Threads mentions of the brand

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds important scope context: 'anywhere, not just under your own posts', which clarifies the tool's behavior beyond what annotations provide. It also frames the output as useful for ad copy and mine_angles, though that's purpose rather than behavior. No contradiction with annotations.

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 two sentences with zero waste. The first sentence states the core function and scope; the second provides value context and a clear alternative. It is front-loaded and precise.

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 tool with one parameter and no output schema, the description provides enough context: it clearly states what is returned (posts with mentions) and how to use it. It lacks details on ordering or pagination, but these are minor for a read-only list tool. It is complete enough for an agent to call correctly.

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 100% and the single parameter 'limit' is already fully documented in the schema. The description does not add any additional parameter semantics, so the baseline of 3 is appropriate.

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 states a specific verb (list), resource (mentions of the brand on Threads), and scope (anywhere, not just under own posts). It also explicitly names the sibling tool list_threads_replies and differentiates from it, making the purpose 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 explicitly says when to use this tool: for brand listening, gathering objections, questions, and exact customer language. It also directs to use list_threads_replies instead when the user wants conversation under a specific post. This is clear when/when-not guidance with a named alternative.

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