calculate_cagr

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

Without annotations, the description carries full burden. It only mentions the formula, not edge cases (e.g., zero division with negative values), error handling, or whether it returns a decimal or percentage. The behavioral context is minimal.

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 essential information, front-loaded with purpose. However, the second sentence repeats the formula which could be inferred from the name, making it slightly redundant. Still efficient overall.

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?

Given no annotations and low schema coverage, the description omits important context like return format, error conditions, and prerequisites. The existence of an output schema partially mitigates the lack of return documentation, but usage guidance is missing.

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 0%, so the description must compensate. It names start_value, end_value, and years in the formula but does not define their meaning, valid ranges, or examples. The description adds only partial value beyond the schema property titles.

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 it calculates CAGR, provides the formula, and identifies it as a standard measure for investment returns. It effectively differentiates from sibling tools that handle other financial calculations.

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 explicit guidance on when to use CAGR vs other tools like calculate_future_value or compare_loans. The description implies it's for investment returns but lacks when-not-to-use or alternative recommendations.

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