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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is known. The description adds meaningful behavioral context: the default model is free, Anthropic calls require a BYO key with direct cost to the user, and the response structure includes per-model score, confidence, signals, and raw_response. This complements the annotations without contradiction.

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 front-loaded with the core purpose and result, then details the default model and optional Anthropic integration, and ends with use cases. It is efficient and avoids fluff, though it could be slightly tighter. Each sentence earns its place, so it merits a 4.

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 read-only, idempotent tool with no output schema, the description adequately explains the return format (per-model structure plus combined view) and covers all parameters via the schema. It also provides usage context. No critical information is missing for an agent to call it correctly, though error handling and rate limits are not addressed.

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 all four parameters are already documented in the input schema. The description adds marginal value by reiterating the default model and the _apiKey's purpose, but it does not introduce new parameter semantics beyond what the schema provides. Baseline 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 states a specific verb ('Probe') and resource (LLMs), and clearly defines the outcome: scoring visibility from 0-100 per model. It goes beyond the title by specifying the default model and the option to probe Anthropic, and lists concrete use cases, making the purpose unmistakable even among many sibling tools.

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 contexts for use ('AI-marketing audits, pre-launch brand checks, competitive monitoring'), which implicitly tells when to invoke it. However, it does not explicitly name alternatives or state when not to use it, so it falls short of the highest level of guidance.

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