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

With no annotations, the description carries the full burden. It discloses the signature-based detection method, output format (JSON), pricing ($0.02 USDC per call), and specific info returned (server headers, security posture). It does not mention permissions or rate limits, but overall provides good transparency for a read-only tool.

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 relatively long but every sentence adds value, listing categories and examples. It front-loads the main purpose and is well-structured for quick comprehension.

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 complexity of detecting multiple technologies, the description covers what the tool does, what it returns (JSON with server headers, etc.), and even includes pricing context. Without an output schema, it adequately informs the agent of the expected response.

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 coverage is 100% with one parameter 'url' described as 'URL or domain to fingerprint'. The description adds value by clarifying that both 'url=' and 'domain=' forms are acceptable, improving usability beyond the schema's terse description.

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 explicitly lists what the tool detects (CMS, JS framework, analytics, etc.) and clearly distinguishes it from sibling tools like 'domain-check' or 'brand-visibility' by focusing on technology fingerprinting from a live homepage.

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 explains how to use the tool ('Pass url= or domain=') but does not provide explicit guidance on when to choose this tool over alternatives or when not to use it. Usage context is implied by the tool's purpose.

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