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

With no annotations, the description carries the burden of disclosing behavior. It states the input (2-5 addresses) and output (winner + rationale), which is useful. However, it does not disclose tie-breaking logic, how trust is computed, error handling, or whether the operation is read-only. Given the absence of annotations, this is a moderate gap, so a score of 3 is appropriate.

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 a single, front-loaded sentence that states the core function and expected output. Every phrase adds value—'head-to-head', '2-5', 'winner address', and 'one-sentence rationale' are all informative. There is no superfluous content, making it highly concise.

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 a simple tool with one parameter and no output schema, the description provides enough context for an agent to invoke it correctly: what to pass (addresses), the count constraints, and what to expect back (winner + rationale). It leaves out minor edge-case behaviors (ties, invalid addresses), but these are not critical for basic usage given the tool's simplicity. The sibling context also helps set expectations.

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?

The input schema covers 100% of the parameter ('addresses' with min/max items and description). The tool description adds no new information about the parameter beyond what the schema already provides. With high schema coverage, the baseline is 3, and no additional meaning is provided, so it stays at 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's function: 'Head-to-head trust comparison of 2-5 merchant addresses.' It includes a specific verb ('comparison'), resource ('merchant addresses'), and scope ('2-5'), differentiating it from siblings like check_trust (single check) and leaderboard (ranking). It also mentions the output ('winner address and a one-sentence rationale'), making the purpose unambiguous.

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 implies when to use this tool: when you need a side-by-side trust comparison of 2-5 addresses and a winner. It does not explicitly reference alternatives or exclusions, but the '2-5' constraint and 'head-to-head' context clearly distinguish it from check_trust (single) and leaderboard (broad ranking). No misleading guidance is present.

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