Accrued interest

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

The description states 'Deterministic' implying no side effects, but for a computation tool, that is baseline. It does not disclose edge cases, error handling, or behavior when inputs are invalid (e.g., negative notional, reversed dates). With no annotations, the description carries the full burden and falls short.

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 with no wasted words. The first sentence states the core purpose, the second adds format details. Highly efficient.

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?

The description covers the input and formula but does not describe the return value (presumably a number, likely in the same currency as notional). For a tool without an output schema, this omission reduces completeness.

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?

With 83% schema description coverage, the schema already documents parameters. The description adds value by clarifying the formula (notional * rate * day-count fraction) and emphasizing that rate is a decimal, which reinforces the schema. This goes beyond the baseline of 3.

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 clearly states the tool computes exact simple accrued interest using notional, rate, and day-count fraction between two dates. It distinguishes from sibling tools (day_count_fraction, list_conventions) by focusing on the full interest calculation rather than just the fraction or conventions.

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?

No guidance on when to use this tool vs alternatives. It does not mention that day_count_fraction is for obtaining the fraction alone, nor does it specify any prerequisites or when not to use it.

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