Set Effects

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

Annotations provide idempotentHint and openWorldHint, and the description adds scope ('shadows, blurs'). However, it does not explicitly state that the effect array is replaced wholesale, nor does it mention preconditions or failure modes. The 'set' verb implies replacement, but the description remains minimal on behavioral detail.

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 succinct, front-loaded sentences with zero filler. The first sentence states the tool's action and scope; the second gives an explicit alternative. Every word earns its place.

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?

Given the very rich input schema and the presence of an output schema, the description covers core purpose and usage guidance without redundant details. The only minor gap is not explicitly noting that existing effects are overwritten, though this is strongly implied by the verb 'set'.

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 has exhaustive descriptions for all three parameters, including nested effect variants, defaults, and constraints (100% coverage). The description adds no extra parameter-level information, so the baseline score of 3 applies.

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 clearly identifies the target resource ('a node's effect array') and scope ('shadows, blurs'). It also distinguishes this tool from siblings by explicitly naming node_apply_style as the alternative for shared effect styles.

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 provides explicit when-to-use guidance: use this tool for direct effect arrays, and points to node_apply_style as the alternative for shared styles. This clear exclusion and alternative naming makes tool selection straightforward.

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