create_component_instance

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

No annotations are provided, so the description must carry the full burden. It states 'Create an instance' which implies a mutation, but it does not disclose what happens after creation (e.g., the node is added to the canvas, the response includes the instance ID), no mention of permissions, side effects, or undoability. This is insufficient 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 extremely concise, consisting of two sentences that deliver the essential information without any fluff. Every sentence adds value, and the key distinction is front-loaded in the first sentence.

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 that there are 5 parameters (2 required), no output schema, and no annotations, the description is adequate but lacks important context. It explains how to parameterize the call but does not describe the outcome (e.g., what the response contains, how the instance appears in Figma, error conditions) or any prerequisites beyond get_local_components.

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?

All parameters are described in the schema (100% coverage), but the description adds critical context: it links componentId to the 'id' field from get_local_components and componentKey to the 'publishedKey' field, clarifying the relationship between the source function and this tool's parameters. This goes beyond the schema's individual descriptions.

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 clearly states the action: 'Create an instance of a component in Figma'. It distinguishes between local and library components by specifying which parameter to use (componentId vs componentKey) and references the source function get_local_components. This differentiates it from sibling tools like create_frame or clone_node.

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 explicitly tells when to use componentId (for local components) versus componentKey (for published library components), providing a clear conditional. However, it does not explicitly state when not to use this tool (e.g., for creating shapes or frames), but the context of the sibling tools and the Figma domain makes this clear enough.

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