setLayerExpression

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

The description states 'Set or remove', indicating mutation, but does not disclose side effects (e.g., overwriting existing expressions), authorization needs, or any limitations. With no annotations, the description carries the full burden of behavioral disclosure but falls short.

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 a single efficient sentence with no waste. However, it could be slightly restructured to front-load the most critical info (e.g., that an empty expressionString removes the expression), which is already in the schema.

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 no annotations, the description is incomplete. It does not explain return behavior, error conditions, or how this tool relates to siblings like setLayerKeyframe. For a 4-parameter mutation tool, more context is needed.

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% (all 4 parameters have individual descriptions). The tool description adds no extra meaning beyond the schema, so baseline 3 is appropriate.

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 'Set or remove' and identifies the resource as 'an expression for a specific layer property'. It clearly distinguishes from sibling tools like setLayerKeyframe (keyframes) and apply-effect (effects), as expressions are a distinct concept.

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?

No guidance is provided on when to use this tool versus alternatives (e.g., setLayerKeyframe for keyframes, apply-effect for effects). There is no mention of prerequisites, such as ensuring the layer exists or the property supports expressions.

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