Fit Check

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

Annotations include readOnlyHint=true, so the read-only nature is covered. The description adds valuable context beyond annotations by disclosing the output schema (complete list of fields) and the probabilistic model (normal, half-band = 3-sigma). No contradictory information; the description enriches the behavioral profile without restating the annotation.

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 compact, two sentences, with the purpose front-loaded. It packs input format and output details efficiently without verbosity or repetition. Every word adds value.

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 there is no output schema, the description fully specifies the return values and their types, and it explains the input format. It does not mention error handling or interpretation of clearances, but the core information needed to call the tool correctly is present. It is adequate for an agent to use without additional docs.

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 0% (parameters are empty objects), so the description carries the full burden. It specifies the structure of 'hole' and 'shaft' as {nominal, plus, minus} or {nominal, tol}, which is essential for correct invocation. This goes beyond the schema, though it omits units or precision, so it is not perfect but highly compensating.

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 uses a specific verb ('Classify') and resource ('a hole/shaft pair'), and clearly states the output structure. It distinguishes itself from related siblings like tolerance_stackup or fit_class by being explicit about the classification logic and return fields.

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 usage (classify a hole/shaft pair) but does not explicitly contrast with alternatives such as the 'fit_class' sibling or mention when not to use it. There is no guidance on selecting this over related tools like tolerance_stackup, so an agent may not know when this is the preferred tool.

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