Diff two versions of an OpenAPI spec for breaking changes

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

No annotations are provided, so the description must carry the behavioral disclosure. It does so by stating what it reports and by explicitly guaranteeing no side effects on the currently loaded spec ('Does not affect the spec currently loaded for the other tools'). It does not mention network/error behavior, but the core behavior and safety profile are clear.

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, no filler. The first sentence packs the core action, input types, example, and output classification; the second sentence adds the crucial side-effect guarantee. All content earns its place.

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?

Despite no output schema, the description tells the agent what the tool returns conceptually: added/removed endpoints, request/response schema changes, and a distinction between breaking and safe changes. Combined with the input format and side-effect note, an agent can decide when and how to invoke it.

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?

Both parameters have schema descriptions ('The before spec', 'The after spec'), so schema coverage is 100%. The description adds the valid input type (URL or local file path) and illustrates intended usage with the old tag vs current main example, which is meaningful beyond the schema.

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 action ('Compare two OpenAPI/Swagger specs'), a clear subject (the two specs), and the concrete output (added/removed endpoints, schema changes, breaking vs. safe). This differentiates it from siblings that load, list, call, or validate against a single spec.

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?

Provides clear context: use this when you need to compare an old version (e.g., old tag) against the current main to identify breaking changes. It notes that it does not affect the spec used by other tools, implying it is a safe analysis tool, but it does not explicitly name alternative tools or exclusion conditions.

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