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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description goes beyond these by disclosing that the tool probes each entity with ai_visibility_check, ranks by score, and returns a structured result with score, confidence, and signal density. This adds useful 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 only two sentences. The first sentence states the action and method, the second provides a use case and output format. Every sentence earns its place with no redundancy or fluff.

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?

The description covers purpose, method (probes ai_visibility_check), output format (ranked list with score/confidence/signal density), and a concrete use case. Although there is no output schema, the description supplies return details. Given the moderate complexity and well-documented parameters, it is nearly complete.

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?

The schema provides 100% coverage for all four parameters with descriptive text. The description does not add meaningful parameter semantics beyond what is already in the schema, so the baseline score of 3 is appropriate.

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 opens with 'Compare AI visibility across multiple entities side-by-side', a specific verb+resource that clearly states the tool's function. It distinguishes itself from sibling ai_visibility_check by explicitly mentioning multi-entity comparison and ranking, making the purpose unambiguous.

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 clear context with 'Useful for competitive AI-marketing audits' and an illustrative query. It implies this tool is for multi-entity comparison vs. single-entity checks, but does not explicitly name alternatives or list exclusions, so it stops short of a 5.

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