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

With no annotations, the description carries the full burden and does disclose real behavior: it is free, returns only the top 3 by 24h volume, and the richer dataset is gated behind a paid x402 call. It also names the return signals (live odds, 1h/24h change, volume). It stops short of covering auth, rate limits, or empty-result behavior.

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?

Two dense sentences with zero filler: the free/limited scope and return fields come first, and the paid upsell is a brief trailing pointer. Nothing could be cut without losing routing information.

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 one-parameter tool with no output schema and no annotations, the description covers the essentials: result count, ranking basis, returned fields, and the paid alternative. Only the differentiation from polymarket_movers_preview is missing.

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% and the single 'q' param is already documented, so the baseline is 3. The description adds value by showing concrete example values ('bitcoin', 'election') that clarify what kind of keyword filters work, pushing it above baseline.

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 with scope: 'top 3 open Polymarket markets by 24h volume', plus the returned fields. It names the paid sibling polypulse_paid_endpoints but never distinguishes itself from the other sibling polymarket_movers_preview, so an agent must infer the split.

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?

Explicitly frames itself as a free preview and routes to polypulse_paid_endpoints for the full up-to-50 list, giving a clear use/alternative condition. It does not, however, say when to prefer this over polymarket_movers_preview.

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