over others. The usage context is only implied by the resource name.

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