configure_inbound_domain

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

Annotations already mark the tool as idempotent and non-destructive, and the description usefully adds that it returns the MX record to publish. It does not contradict annotations and adds a key behavioral detail beyond the schema.

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, front-loaded sentence that states the action, purpose, and return value without wasted words. It is concise and well structured.

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 configuration tool with three parameters, no output schema, and idempotent/non-destructive annotations, the description covers the core purpose and return value. It could mention prerequisites like domain verification, but the schema and annotations already provide sufficient operational context.

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 provides 100% coverage with examples for domain and subdomain, and a clear description for the optional webhook_url. The tool description adds no extra 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 uses a specific verb ('Configure') and names the exact resource ('inbound email routing for a subdomain'), with the clear outcome that replies land in the MisarMail unified inbox. This distinguishes it from sibling domain tools like add_domain or verify_domain.

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 provides clear context by stating the purpose: configuring routing for replies to land in the unified inbox. It does not explicitly name alternatives or exclusions, but the intent is unambiguous enough for an agent to know when to use it.

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