Perp funding & open interest

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

With no annotations, the description carries the full burden. It discloses it reads data and includes cost details (PAID TOOL: up to $0.01), which is useful. However, it does not mention return format, latency, limitations, or any other behavioral traits, leaving some ambiguity for a tool with no output schema.

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 concise and front-loaded: the first sentence states the core function, the second adds context, and the third discloses the paid tool cost. Every sentence serves a distinct purpose, with no redundancy or filler.

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 single-parameter read tool with no output schema, the description provides adequate context: what it reads, scope (across exchanges), and cost. However, it lacks details like whether data is real-time/historical, which exchanges are covered, or response structure, so it is not fully comprehensive.

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 only parameter, symbol, has a clear schema description ('Asset symbol (BTC, ETH, SOL...).') providing 100% coverage. The tool description adds no additional parameter semantics, so it meets the baseline for schema-covered parameters without enhancing understanding.

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 identifies the tool as providing funding rates and open interest for perpetuals across exchanges, and adds 'Reads leverage positioning' which conveys the analytical use. This is distinct from sibling tools like token_price (spot) or defi_yields (yield), so it effectively differentiates itself.

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 implies it is used for leverage/sentiment analysis ('Reads leverage positioning') but does not explicitly state when to choose this over alternatives like token_price or wallet_risk. No exclusion criteria or alternative tool references are given, so usage guidance is only implied.

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