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

With no annotations, the description carries the full burden and does substantial work: it discloses the exact output fields (per-venue annualized funding, OI USD, 24h volume, max-min spread with short/long venue, mean APR, totals, coverage) and a payment requirement of $0.008 USDC via x402. What remains undisclosed is rate limiting, latency, and behavior when a coin is missing from some venues, though the coverage field partly mitigates the last point.

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 structure is well front-loaded: trigger first, then Input, Output, Example and price, so an agent can stop reading once it has what it needs. The final clause crams an example and the x402 price into one unpunctuated line, which is slightly awkward but not wasteful.

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 6-parameter, no-output-schema tool, the description covers trigger, inputs, return shape and cost. Because there is no output schema, describing the returned row fields and the coverage field is exactly the missing piece an agent needs, and it is supplied here.

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 every parameter is already documented in structured form and the baseline is 3. The description's parameter list ('sort, order, limit (1-50), venues, min_venues, min_oi_usd') largely restates the schema names, adding only a worked example query string rather than new semantics.

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 verb and resource ('scans every perp listed on Hyperliquid, dYdX v4, GMX v2, Lighter and Paradex') and states the analytical goal (funding arbitrage or crowding). The cross-venue scope is explicit, which clearly separates it from single-venue siblings like hl_funding_screener and crypto_perp_funding.

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 opens with an explicit trigger ('Use when an agent scans every perp ... for funding arbitrage or crowding'), giving a clear condition for selection. It stops short of naming the alternative tools (hl_funding_screener, crypto_perp_funding) or saying when not to use it, so routing between the single-venue and cross-venue tools is left to inference.

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