ae_setTrackMatte

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

Annotations already declare this as a non-readonly but non-destructive, non-open-world mutation, so the safety profile is covered. The description usefully adds AE-specific behavioral context about layer stacking ('image on top'), but it does not say what happens to an existing matte, what 'none' does (presumably clears the matte), or whether the change is undoable.

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?

Two short sentences, front-loaded with the 'After Effects:' domain tag and the core action, with zero filler. The example is compact but its telegraphic phrasing slightly compresses rather than clarifies.

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 4-parameter mutation with no output schema, the description covers purpose, matte modes, and one concrete scenario, which is close to sufficient. The remaining gap is default behavior when the optional `matteLayer`/`type` are omitted, and confirmation of how a matte is removed.

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 coverage is 75%, so most parameters are already documented, and the description only echoes them by naming `matteLayer`, `layer`, and listing the enum values without explaining alpha vs luma or inverted variants. `compositionName` is left entirely to the schema, and the fact that `matteLayer` and `type` are optional with unstated defaults is not addressed.

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: assign `matteLayer` as the track matte for `layer`, scoped to After Effects. The enumerated matte types make the operation concrete, and it is distinguishable from neighboring layer-relationship tools like `ae_parentLayer` or `ae_setBlendingMode`, though it never names those siblings explicitly.

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 example 'Image on top, shape as alpha matte = clip image into shape' gives an implied use case and hints at the required stacking order. There is no explicit when-to-use/when-not guidance, no mention of alternatives for similar visual results (blending modes, masks), and no prerequisites such as the matte layer needing to sit above the target layer.

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