Render a Kodecz video

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

Annotations already declare it is not read-only, is idempotent and non-destructive, and the description usefully adds the GPU/NVENC-vs-CPU/x264 selection rule and the return shape ('JSON result line'). However, it never says what happens to an existing `output` file, whether the render is long-running, or what the result line contains — notable gaps for a file-writing mutation.

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?

Two tight sentences: the action and encoding rule come first, the return value and prerequisite follow. Zero filler, and the prerequisite is placed where it will be read before invocation.

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?

With 8 parameters, a mutation profile, and no output schema, the description supplies the key missing pieces: encoding fallback behavior, the return format, and the `check`-first requirement. Overwrite semantics and expected runtime remain unstated, which keeps it from being complete.

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%, so all 8 parameters are already documented in the schema, including the GPU-only constraint on `hevc` and `alpha`. The description's GPU-vs-CPU sentence largely restates the `cpu` parameter's own text, adding little beyond what the structured field already provides.

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?

States a specific verb (render) and resource (a Kodecz video folder) plus the output format (MP4) and encoder selection logic, so the agent knows exactly what happens. It does not distinguish itself from the `preview` sibling, so it falls just short of a 5.

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?

Gives an explicit prerequisite sequence ('Run `check` first'), which is actionable context an agent would otherwise miss. It offers no guidance about when to choose `preview` instead, so it is clear but not fully discriminating.

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