Execute arbitrary ExtendScript JavaScript directly inside Adobe After Effects with full DOM access to automate compositions, layers, effects, and project tasks.
Execute arbitrary ExtendScript JavaScript code directly inside Adobe After Effects with full DOM access
| Name | Required | Description | Default |
|---|---|---|---|
| script | Yes | The ExtendScript JavaScript code to execute | |
| description | No | Optional brief description of what the script does |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden, and it discloses only capability ('arbitrary' code, 'full DOM access'). It says nothing about destructive potential, lack of rollback, whether scripts run synchronously, error handling, or security constraints — critical omissions for an arbitrary-code-execution tool.
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?
A single front-loaded sentence with zero filler; the verb and the capability scope come first. Nothing redundant or padding.
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 high-complexity, high-risk arbitrary-code tool with no annotations and no output schema, the description is too thin. It omits risk profile, execution semantics, and any notion of what the call produces or how failures surface.
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% with only two self-explanatory parameters (script, description), so the schema already does the heavy lifting. The description adds no format, language, or syntax guidance beyond what the schema provides, warranting the baseline 3.
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 states a specific verb (Execute) and resource (arbitrary ExtendScript JavaScript code) with the scope qualifier 'directly inside Adobe After Effects with full DOM access.' An agent can tell this is a generic code-execution escape hatch, distinct from the specific effect/layer/composition siblings, though no sibling is named 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?
There is no guidance on when to use this versus the ~50 specific sibling tools (e.g., applyEffect, setLayerProperties). It never states the intended use case ('operations not covered by dedicated tools') or any when-not condition, leaving the agent to infer that this is the fallback for uncovered operations.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.