Cross-Venue Funding Spread for a Ticker

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, openWorldHint=true, so the tool's safety profile is clear. The description adds the cost ($0.001 USDC per call) and states it returns a snapshot with specific components (spread in basis points). It does not contradict annotations, and provides valuable additional behavioral context beyond what annotations cover.

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 extremely concise: two sentences plus a cost note. It immediately states the main function, then details the output components. Every sentence adds value with no redundancy. Front-loaded with the core purpose.

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 simple snapshot tool with one parameter and no output schema, the description covers purpose, output components, cost, and usage context (arbitrage). Minor gaps include lack of error handling for invalid tickers or network issues, but these are not critical given the tool's simplicity and the schema's validation. Overall, it provides sufficient context for an agent to use 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?

The only parameter 'ticker' is fully covered in the input schema with a description, pattern, and example. The description does not add any further meaning about the parameter beyond what the schema provides. Schema coverage is 100%, so baseline 3 is appropriate.

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 uses specific verbs ('Returns the cross-venue funding-rate spread snapshot') and identifies the resource (base ticker). It clearly explains that it identifies long-side and short-side venues and reports the spread in basis points, which distinguishes it from siblings like usenami_funding_current (which likely returns a single venue's rate). The arbitrage context further clarifies its unique role.

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 usage for funding-rate arbitrage by mentioning 'directional edge', but it does not explicitly state when to use this tool vs. alternatives (e.g., usenami_funding_current). There are no 'when-not-to-use' statements or comparisons to sibling tools. The usage context is implied but not formally guided.

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