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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds behavioral specifics: data is 60s fresh, up to 5 symbols per call, and each symbol carries plain-language notes. It also discloses the interpretive regimes (OI×price) which go beyond a simple data fetch. No contradiction with annotations.

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 detailed but efficient, with the core purpose front-loaded ('Funding rate, open interest and positioning'). Every sentence contributes context about metrics, regimes, or freshness. It is a bit dense but avoids fluff; only minor over-explanation in the regime listing.

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?

The output schema exists (per context signals), so return values are covered. The description explains limits, freshness, and the meaning of the data, which is sufficient for a read-only tool. It does not mention authentication or prerequisites, but annotations (openWorldHint, readOnlyHint) and the output schema likely cover the remaining context. Complete enough for an agent to invoke 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 coverage is 100%, and the schema explains the 'symbols' parameter with an example and the note about bare base assets. The description does not add meaning beyond what the schema provides; it merely restates the limit of 5 symbols. Baseline 3 is appropriate since the schema fully documents the parameter.

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 provides funding rate, open interest, and positioning for Binance USDⓈ-M perpetual futures. It specifies the exact metrics and explicitly frames these as 'derivatives questions candles cannot answer,' distinguishing it from price/candle tools. The verb 'get' and resource are unambiguous.

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 implies use when needing derivatives-specific data (funding, OI, positioning) rather than price action, and says 'candles cannot answer' to suggest alternative tools like get_candles for other needs. It does not explicitly name alternative tools or state when not to use it, but the context is clear enough for an agent to route correctly.

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