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

Annotations already declare readOnlyHint, non-destructive, and closed-world, so the safety profile is covered. The description adds the return field names, which is useful given no output schema, but says nothing about unit conventions, sign of requiredMovePct, or how holding period interacts with discrete funding periods.

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 short sentences, purpose front-loaded, examples then return keys. Efficient, though the quoted example questions are slightly verbose relative to the rest.

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 an 8-parameter compute tool with no output schema, the description supplies return field names and triggering intent, and the schema documents the rest. It is nearly complete, with only units/sign conventions for the returned values left implicit.

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 88% and contractType explicitly documents denomination behavior, so the schema carries the load. The description adds no parameter-level detail beyond 'holding period', so the 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 first sentence names a specific computation (price move needed to cover funding + fees over a holding period), which an agent can distinguish from generic 'breakeven' siblings. It does not explicitly differentiate from run_breakeven_planning, run_funding_cost, or run_compound_funding, which are the closest neighbors.

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?

Two concrete example user phrasings are given, which map cleanly to invocation triggers. There are no explicit exclusions or named alternatives (e.g. use run_funding_cost instead when only the cost figure is wanted), so it falls short of a 5.

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