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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context: each item indicates whether the 24-hour window is open and how much time remains, which is beyond the schema. However, it does not disclose pagination, ordering, or whether the search parameter filters by contact name or message content.

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 and front-loaded with the core concept ('The inbox'), then explains the window indicator and the two key filters. Every sentence earns its place, though the parameter explanations could be slightly more 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 read-only list tool with no output schema, the description covers the main purpose and the two most important filters. However, with 7 parameters and no output schema, an agent would benefit from knowing what fields each conversation item contains, how pagination works, and what the search parameter matches. The description is adequate but not complete.

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 description coverage is only 14%, so the description must compensate. It explains the meaning of 'state' and 'kind' enums, which is helpful, but the other five parameters (limit, search, unread, accountId, workspaceId) are left undocumented in both the schema and description. The workspaceId parameter has a schema description, but the rest rely on naming conventions.

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 lists inbox conversations across Instagram DMs, Facebook DMs, and Threads mentions, and distinguishes it from the sibling list_mentions by covering both DM and mention kinds. The verb 'list' plus the resource 'inbox conversations' is specific and unambiguous.

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 default state ('open') and the kind filter ('dm or mention'), giving an agent enough context to know when to use this tool. It does not explicitly name alternatives or exclusions, but the sibling list_mentions is implicitly differentiated by the mention coverage. No explicit when-not-to-use guidance is provided.

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