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

With no annotations, the description carries the behavioral disclosure burden. It clearly describes what the tool returns, the fields in the tape, the derived statistics, and the cross-asset support. It does not mention pagination, limits, or output envelope details, but for a read-only market-data tool the conveyed behavior is substantial.

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 efficiently written in three sentences, front-loading the core purpose and then adding asset-class scope and sibling differentiation. The opening repeats the tool name and 'a signal actually uses' is slightly filler, but there is minimal waste.

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?

The description explains the output well but leaves invocation details unresolved: it does not specify how id, symbol, or instrument select the market, what hours and limit control, or whether output is raw fills plus an aggregate object. Given five parameters, no required fields, and no output schema, more operational detail would be needed for fully 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 description coverage is 100%, so the baseline is 3 even though the description itself adds no parameter detail. However, the schema descriptions like 'Id to process', 'Hours to process', and 'Symbol to process' are tautological and do not clarify how the five parameters interact or which one selects the market.

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 action: the recent trade tape for one Polymarket Perps market, including fills with side, price, size, and timestamp, plus derived flow statistics. It explicitly distances itself from x402-polyperp-book, making the tool's identity unambiguous.

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 names the alternative tool, x402-polyperp-book, and gives a clear rule: use the book for resting liquidity and this tool for what actually executed. This is explicit selection guidance rather than vague implication.

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