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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly states that the html field replaces the entire page (full replacement, not patch) and that assets, if provided, replace ALL existing assets. It also discloses the authentication requirement via edit_key or api_key, which is critical context for a mutation operation.

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 concise and front-loaded with the main purpose, but it contains a slight redundancy: the authentication requirement is stated twice ('Requires authentication...' and 'IMPORTANT: You must provide either edit_key or api_key...'). This extra sentence adds little value and could be trimmed, preventing a perfect score.

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?

For a tool with 6 parameters, a nested assets object, and no output schema, the description provides solid context: when to use, what the html replacement entails, asset behavior, and authentication. It does not describe the response format or error cases, but these are not essential for selecting and invoking the tool given the rich schema.

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%, so the baseline is 3. The description adds value beyond the schema by emphasizing that edit_key or api_key must be provided for authentication, even though they are not marked as required in the schema. It also reiterates the full-replacement semantics for html and the replace-all behavior for assets, reinforcing critical parameter implications.

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 updates an existing published website with new HTML content, using a specific verb ('Update') and resource ('existing published website'). It distinguishes from siblings by focusing on modifying a previously published site, as opposed to creating (publish_website), deleting (delete_website), or checking status (get_website_status).

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 explicitly says 'Use this when a user asks you to modify, edit, or change a site you previously published,' providing clear context for when to use the tool. It does not explicitly name alternatives or when-not-to-use scenarios, but the context implies it is for existing sites, which differentiates it from publish_website.

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