zen_html

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

No annotations are provided, so the description must carry the full burden. It mentions a size limit ('Cap 100KB'), which is a useful behavioral trait. However, it fails to disclose other important behaviors, such as the outcome if the element is not found, whether the operation is read-only, or any authentication requirements.

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 extremely concise at two sentences. The first sentence states the core purpose, and the second adds a critical constraint. Every sentence earns its place; there is no redundant information.

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 has two parameters, no output schema, and no annotations, the description is incomplete. It does not explain how to use the parameters, what the return value looks like, or edge cases (e.g., element not found). The only extra context is the 100KB cap, leaving significant gaps for an agent to safely invoke 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?

The input schema has two parameters (selector and tab_id) with zero schema description coverage. The description does not explain what these parameters mean, how they affect the output, or any constraints (e.g., selector format, default tab behavior). The agent gains no additional semantic insight beyond the parameter names.

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 action ('Return') and the resource ('outerHTML of a specific element'). It also adds a size constraint ('Cap 100KB'), which further clarifies the tool's scope. Among siblings, 'zen_html' is distinct from tools like 'zen_dom' or 'zen_markdown', as it specifically returns raw HTML.

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 obtaining HTML content of an element but provides no explicit guidance on when to use this tool versus alternatives like 'zen_dom' or 'zen_markdown'. It does not mention when not to use it or any prerequisites, leaving the decision to the agent's inference.

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