post_reel

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions that the video URL must be public, which is an important prerequisite. However, it does not describe potential side effects (e.g., the post appears publicly), required permissions, or error scenarios, leaving some transparency gaps.

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 extremely concise, fitting into a single sentence. It front-loads the primary action and then provides the essential video requirements. Every part is informative, with no filler or redundancy.

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?

Given that there are no annotations and no output schema, the description should provide more context to fully understand the tool's behavior. It does not mention what the tool returns, any authentication needs, or potential failure modes. For a posting tool with 4 parameters, the description is minimal and leaves several important aspects unexplained.

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 description coverage is 50% (2 of 4 parameters have descriptions). The tool description adds no parameter-specific details beyond what is in the schema. For example, it does not clarify the expected format of video_url or caption, which are not described in the schema. Thus, the description does not compensate for the missing parameter documentation.

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's purpose: 'Dang Reel (video) len Instagram tu URL video cong khai' translates to 'Post Reel (video) to Instagram from public video URL'. This specifies a distinct action (posting a reel) and resource (Instagram) and distinguishes it from sibling tools like post_photo or post_story_video.

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 provides clear usage context by specifying technical requirements: video must be 9:16 aspect ratio and 3-90 seconds long. This helps the agent decide if the tool is appropriate for a given video. It does not explicitly mention alternatives, but the context is clear enough to infer when this tool is relevant.

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