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

With no annotations, the description carries the behavioral burden and handles it well by disclosing that 'domains replaces the whole list' and that at least one domain is required. It also notes the optional rename behavior. It does not cover permission requirements or the effect on an existing key, but the core destructive-replacement semantics are clear.

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 two sentences with no filler. The main action is front-loaded, and the critical caveat about replacement semantics is placed immediately afterward.

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 low-complexity update operation with three parameters and no output schema, the description is nearly complete: it covers required inputs, replacement behavior, and the optional rename. Minor gaps are the lack of return-value expectations and behavior for an invalid site_id.

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 description coverage is 0%, and the description compensates well for the two most nuanced parameters: domains are explained as a whole-list replacement requiring at least one item, and name is described as an optional rename. site_id is not explicitly defined but is inferable from the tool name and the integer parameter name.

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 action: replacing the list of domains valid on an Agent Detection integration's publishable key, with an optional rename. This distinguishes it from sibling tools like agent_detection_create_site and agent_detection_list_sites.

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 when to use the tool via the example 'to add a staging or www host', but it does not explicitly mention when not to use it or present alternatives such as creating a new site. Usage context is present, but routing guidance is left to inference.

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