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

The readOnlyHint annotation already establishes safety, so the description adds value by disclosing that each item reports whether the 24-hour window is open and how much time remains. This is useful behavioral/return information beyond what annotations or schema provide.

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?

Three short sentences with no filler; the opening 'The inbox' orients the agent immediately, and the filter hints and item-level behavior are stated efficiently. Every sentence contributes.

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?

With no output schema and 7 parameters, the description covers the core concept and one important return detail but omits guidance on filtering via search/unread, pagination via limit, and account selection. It is minimally sufficient but leaves meaningful gaps for a 7-parameter 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?

Schema description coverage is only 14%, so the description must compensate for undocumented parameters. It does clarify state's default ('open') and maps kind to the conversation types mentioned earlier, but limit, search, unread, accountId, and workspaceId receive no explanatory value beyond the schema.

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?

States a specific verb ('list') and resource ('inbox conversations'), and clearly defines the scope: DMs on Instagram/Facebook plus mention threads on Threads. This distinguishes it from sibling tools like read_conversation or list_mentions, which focus on individual messages or mentions only.

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 usage as an inbox overview and mentions state/kind filters, which gives some context on how to use it. However, it does not explicitly say when to prefer this tool over alternatives like list_mentions or read_conversation, nor does it state exclusions.

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