obs-start-virtual-cam

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states the action ('starts') but doesn't explain what 'virtualcam output' entails, whether it requires specific permissions, if it's idempotent (e.g., no effect if already running), or what happens on failure. This is a significant gap for a mutation tool with zero annotation coverage.

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 a single, efficient sentence with no wasted words. It's front-loaded with the core action and target, making it easy to parse quickly. Every word earns its place by conveying essential information.

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 the complexity of starting a virtual camera (a mutation operation), no annotations, and no output schema, the description is incomplete. It lacks details on behavior, side effects, error conditions, or what success looks like. For a tool that likely interacts with system resources, this is inadequate.

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 0 parameters with 100% coverage, so no parameter documentation is needed. The description doesn't add parameter details, which is appropriate. Baseline is 4 for 0 parameters, as it doesn't need to compensate for any schema gaps.

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 'Starts the virtualcam output' clearly states the action (starts) and target (virtualcam output), which is a specific verb+resource combination. However, it doesn't differentiate from sibling tools like 'obs-stop-virtual-cam' or 'obs-toggle-virtual-cam' beyond the obvious start/stop distinction, making it somewhat vague about its unique role in the OBS ecosystem.

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., virtual camera setup), when not to use it (e.g., if already running), or explicit alternatives like 'obs-toggle-virtual-cam' for toggling state. This leaves the agent without context for tool selection.

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