compare_two

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

With no annotations provided, the description carries the behavioral burden. It discloses the exact outputs (winner, score margin, criteria wins, breakdown) and input flexibility. It does not mention error handling or tie-breaking behavior, but for a pure computation tool, the disclosure is solid and non-misleading.

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 two sentences, front-loaded with the primary purpose, and every clause adds useful information (outputs, input forms). No filler or redundant details.

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 tool has 6 parameters, nested objects, and multiple input formats, and no output schema. The description covers the essential usage (how to pass options, what is returned) and the schema documents criteria/scores. It is complete enough for an agent to invoke correctly, though it omits guidance on method selection or behavior for invalid input, which the schema partially addresses via defaults and enums.

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 50%, with criteria and options already well-documented. The description adds value by explaining the two ways to pass options (option_a/option_b vs 2-element options array), which is not obvious from the schema alone. However, it does little to elaborate on scores or criteria structure beyond what the schema provides, so it only partially compensates for coverage gaps.

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 opens with 'Head-to-head comparison of exactly two options', which is a specific verb ('comparison') and resource ('two options'), and details the return values (winner, score margin, criteria wins, per-criterion breakdown). This clearly distinguishes it from sibling tools like score_options or sensitivity_analysis.

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 phrase 'exactly two options' sets a clear constraint on usage, and the description clarifies the two acceptable input formats (option_a/option_b or 2-element options array). However, it does not explicitly mention when to use alternative tools like score_options for more than two alternatives, so it stops short of full exclusion guidance.

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