compare_methods

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

With no annotations, the description carries full burden. It discloses that results include total deltas and the single AY with largest divergence, and mentions possible license failure. It does not detail error handling for invalid inputs, but overall provides good behavioral context.

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?

The description is front-loaded with purpose and usage guidance, followed by parameter list and return values. It is well-structured but slightly lengthy with the detailed return fields. Good balance of completeness and conciseness.

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 5 parameters with 2 required and an output schema present, the description covers purpose, usage, parameter references, and return fields including error case. Reliance on cross-reference for parameter details is a minor gap, but overall contextually complete.

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 description must compensate. The description references 'As in compute_chain_ladder' for triangle, selected_factors, tail, excluded, and explains a_priori_ultimates. This adds meaning but relies on cross-reference, which is minimal adequate.

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 runs chain ladder and Bornhuetter-Ferguson on the same triangle and returns a side-by-side comparison. It distinguishes itself from sibling tools that compute individual methods.

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?

The description provides clear context: 'The canonical second opinion — when both methods agree, the reserve is defensible; when they diverge, the divergence is the finding.' It also notes the Pro tier, implying licensing requirements. However, it does not explicitly state when not to use this tool or suggest alternatives.

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