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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds real context beyond them: it is read-only analytics, not financial advice, it is a limited free tier, and it discloses which signals are withheld from the preview and available only on paid routes. It does not explain the idempotentHint=false behavior (live-updating data).

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 purpose and outputs are front-loaded in the first sentence, followed by tier information. It is dense but every clause carries information; the paid-route enumeration is somewhat promotional but genuinely helps routing decisions.

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?

With no output schema, the description carries the burden of explaining return values and does so (classification, venues, confidence), plus tier limits. Complete enough to call correctly; it could be slightly clearer on the shape/format of the response.

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?

There is a single required parameter with 100% schema description coverage, including accepted formats (BTC, BTC-PERP, SOLUSDT). The description adds no parameter-level meaning beyond the schema, so the baseline of 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 ('cross-venue perpetual futures positioning read for an asset') and names the exact data sources (Hyperliquid, dYdX v4, Paradex, Aevo). It also enumerates the returned classification (crowded long → crowded short), listed venues, and confidence, so an agent knows precisely what it produces without opening a schema.

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 the 'free preview tier' and routes the agent to the paid x402 routes for per-venue funding/OI (/v1/lite), premium/history/carry (/v1/full), and funding extremes/spreads (/v1/scan). This is clear context for choosing this tool versus the richer variants, though it gives no explicit exclusion (e.g. when not to use it).

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