list_inboxes

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

No annotations are provided, so the description is the sole source of behavioral context. It discloses the scope behavior (all domains vs. specific domain) and the local_part relationship, but does not explicitly state read-only status, side effects, or authorization requirements.

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 compact, starting with a clear action and then elaborating on the optional parameter and the email address format. It is well-structured and avoids unnecessary verbosity.

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 simple list operation with one optional filter and an output schema, the description covers the core behavior and parameter meaning. It could optionally mention pagination or ordering, but these are likely captured in the output schema or are not critical for this tool.

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 schema only defines domain_id as an optional string. The description adds that it filters by domain and that omitting it lists all inboxes, providing necessary semantic meaning that the schema lacks.

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 the tool's function with a specific verb ('List') and resource ('inboxes'). It then explains the two modes (all domains vs. specific domain) and provides useful context about email address composition, making its purpose unambiguous and distinct from sibling tools.

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 explains the behavioral difference when domain_id is present or omitted, which serves as clear usage guidance. It does not explicitly name alternative tools, but the context makes it obvious when to use this tool versus others like create_inbox or delete_inbox.

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