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

There are no annotations, so the description carries the burden of showing this is a read-only inspection operation. It does so through 'drill-in', 'Returns', and 'about to mutate' as a future step, and it names the exact categories of data returned. It does not explicitly state 'does not modify the project' or mention auth/rate-limit caveats, which is a minor gap.

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 three sentences with no filler: it front-loads the core purpose, then the return payload, then the invocation constraint. Every sentence earns its place and it does not repeat the schema property definitions.

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?

Since no output schema is provided, the description's enumeration of returned content is essential and largely sufficient. It also explains where elementIds come from and how many to pass. However, the exact output shape—whether a map keyed by elementId or a flat array—is not specified, leaving a small completeness gap.

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?

Both parameters are already fully documented in the schema, so this starts at a baseline of 3. The description adds useful selection guidance for elementIds: read them from describe_video and pull detail only for the layers about to be mutated. It adds nothing beyond the schema for projectId.

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 what the tool does: 'Full per-element drill-in' that 'Returns each named element's COMPLETE record', and it enumerates the returned content including animation tracks, keyframes, colour/fill tracks, loop modes, and style. It also distinguishes itself from describe_video and the mutating sibling tools by calling itself the 'open this layer' half of the browser and framing mutation as a later step.

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 an explicit workflow: pass the elementIds read from describe_video, and inspect only the handful of layers you are about to mutate, not the whole project. This tells the agent when to call the tool, where to get inputs, and how to limit scope, which is strong usage guidance.

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