Look up a website's technology stack

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

With no annotations provided, the description fully carries the behavioral burden and excels: it discloses the detection method (HTML and server headers), explains the client-side JavaScript limitation, and interprets sparse results as 'little detectable, not that the site runs nothing.' It even notes plan quota impact. This is exemplary behavioral disclosure.

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 dense and front-loaded with the core purpose, followed by targeted use cases and critical caveats. Every sentence contributes: the category list specifies scope, the usage sentence gives context, the JavaScript limitation is vital, and the quota note is actionable. No wasted words.

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?

Despite having no output schema, the description fully prepares an agent to use the tool correctly: what it detects, how detection works, its limitations, how to interpret results, and a billing/quota consequence. Nothing essential for invoking this single-parameter tool is missing.

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 already documents the url parameter at 100% coverage, including the bare-domain note, so the description adds little parameter-specific meaning. Baseline 3 is appropriate because the schema does the heavy lifting and the description complements it without needing to repeat details.

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 a specific verb and resource ('Detect the technologies a website runs') and enumerates the technology categories covered, which is unambiguous. However, it does not explicitly differentiate itself from the sibling tools batch_lookup and compare_stacks, so it falls short of a 5.

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 use-case context: 'research a competitor, qualify a sales prospect, or check what a site is built with.' It does not, however, mention when to prefer this tool over the sibling tools or when to avoid it, so it lacks explicit exclusions or alternative routing.

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