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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description nevertheless adds useful behavior: normalization to hourly rate and simple APR %, a hard coverage ceiling of 6 venues, and the fact that access is free (no auth/key needed). It doesn't say what happens when a coin isn't listed on a given venue.

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?

A single front-loaded sentence that states the resource, scope, venue set, and output normalization with no 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 one-parameter read tool with no output schema, the description supplies what an agent needs: what is returned (hourly rate and APR), from where (named venues), and at what cost. Only the partial-coverage case (coin missing on some venues) is left unaddressed.

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?

Only one parameter and schema coverage is 100%, so the schema already fully documents 'coin'. The description reinforces the single-coin scope ('for one coin') but adds no ticker format or case-sensitivity detail beyond the schema's own example list.

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?

Names a specific resource (live perpetual futures funding rates) for a single coin, with the venue set and normalization spelled out. It does not explicitly contrast itself with the siblings get_funding_history (past data) or find_funding_arbitrage (cross-venue opportunity scanning), so the distinction must be inferred from the word 'live'.

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?

Usage is implied by 'Live ... for one coin' — a point-in-time snapshot for a single ticker — but there is no explicit statement of when to prefer this over get_funding_history or find_funding_arbitrage, and no exclusions or prerequisites.

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