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

The readOnlyHint=false annotation already signals mutation. The description adds that 'cut clears the transition' and gives duration guidance for dissolve, but it does not explain permissions, reversibility, what happens to an existing transition, or response 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 concise, front-loaded, and free of filler. The parenthetical clarifies direction immediately, and the semicolon-separated guidance is efficiently packed.

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 mutation tool with no output schema, minimal annotations, and low schema coverage, the description is too thin. It omits what setting a transition overwrites, how required IDs relate to the target scene, and details for most transition types.

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 only 20%, so the description should compensate. It adds meaning for direction (in/out) and a few type values (dissolve, fade, cut), but leaves most of the 12 enum values, scene_id, and duration_ms under-explained.

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 uses a specific verb and resource: 'Set a scene's transition.' It also clarifies that direction means entering versus leaving. However, it does not explicitly distinguish this from sibling tools such as studio.update_scene, which could also affect scene properties.

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 gives useful guidance for choosing among transition types: dissolve for connection, fade for scene breaks, cut clears the transition. But it does not state when to use this tool versus alternatives, nor does it mention prerequisites or exclusions.

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