Diff two Rego policies

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the tool is safe. The description adds that evaluations run in parallel and details the return format ('equal: true/false', raw results, 'changedPaths'). This goes well beyond the annotations, providing full behavioral context.

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 three sentences, front-loading the core purpose and then detailing behavior and parameters. Every sentence adds value with no redundancy or filler.

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?

With 8 parameters, 1 required, and no output schema, the description covers return values, parameter relationships, and key behavioral traits. It lacks error conditions or edge cases but is sufficient for a diff tool.

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 description coverage is 100%, so baseline is 3. The description adds meaning by explaining mutual exclusivity between source/path pairs and that the same input and query are used for both evaluations. This enriches understanding beyond the schema alone.

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 evaluates the same query against two policies and compares results. It specifies the verb ('Evaluate' and 'compare'), the resources ('two policies or two versions'), and distinguishes from siblings by focusing on diffing rather than single evaluation.

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 provides explicit use cases ('verifying that a refactor preserves behavior' and 'understanding exactly where two policies diverge') and explains parameter relationships (mutual exclusivity of sourceA/pathA). However, it does not explicitly state when not to use this tool or list alternatives among siblings.

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