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

Annotations already establish read-only, idempotent, non-destructive behavior. The description adds that the checks run in parallel and produce an overall score and verdict, providing useful functional context beyond the annotations. No contradiction found.

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 two sentences: the first front-loads the core purpose and behavior, the second provides usage guidance. Every sentence earns its place with no redundancy or unnecessary detail.

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 one parameter, full schema coverage, and strong annotations, the description adequately explains the tool's function, its parallel execution, and the output of an overall score and verdict. While it doesn't detail the exact response format, that's not required given the simplicity of the 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 already covers the URL parameter and mentions 'combined security posture check (headers, reputation, and related signals)'. The tool description adds minimal extra detail beyond what the schema already provides, so it meets the baseline for 100% coverage without significantly enriching parameter meaning.

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 performs a combined website check covering security headers, URL reputation, and passive subdomain discovery, with an overall score and verdict. It explicitly differentiates from siblings by directing use of individual tools for single signals, so an agent can easily distinguish it.

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 gives explicit usage guidance: use this combined tool for an overall security posture check, and use individual tools when only a single signal is needed. This directly tells the agent when to choose this tool versus the alternatives.

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