KLane Perp Funding Rates

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

Annotations already establish readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely useful context beyond that: the free-tier cap of 3 results, the 100-result ceiling with a key, and that the key is passed via the x-api-key header. Remaining gap is latency/caching behavior, which is minor for a screening query.

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?

Three dense clauses with zero filler, front-loaded with the output definition before tiering and parameter constraints. Every sentence carries information the agent needs to decide and call correctly.

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?

With no output schema, the description compensates by defining the returned fields (long venue, short venue, APR spread) and result caps. Combined with a fully documented schema and read-only annotations, an agent has enough to invoke it correctly; only error behavior for a missing/invalid key is unspecified.

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 description coverage is 100%, so baseline is 3. The description adds value by tying parameters to access tiers: limit is capped at 3 without a key, and min_oi_usd requires a key, which the schema alone does not convey. min_apr's default of 10 is only in the schema, not repeated here, which is fine.

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?

States a specific computed resource: for each coin on 2+ venues, the lowest-funding (long) venue vs highest-funding (short) venue and the APR spread. That is far more than a restatement of the name and makes the calculation unambiguous. It doesn't explicitly contrast with get_funding_rates or get_funding_history, but the arbitrage framing makes the distinction inferable.

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 through the tiering: free returns top 3, a Pro/trial key unlocks up to 100 results and the min_oi_usd filter. That tells the agent when the tool will be limited, but it never says when to prefer this over the sibling funding tools (raw rates, history).

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

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

Adds real context beyond the readOnly/openWorld annotations: the x-api-key requirement (Pro key or 3-day trial), the Bybit source being conditional on reachability, and the 30-day hard limit. It does not contradict the annotations. Missing only return shape or rate-limit behavior, but the auth/fallback disclosure is above average.

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?

Two sentences, front-loaded with what the tool returns, with prerequisites second. Dense but every clause adds useful information; the parenthetical source list is slightly crowded but earns its place.

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 two-parameter, read-only tool with no output schema, the description covers sources, timeframe bounds, auth requirement, and output metric (average APR). The remaining gap is the format of the required 'coin' argument and the shape of returned data, which keeps it from a 5.

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 50%: 'days' is documented in the schema as 1-30 default 7, and the description's 'last N days (max 30)' only echoes that. The required 'coin' parameter has no schema description and the description gives no format hint (ticker symbol vs pair), so it does not fully compensate for the gap. Baseline 3 applies.

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?

States a specific verb and resource ('Hourly funding history for a coin'), names the venues (Hyperliquid, Bybit) and adds the APR output. It implicitly differs from get_funding_rates (current rates) and find_funding_arbitrage, but never explicitly distinguishes itself from those siblings, so it falls short of a 5.

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 only implied by the word 'history' and the 30-day cap; there is no explicit 'use this instead of get_funding_rates when…' guidance and no exclusions. The auth prerequisite is stated, which is the main contextual hint, but routing between siblings is left to inference.

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

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.