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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety profile is covered. The description adds genuinely useful behavioral context — a $0.03 USDC x402 payment on Base per call — but says nothing about pagination, date-range limits, or result shape.

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 core sentence is efficient and front-loaded, but the pricing is stated twice ('$0.03 USDC x402 Base' and '[x402: 0.03 USDC per call on Base]'), which is redundant and wastes space.

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 read-only query tool with no output schema and a single free-form param, the description covers the operation and cost but omits return-format expectations and any usage guidance, leaving the agent to construct the JSON payload by guesswork.

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%, but the single 'input' param is documented only as generic 'product parameters (JSON or text)' with a limit example. The description hints at available filters and per-wallet aggregation but gives no parameter names or formats, so it does not compensate for the vague schema text. Baseline 3 applies.

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 and resource (historical Polymarket trade query) and mentions the two facets of the operation: filters and per-wallet aggregation. It does not explicitly differentiate itself from the sibling polymarket_markets tool, so it falls short of a 5.

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, when-not-to-use, or alternative-tool guidance is given. The agent has to infer from the name that this is the trades endpoint versus polymarket_markets; nothing in the description routes it.

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