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

Annotations only cover read-only/idempotent/open-world safety; the description goes far beyond them with caching behavior (1 hour, <5ms cache hit), the pricing model ($0.015/call, 5 free calls per agent_id, failed calls never charged), and the non-fatal payment-required quote response with top-up mechanics. This is exactly the operational context an agent needs before invoking a metered endpoint.

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?

Purpose is front-loaded and the WHEN TO USE / WHEN NOT TO USE / PARAMETER INTERACTIONS structure is scannable. However, the free-call rule is stated twice (in PARAMETER INTERACTIONS and again in the Pricing sentence) and the payment flow is verbose, costing some efficiency.

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 does not need to explain return values, and it covers everything else an agent needs: authentication path, trial vs paid behavior, cost, caching, and retry-after-payment. Nothing material is missing for correct invocation.

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%, so the baseline is 3; the description nonetheless adds workflow meaning beyond the schema by explaining that agent_id and tx_hash should be omitted during the 5 free trial calls and supplied afterward for paid execution. It slightly restates the agd_pass_/tx_hash semantics already present in the schema, capping it below 5.

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?

States a specific verb (fetches) and a precise resource set: live Polymarket orderbooks, implied Yes/No probabilities, volume, and whale sentiment for macro/crypto/AI events. That is clearly distinguishable from the only sibling, get_agent_wallet_status, which is about quota/balance rather than market 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?

Explicit WHEN TO USE and WHEN NOT TO USE sections, including the exact sibling to use for quota checks ('use get_agent_wallet_status to check your remaining free trial quota or prepaid balance'). It also names the domain boundary ('unrelated domains or binary media'), leaving little to inference.

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