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

With no annotations, the description carries the full burden. It discloses that it 'processes in the browser' and uses more credits per run, which is useful context. However, it omits critical behavioral details such as what happens to the original video, supported file types, or whether the operation requires user interaction in the browser, leaving noticeable 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 purpose is front-loaded in a clear single sentence, but the remaining five sentences are dedicated to credit/pricing details. While relevant, this is disproportionately verbose for a tool definition and could be condensed to one or two sentences without losing value.

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?

The tool has an empty input schema, no output schema, and no annotations, yet the description does not explain how the agent is supposed to provide the video/audio inputs or what the tool returns. It covers purpose and credit constraints but lacks essential operational context, making it incomplete for an agent to invoke 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 input schema has zero parameters, so the baseline is 4. The description adds no parameter-specific meaning because there are none to explain, but it does not need to compensate for schema gaps since there are no parameters.

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 opens with a specific verb+resource: 'Add Audio to Video — Replace or add audio track to a video file.' This clearly states the tool's function and distinguishes it from sibling tools like mute, normalize audio, or extracting subtitles.

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?

No guidance is given on when to use this tool versus alternatives. The description focuses on credit/workspace details but does not mention criteria for selecting this tool over other video/audio editing tools, nor does it provide exclusions or alternative recommendations.

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