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

Beyond the readOnlyHint/openWorldHint annotations, the description discloses internals an agent could not otherwise know: the comparison is run twice with order swapped and averaged, this exists to counter a second-option bias, and disagreement resolves to a tie. That materially changes how results should be interpreted and reported.

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, front-loaded with the core purpose and then the tie-breaking behavior; no filler. The first sentence is a subject-less fragment, which slightly blunts immediate readability.

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 read-only judging tool with no output schema, the description covers the most important unknown: that the outcome may be a tie. It does not describe the response shape or how the averaged verdict is represented, though it does confirm the ordering behavior an agent must account for.

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 coverage is only 50% (context and question are described in the schema; version_a and version_b are not), and the description does not compensate for the gap, referring only obliquely to "a stated purpose." Parameter names are largely self-explanatory, which keeps this from being a 1, but the description adds essentially no parameter meaning.

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 opening sentence states a specific comparison task ("Which of two versions is stronger for a stated purpose") with a clear input pair and evaluation dimension, so an agent can tell it apart from pass/fail tools like judge_yes_no. It does not, however, contrast itself with the closest sibling, judge_choice, which may also be a pairwise comparison, leaving some ambiguity.

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?

Usage is implied by "for a stated purpose" and the two-version input shape, but there is no explicit statement of when to pick this over judge_choice or grade_with_rubric. No exclusions or prerequisites are given.

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