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 meaningful context beyond annotations: it is a free preview tier, paid routes extend the same data, and it is explicitly read-only analytics and not financial advice, though it does not mention auth, rate limits, or freshness.

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 positioning read is front-loaded in the first sentence, and the free-vs-paid distinction follows logically. It is somewhat dense with endpoint paths and parenthetical funding details, but the information is useful rather than repetitive.

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?

There is no output schema, so the description carries the full burden of explaining return values, and it does list the classification, supporting venues, and confidence score. It also explains the free tier and what paid tiers add, making the definition complete enough for an agent to call it correctly.

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% and the single symbol parameter already documents accepted formats such as BTC, BTC-PERP, ETH-USD, and SOLUSDT. The description adds no further parameter semantics, so the baseline 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?

The description states a specific verb and resource: a cross-venue perpetual futures positioning read for an asset, derived from funding rates on named venues. It also names the exact output categories (crowded long / long bias / neutral / short bias / crowded short), venues, and confidence, so an agent can immediately tell what the tool produces.

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 clearly frames this as the free preview tier and explains that paid x402 routes add richer data such as median funding, per-venue funding, open interest, history, carry, and universe scans. That gives useful routing context, though it stops short of explicit when-to-use/when-not-to-use guidance or prerequisites.

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