Add shape

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

Beyond the annotations, it explains that a new shape group is created, existing groups are preserved, coordinate positions are layer-relative, new layers are centered in the comp, and it returns the layer and new group. It does not elaborate on non-idempotency or permission requirements, but the annotations already establish the mutation and safety profile.

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 front-loaded with the core operation, then adds coordinate semantics, return values, and the mask alternative in a compact sequence. Every sentence contributes actionable information without redundant restatement of schema defaults.

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 17-parameter mutation tool with high schema coverage and no output schema, the description covers layer targeting, coordinate behavior, return values, and the key alternative tool. Nothing essential about invoking it correctly appears to be missing.

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 schema already documents 94% of the 17 parameters, so the baseline is 3. The description adds useful semantic context about coordinate positioning relative to the layer and the comp-center convention for new layers, which is not fully captured by the schema alone.

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?

It names the specific action (draw a shape) and enumerates the shape types, fill/stroke support, and whether it creates a new shape layer or adds to an existing one. It also explicitly distinguishes itself from ae_add_mask for cut-out operations.

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 states when to use an existing layer versus creating a new one, notes that existing groups are kept, and names ae_add_mask as the alternative for cutting out part of a layer. This gives clear routing guidance without leaving the agent to infer alternatives.

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