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

With no annotations, the description carries the full burden and does well: it discloses the paid model, the exact cost and chain, that no account or API key is needed, and the underlying endpoint. It does not cover failure modes, rate limits, or staleness of odds, which keeps it short of 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?

Three compact sentences, front-loaded with the paid flag and the core capability, followed by cost and access details. Every clause carries information: fields returned, price, chain, auth, endpoint.

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?

No output schema exists, but the description compensates by enumerating the returned fields (odds per outcome, volume, liquidity, end date, link), and the access and payment model are covered. The only gap is behavioral edge cases such as what an empty result or payment failure looks like.

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% for the single optional 'limit' parameter, so the baseline of 3 applies. The description mentions 24h-volume ordering, which implies the ordering of returned rows but adds no meaning beyond what the schema's 'Markets, 1-50 (default 10)' already states.

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 names a specific resource (live Polymarket odds for 'crypto' markets) and a specific ordering (24h volume), and enumerates exactly what the agent gets back. An agent can distinguish it from buy_pm_bitcoin or buy_pm_ethereum because the scope here is the whole crypto category rather than one asset.

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?

Usage is implied by the topic ('crypto' markets) and the price signal ($0.10 USDC), but there is no explicit statement of when to pick this over buy_polymarket or the asset-specific buy_pm_* siblings, and no exclusions. The agent must infer that this is the broad-category query.

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