vrma_preview

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

With no annotations, the description carries the burden of behavioral disclosure. It does disclose output formats, mode-specific behavior, the 10-second limit, and the local headless Chrome/Edge dependency, but it omits side effects such as overwriting output files, failure modes when Chrome/Edge is absent, and any return/status behavior.

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 two concise sentences that front-load the core action and resource. Every clause adds useful context: output mode, format, time/duration limits, and the headless browser dependency. There is no filler 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?

Given 10 parameters, no output schema, and no annotations, the description provides core mode semantics but leaves gaps: it doesn't explain how to use optional view/width/height params, what happens on failure, or whether output_path is overwritten. It is adequate for a simple invocation but not fully complete for a complex 10-parameter render tool.

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 already covers most parameters at 70% coverage, including mode, time_sec, duration_sec, paths, and fps. The description mostly restates these relations (PNG at time_sec, WebM max 10 seconds), adding little beyond the schema. It does not explain under-documented parameters like view, width, or height.

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 action: 'Render a VRMA animation applied to a VRM through a local headless Chrome/Edge.' It specifies the exact resources (VRMA, VRM), the output modes (PNG for image, WebM for video), and distinguishes itself from sibling inspect/snapshot tools by being the render/preview tool.

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 gives mode-specific usage: 'mode=image writes a PNG at time_sec; mode=video records a short WebM clip (max 10 seconds).' However, it does not explicitly state when to use this tool versus alternatives like vrma_inspect or vrm_snapshot, nor does it mention exclusions or prerequisites beyond the local headless browser.

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