create_inbox

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

With no annotations, the description carries full burden. It explains the auto-assignment of domain if domain_id omitted, optional parameters, and webhook endpoint behavior. It does not disclose rate limits or auth needs, but the creation behavior is well described.

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 well-structured with a summary paragraph and Args list. It is clear and informative, though slightly verbose for the display_name explanation; still efficient.

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?

Given 5 parameters (1 required) and an output schema (not shown), the description covers all parameters and provides context. It does not describe return values, but output schema likely handles that. Minor gap: no mention of default values beyond domain auto-assignment.

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 has 0% description coverage, but the description thoroughly explains each parameter: local_part (part before @), domain_id (optional, auto-resolved), name (agent name, display_name fallback), display_name (with example), and webhook_endpoint (notification URL). This fully compensates for missing schema descriptions.

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 clearly states 'Create a new inbox for receiving emails' and explains the email address format. It distinguishes from sibling tools like delete_inbox, list_inboxes, etc., by focusing on creation.

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 implies use when an inbox needs to be created for email receiving, but does not explicitly state when not to use or mention alternatives among siblings (e.g., send_email for sending, not receiving).

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