Repost a Thread

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

Annotations already signal the operation is not read-only and not destructive. The description adds little beyond restating the action and the target profile. It does not disclose permissions needed, whether the repost is publicly visible, reversibility, rate limits, or any other side effects beyond what is obvious from the verb.

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 one direct sentence followed by a compact argument list. It front-loads the core action and resource, contains no filler, and every sentence earns its place.

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 with two required parameters and no output schema, the description is minimally sufficient to identify the action and arguments. However, it lacks return-value expectations, auth or permission context, and any guidance on when to use this versus sibling publishing tools, so it is not fully complete for confident autonomous invocation.

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 schema leaves threads_user_id undocumented, and the description compensates by labeling it 'Your Threads user ID'. media_id is given a 'Thread media ID' qualifier that clarifies the parameter, and response_format already has a full schema description. Combined, all three parameters are effectively documented.

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 uses a specific verb 'Reposts (shares)' with a clear resource 'existing thread' and target 'your profile'. It is immediately distinguishable from the many publish/create siblings in the tool list, which involve new content rather than sharing an existing thread.

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 the use case—sharing an existing thread—but provides no explicit guidance on when to choose this tool over alternatives like threads_publish_text or threads_publish_image. There are no exclusions, prerequisites, or conditions stated, so the agent must infer selection from the tool name alone.

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