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

Adds real behavioral context beyond the annotations: the domain 'stops serving on the next request' (timing/eventual effect) and 'its certificate stops renewing', plus a clear statement that the share URL is unaffected. It does not contradict destructiveHint=true or idempotentHint=false, and it usefully narrows the blast radius of a destructive 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?

Two tight sentences with zero waste; the core action is front-loaded and the effect/non-effect clauses are packed into the second sentence.

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 an output schema present, the description needn't document return values, and it covers the salient side effects of a destructive operation. Minor omissions (whether the domain can be re-attached, any preconditions) keep it from a 5.

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 100% with only two top-level parameters, so the schema already documents both fields fully. The description adds nothing about parameter format or constraints, which is the expected baseline here (though the schema's own 'hostname to attach' wording is a mild wart it does not correct).

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?

States a specific verb (detach) and resource (custom domain) scoped to 'a spawnpoint project', so the operation is unambiguous. It does not explicitly name the sibling it inverts (add_custom_domain) or distinguish itself from verify_custom_domain, so it falls short of full sibling differentiation.

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?

Usage is implied by the verb rather than stated: there is no when-to-use, no prerequisites (e.g., must the domain be verified first?), and no note about re-adding via add_custom_domain. Adequate for a straightforward detach operation but no explicit routing guidance.

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