obs_preview_scene

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

With no annotations, the description carries full weight and reveals important non-obvious behaviors: failure code 506 and its translation, the limit that staging does not guarantee network feeds, that staged scenes are not frozen, and that preview/program swap after transition. This goes far beyond a basic read/set statement.

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 opens with the core purpose, then uses a clearly labeled 'TRAPS' section to list non-obvious behaviors in an easy-to-scan way. Despite length, each item adds real operational value and no sentence has plain, unnecessary filler.

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 is parameter-simple but operationally nuanced, and this description covers studio mode prerequisites, failure codes, cross-tool workflow, network source caveats, and the dynamic nature of preview. Given that no output schema exists, the description provides complete enough context for an agent to decide and invoke the tool 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 single parameter sceneName is already fully documented in the schema ('Omit to just read. Exact scene name from obs_list_scenes'), and the description mainly reinforces 'omit' vs 'set' in prose without adding new parameter-level details. Schema coverage is 100%, so baseline 3 is appropriate.

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 identifies a specific verb+resource: 'Read or set the scene currently sitting in PREVIEW' and clarifies it is staged, not on air. It explicitly distinguishes itself from the scene-change workflow by calling it 'the safe half of a scene change' and contrasting it with obs_studio_transition.

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?

It includes named alternatives and a required workflow: 'Stage here, screenshot the scene by name... then cut with obs_studio_transition.' It also names obs_studio_mode as the fix when studio mode is off and warns about relying on staged scenes without screenshot confirmation, which is strong when-to-use and when-not-to-use guidance.

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