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

With no annotations, the description carries the full burden, and it does add one real behavioral trait: the Pro plan requirement. However, for a mutation tool it omits reversibility (how to unlock, whether null origins clears the restriction), whether omitted fields are left untouched or reset, and what permissions/ownership are needed beyond what the schema says.

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?

Two short sentences, front-loaded with the effect and followed by the plan constraint. Nothing is wasted and nothing important is buried.

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 4-parameter mutation with no annotations and no output schema, the description is thin: it doesn't state what the tool returns, whether the change is idempotent, or how omitted parameters are treated. The core effect and plan gate are present, so it is adequate but with clear gaps.

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 75%, with slug, origins, and ownerToken already documented in the schema. The description only loosely maps "lock with a token (private)" to the private/ownerToken pair and says nothing about the semantics of the undocumented `private` boolean or partial-update behavior.

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?

Names a specific verb (lock/restrict) and resource (mock) plus the two things being set: private token access and allowed browser origins. This distinguishes it reasonably from siblings like set_domain, set_behavior, and set_response, though it never names those siblings explicitly.

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 "Pro plan" note is a useful prerequisite, but there is no explicit statement of when to use this versus set_domain or set_behavior, and no indication of when-not to use it (e.g. downgraded accounts, already-locked mocks). Usage is only implied by the described effect.

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