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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds meaningful behavioral context beyond annotations: source (Polymarket), returned fields, pricing ($0.005 USDC per call via x402 or prepaid credits), and free-trial availability.

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 front-loaded with the core purpose and operating modes, then covers return contents, audience, and price compactly. Every sentence contributes something useful, and there is no redundant explanation.

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 an output schema present, the description need not explain return values, but it still gives a useful preview of returned fields. Combined with complete parameter descriptions and annotations, it is fully sufficient for an agent to select and invoke the tool correctly.

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 description coverage is 100%, so all four parameters are already documented in the schema. The description repeats the q search examples and the omit-q behavior, but adds little semantic detail beyond what the schema provides. The baseline 3 is appropriate when the schema carries the parameter 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 states a specific resource and source: prediction-market odds from Polymarket. It immediately clarifies the two operating modes (search a topic via q, or omit q for trending markets) and identifies the data returned. This is enough for an agent to distinguish it from generic search, news, or token-price siblings.

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?

It gives clear context for use: search any topic or omit q for the most-traded markets now, and it names research, forecasting, and trading agents. However, it does not explicitly compare itself to a sibling alternative or state when another tool should be used instead.

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