setLayerExpression

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

Without annotations, the description carries full responsibility for behavioral disclosure. It does not mention whether the expression overwrites an existing one, what happens with invalid expressions, or whether properties must support expressions. This lack of context is a significant gap for a mutation 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?

The description is a single clear sentence with no redundancy. It gets directly to the point, though it could be enriched with more context. It earns its place but is minimal.

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?

The tool has four required parameters, no output schema, and no annotations. The description only states the core action, lacking details about return values, error conditions, prerequisites, or side effects. This is insufficient for a tool that modifies layer properties.

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?

The input schema provides descriptions for all four parameters, so the baseline is 3. The tool description adds no additional parameter semantics beyond the schema, but since coverage is 100%, the schema carries the burden.

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' and identifies the resource 'expression on a layer property', which clearly differentiates it from sibling tools like setLayerKeyframe and setEffectKeyframes that deal with keyframes. This is a clear and distinct purpose.

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 tool versus alternatives like setLayerKeyframe or run-script. The description simply states the action without contextual usage scenarios or exclusions.

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