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

Annotations already declare read-only, idempotent, and non-destructive behavior. The description adds useful behavioral context by noting data is 60 seconds fresh and that each symbol carries plain-language notes that should be quoted, giving the agent clear expectations about output style and data timeliness.

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 description is somewhat dense with rhetorical questions and parentheticals, but it remains purposeful and front-loaded with the core resource and data types. The repetition of 'Up to 5 symbols per call' is slightly redundant with the schema, but the overall structure is efficient and readable.

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?

Given the single-parameter schema, an output schema, and rich annotations, the description is complete enough for correct invocation. It covers what data is returned, how the parameter behaves, output note guidance, freshness, and usage limits, leaving no critical gap for the agent.

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 schema description fully explains the single `symbols` parameter, including the array limit of 1–5, concrete examples like 'BTCUSDT' and 'ETHUSDT', and the rule that a bare base asset like 'BTC' is interpreted as its USDT perpetual. This exceeds basic parameter documentation.

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 clearly states the tool returns funding rate, open interest, and positioning data for Binance USDⓈ-M perpetual futures, and explicitly frames it as 'the derivatives questions candles cannot answer.' This makes the resource and data scope unambiguous and distinguishes it from price/candle-focused sibling tools.

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?

The description gives concrete use cases—checking whether funding is high, whether open interest is building/unwinding, and how accounts lean—and notes the 5-symbol limit and 60-second freshness. It does not explicitly name alternative tools beyond 'candles,' but the use-case framing is strong enough to guide selection.

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