Scene Render Preview

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

Goes well beyond the readOnlyHint/idempotentHint annotations: it discloses that the camera flag switch is instantaneous but NOT undoable, that the net state is restored on every path including failure, that the timeline may visibly jump, that no viewer window opens, and that only a killed process can skip the restore. This is exactly the kind of side-effect detail annotations cannot carry.

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 one-line purpose is front-loaded, followed by a numbered disclosure list where each item carries distinct information. The list is long but nearly every entry earns its place; a small amount of trimming is possible but nothing is obviously wasteful.

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 no output schema and a fairly complex side-effecting operation, the description covers the session requirement, the state-restoration contract, and the failure behavior thoroughly. It stops short of describing the returned image/metadata payload, though it does point at 'the returned metadata' as the source of truth for size.

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 parameter meaning is already fully documented by the schema, establishing a baseline of 3. The description adds no parameter semantics of its own and in fact references a 'viewer=False' option that does not appear in the input schema, which is mildly confusing.

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 and resource ('Single-frame playblast preview from a camera') with the scope qualifier 'clean, no HUD', so an agent knows exactly what artifact is produced. It does not, however, differentiate itself from the closely named sibling scene_viewport_snapshot, which is the main ambiguity an agent would face.

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 'GUI sessions only - headless sessions get a structured gui_session_required error' line is a genuine when-not condition, telling the agent the call will fail in headless contexts. It stops short of naming an alternative tool for the headless case, so it is clear context rather than full routing guidance.

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