analyze_html

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

With no annotations, the description carries the full burden. It clearly states the tool parses and checks for specific items (render-blocking, meta tags, etc.), indicating a read-only analysis. However, it omits potential details like whether it fetches the page itself, or any rate limits or dependencies.

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 a single, front-loaded sentence that efficiently communicates the tool's core function and specific areas of analysis. Every phrase adds value with no redundancy.

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 simplicity (1 parameter, no nested objects) and no output schema, the description covers the what and checks well. It lacks details about the return format or output structure, which could help an agent understand what to expect. Still, it is largely adequate.

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?

There is only one parameter 'url', which is fully described in the schema (type, format, description). The tool description does not add extra semantics for this parameter beyond what the schema provides, so a baseline score 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 specifies a clear verb ('Parse') and resource ('HTML of a page'), and lists actionable checks (render-blocking resources, meta tags, script strategy, head optimizations). This distinguishes it from sibling tools like analyze_css or analyze_javascript.

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 for HTML-level performance and optimization checks, but does not explicitly state when to use this tool over siblings such as analyze_css or run_lighthouse. No 'when not to use' or alternative suggestions are provided.

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