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

Annotations already declare readOnlyHint, openWorldHint and destructiveHint, so safety is covered. The description adds genuinely useful context beyond them: the call costs $0.003 USDC on Base and output is pre-sanitized via CanaryGuard, which is important for an agent deciding whether to spend. Return format is not described, but an output schema exists to carry that.

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?

A single tight sentence that front-loads the resource and scope, then appends the cost/sanitization caveat. Nothing is padded, though the trailing 'Price' clause reads as a slightly separate concern rather than part of the core description.

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 no-arg, read-only data fetch with an output schema covering return values, the description supplies what an agent needs: what it returns, freshness, cost, and sanitization. It is complete enough to invoke correctly, with only sibling routing left implicit.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate. The baseline for a parameterless tool is 4, and the description introduces no misleading parameter expectations.

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 (Polymarket whale orderbook imbalances and CLOB skew) with explicit scope ('Top 10 ... right now'), so an agent can tell it apart from the odds/divergence/macro siblings. It stops short of naming which sibling to use instead, so it falls below the top band.

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?

There is no explicit when-to-use or when-not-to-use guidance, nor any reference to the alternative Polymarket tools. 'Right now' only implies a real-time, point-in-time read; the agent must infer when this beats polymarket_alpha_divergence or polymarket_crypto_odds.

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