list_inboxes

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

No annotations are provided, so the description must carry the burden of behavioral disclosure. It reveals the list operation and the email address format, but lacks transparency on potential issues like pagination, ordering, or whether the results are sorted. As a read operation, destructive hints are not needed, but additional behavioral details would be helpful.

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 very concise: three short paragraphs that front-load the purpose, then clarify scope, and finally provide a useful detail about email addresses. Every sentence adds value, and the 'Args' line is acceptable even though it partially echoes the schema.

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 the tool's simplicity (1 optional parameter, output schema exists), the description is largely complete. It covers the core functionality, filtering, and a key output detail. However, it lacks any mention of pagination or result ordering, which might be assumed for a list operation.

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?

With 0% schema description coverage, the description compensates well by explaining the domain_id parameter: 'Filter by domain (optional, lists all if omitted)', and adds context about the email address structure. It adds meaning beyond the schema, though it could cross-reference domain_id with list_domains.

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 'List inboxes' and explains the scope: without domain_id lists all, with domain_id filters. The verb 'list' and resource 'inboxes' are specific. However, it does not explicitly differentiate from sibling tools like 'list_domains' or 'list_threads', but the function is distinct enough.

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 when to use the domain_id filter versus not, but provides no guidance on when to use this tool over others or when not to use it. There are no explicit alternatives mentioned, though the purpose is straightforward.

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