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

The description adds no behavioral context beyond the destructiveHint already present in annotations. It doesn't mention irreversibility, downstream effects, or any side effects. With destructiveHint=true, the destructive nature is already declared, but the description contributes nothing additional.

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 a single concise sentence with no filler. It front-loads the action and resource, and every word earns its place.

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 one-parameter destructive action, the description, destructiveHint, and schema fully cover what an agent needs to call it correctly. The schema documents where the ID comes from, and the output schema exists, so no return-value explanation is needed.

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%, and the domain_id parameter is already described as the ID to remove. The description's 'by its ID' only restates what the schema already says, so it adds no meaningful parameter semantics beyond the baseline.

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 uses a specific verb and resource: 'Remove a custom domain by its ID.' It clearly distinguishes this from the sibling remove_email_domain by naming 'custom domain,' and the action is unambiguous.

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 makes the use case clear: use this when a custom domain should be removed by ID. It does not explicitly mention alternatives or exclusions, but the resource label 'custom domain' is enough to route an agent correctly against related siblings like add_domain and remove_email_domain.

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