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

With no annotations, the description carries the full burden and does disclose key operational behavior: it is paid, costs $0.005 USDC on Base, requires no account or API key, and lists the returned fields. It does not cover rate limits, payment failure behavior, or whether repeated calls incur repeat charges, which prevents a 5.

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 most important facts: paid, live Polymarket odds, active markets sorted by volume. It then efficiently covers return fields, optional filtering, cost, authentication, and the endpoint URL without unnecessary repetition.

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?

For a paid data-fetch tool with no annotations or output schema, the description is largely complete: it explains the data returned, cost, authentication requirements, filtering, and the endpoint URL. It lacks detail on payment mechanics, rate limits, and error behavior, which would be helpful for an agent invoking a paid API.

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 both the q and limit parameters are already fully documented in the schema. The description only restates that there is an optional keyword filter and does not add syntax, formatting, or behavioral meaning beyond the schema.

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 scope: live Polymarket prediction-market odds for active markets sorted by 24h volume, including the return fields. This clearly distinguishes it from sibling tools like buy_crypto_price, buy_hn, and buy_search without needing to open the schema.

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 through the named data source and notes that it is paid, but it does not explicitly say when to use this tool versus its siblings or when not to use it. An agent can infer that it is for Polymarket market data, but no alternatives or exclusions are provided.

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