Repost a Threads post

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

The description discloses that this creates a NEW post, which is a side effect not captured by annotations (destructiveHint=false might mislead, but the description clarifies it does create new content). It also transparently reveals that no un-repost endpoint exists, suggests a possible undo via delete_thread with the returned media id, but warns that Meta does not document it and advises verification. This goes beyond annotations and fully covers behavioral nuances.

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 dense but every sentence provides necessary information: purpose, usage context, side effects, undo limitations, and prerequisites. There is no redundancy; it front-loads the core intent and then covers operational details efficiently. It earns its length.

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 tool that creates a new post, it covers the action, the input source, the confirmation step, the lack of documented undo, the cost, and the connectivity requirement. It even mentions the returned media id, which helps in chaining with delete_thread. Given there is no output schema, this description provides sufficient context for an agent to call it 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?

The only parameter, postId, is fully described in the schema ('the Threads post id to repost'). The description adds value by explaining that it accepts any Threads post id and listing the tools that return such ids, enriching the schema's minimal definition. This justifies a score above the baseline of 3 for full schema coverage.

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 action (repost), the resource (existing Threads post), and the target (brand’s own profile). It distinguishes itself from creating new posts by comparing to a retweet and explicitly noting it does not copy text. The mention of 'no way to do it previously' adds context that helps the agent differentiate it from other posting tools.

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?

Provides explicit guidance on when to use: it works on any Threads post id and names the sibling tools that return such ids (list_threads_posts, list_threads_mentions, search_threads_keyword). It instructs the agent to get user confirmation before executing, which is a clear behavioral directive. It also states the prerequisite (Threads connected) and the cost (0 credits).

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