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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, so the safety profile is covered. The description adds real context annotations don't: per-market vs single-coin scope, the N-day window, and pricing ($0.002/call or Carry key). It does not describe output shape or latency, so not a 5.

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?

Dense but front-loaded: metric list first, then cost, then the routing hint. Terse telegraphese phrasing costs a little readability but every clause carries information.

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?

No output schema exists, and the description enumerates the returned quantities (floor/premium/negative/zero percentages, current regime, dex counts), which is sufficient for an agent to know what it gets. Missing only explicit default value for days.

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%: coin is documented in the schema, days carries only min/max bounds. The description supplies meaning for days ('over N days') and clarifies the coin scope, but adds no format or default guidance beyond that, matching the baseline for partial coverage.

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-less but precise analytical product: percent of hours at the 10.95%/yr floor, in premium/negative/zero over N days, regime now, counts by dex, per market or single coin. It also names the sibling (carry_funding_matrix) it differs from, so an agent can distinguish it without opening either schema.

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?

Explicit when-to-use clause ('how often a market sits at the funding floor vs premium') paired with an explicit alternative for a different need ('for current levels use carry_funding_matrix'). No inference required.

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