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

Annotations already indicate mutating (readOnlyHint=false) and non-idempotent behavior. The description adds meaningful context: it uses the 'real HyperFrames render worker', produces an MP4, and instructs to use get_editor_run to track the result. This goes beyond the annotations by clarifying the asynchronous follow-up workflow.

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 sentences, front-loaded with the core action and concise follow-up guidance. Every word earns its place; no fluff or repetition.

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 one-parameter tool with no output schema, the description is largely complete: it states the action, output format, and follow-up tool. However, it does not explicitly state prerequisites (e.g., that the project must already exist) or what the render returns (though the get_editor_run reference implies a run ID). Minor gaps keep it from a 5.

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 has a single required project_id with no description (0% schema coverage). The description says 'your current persistent Switch Editor project,' which implies project_id refers to that project, but it does not explicitly state 'project_id is the ID of the current persistent project.' The meaning is inferable but not explicitly mapped.

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: 'Render your current persistent Switch Editor project as an MP4' with a specific verb (Render), a resource (project), and an output (MP4). This distinguishes it from siblings like get_editor_run (which tracks runs) and create_editor_project (which creates projects).

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: render the current persistent project and then 'Use get_editor_run to follow it to playback and download.' While it names the follow-up tool, it does not explicitly mention when not to use this tool or alternative render methods, but as the only render tool, that is less critical.

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