list_inboxes

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

There are no annotations, so the description carries the full burden of behavioral explanation. The verb 'list' reasonably implies a read-only operation with no side effects, and the API key scoping adds a useful constraint. It does not disclose return format, pagination, or whether deleted/inaccessible inboxes are filtered out, but this is acceptable for a basic listing 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?

The description is a single, efficient sentence that immediately states the action and the scope, without any redundant words. It is appropriately minimal and well-structured for the tool's simplicity.

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 parameterless list tool, the description is nearly complete: the agent knows what to invoke and what result to expect conceptually—a list of inboxes. The lack of an output schema means the exact response shape is not specified, but the description communicates enough for straightforward usage.

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 tool has zero parameters, so the schema already fully defines the input. The description adds meaningful scope context by stating that the result is limited to inboxes available to the API key, which helps the agent understand why no parameters are needed.

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 specific verb ('List') and resource ('all inboxes') scoped by the API key. It is easily distinguishable from sibling tools like create_inbox or read_messages that target other operations.

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 conveys that this is the tool to use when the agent needs to list or enumerate available inboxes, since no sibling has a listing action. However, it does not explicitly mention when to prefer alternatives like read_messages or create_inbox, leaving some inference to the agent.

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