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

Annotations already provide readOnlyHint and openWorldHint. The description adds significant behavioral context: pricing model (subscription or per-call) and the detailed output structure (recommendations, implementation guide, competitive analysis, score improvement). This goes beyond annotations to help the agent understand the tool's cost and output richness. However, it doesn't mention rate limits or authentication beyond the payment link.

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 concise with a clear opening statement, followed by pricing and a bullet list of included features. Every sentence adds value, though the pricing details could be seen as secondary. The structure is front-loaded and easy to parse.

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 the tool's complexity (premium audit with multiple deliverables) and the lack of an output schema, the description adequately lists what the tool returns (recommendations, guide, competitive analysis, score estimates). It does not specify the return format (e.g., JSON or text), but for a complex tool the level of detail is sufficient.

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 does not add any information about parameters, their formats, or relationships. It focuses on the tool's purpose and outputs rather than parameter usage. No extra value 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?

The description clearly identifies it as a 'Premium AEO audit' and indicates it includes everything from the sibling tool 'audit_domain' plus additional features. The purpose is clear, though it could be more explicit about the action (e.g., 'Perform a premium audit'). It effectively distinguishes itself from siblings by specifying the premium nature.

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 by comparing to 'audit_domain' (basic vs premium), but does not explicitly state when to use this tool versus alternatives like 'quick_check' or 'suggest_queries'. No clear when-not or alternative guidance beyond the cost hint. Context is present but not fully explicit.

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