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

Annotations already communicate idempotency, non-read-only, and non-destructive behavior. The description adds meaningful context beyond that: a Valet-account prerequisite, the clarification that the password is a shared visitor credential rather than a Valet credential, and the 72-byte limit. This does not contradict any annotation.

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 front-loaded with the core purpose and mode definitions, and the password clarification is compact. It is slightly redundant with the already-detailed schema descriptions, but it contains no fluff and reads clearly.

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?

With full schema coverage, useful annotations, and no output schema, the description plus schema gives the agent everything needed to invoke the tool correctly: prerequisite, mode effects, password constraint, and required/optional fields. There is no critical gap for calling this 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 100% parameter coverage and already explains mode semantics and password constraints. The description largely restates the schema's mode and password content rather than adding new parameter-level meaning, so the baseline 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 opens with a specific verb and resource ('Set who can reach a website') and clearly enumerates the three access modes with their effects. It unambiguously states what the tool does, but it does not explicitly distinguish itself from sibling tools such as share_site or publish_site, which prevents 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?

It provides a concrete prerequisite ('Requires connecting a Valet account') and explains the scenarios for each mode, so the agent knows when the tool is applicable. However, it does not say when to prefer this tool over alternatives like share_site or publis_site, leaving some routing to inference.

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