set_opacity

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

Discloses that opacity 0 still renders/exports/hit-tests and returns { ok, nodeId }, adding context beyond annotations which only indicate non-readonly and non-destructive.

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 sentences front-load the main action, provide key details, alternatives, and return value without waste.

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 simple tool with two params, description covers purpose, behavior, return, and disambiguation from siblings, leaving no gaps.

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 covers parameters with descriptions, but description adds semantic context: 'layer opacity' and its multiplicative effect with fill/stroke alpha, enhancing understanding of the opacity parameter.

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?

Clearly states 'Set a node's layer opacity' with range 0-1, and distinguishes from set_visible and delete_nodes by explaining behavior at opacity 0.

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?

Provides explicit guidance: when to use set_visible(false) instead of opacity 0, mentions multiplication with fill/stroke alpha, and suggests delete_nodes for removal.

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