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

The readOnlyHint=true annotation already signals this is a safe, non-mutating evaluation, and the description is consistent with that. The description adds useful trigger context (single-caller branches, exposed internal representation) but doesn't disclose output shape or how the evaluation is reported. With annotations covering the safety profile, a 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?

Three tight sentences: purpose first, then positive triggers, then negative triggers with named alternatives. No filler, and the exclusions are front-loaded in the same breath as the positive cases.

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 zero-parameter, read-only evaluator with no output schema, the description provides the essential routing information an agent needs to pick this tool over 16 siblings. It is nearly complete; the only minor gap is that it doesn't indicate what the evaluation returns, though no output schema exists to relieve it of that.

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?

Zero parameters, so per the rubric the baseline is 4. The schema has no properties for any parameter to describe, and the description doesn't need to compensate for anything.

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?

States a specific evaluation task ('Evaluates whether interfaces are appropriately general-purpose') with a clear resource (interfaces). The sibling set is large and purpose-adjacent (abstraction-quality, deep-modules, information-hiding), and while the description names two siblings it excludes, it doesn't sharply differentiate from the unnamed ones, so it lands at 4 rather than 5.

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?

Explicitly covers when to use ('when checking interface generality, when if-branches or parameters serve only one caller') and when not to ('Not for information leakage ... use information-hiding', 'or auditing configuration parameters (use pull-complexity-down)'). Names both alternatives and the conditions that route to them, leaving little to inference.

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