Add UI Component

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

Beyond the annotations (all false), the description discloses that the component will appear in the client dashboard in real-time, a key behavioral detail. It also lists all component types and their variants, providing context on what will be created. It does not cover error conditions or prerequisites, but adds meaningful transparency.

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 longer than minimal, but it is well-structured with clear sections for component types, variants, and arguments. The first sentence states the core purpose, and the examples are useful, so every part 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?

The tool has no output schema, and the description does not explain return values, which is a gap. However, it provides extensive guidance on all inputs, available types, variants, and examples. It lacks some context such as whether parent_id must reference an existing component, but overall it is sufficiently complete for an add operation.

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?

Although the schema covers all parameters, the description adds significant value by enumerating each component type and mapping specific variants to major types. The two concrete examples show how to structure props and variant arguments, making parameter usage much clearer.

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 'Add a UI component to the design canvas' with a specific verb and object, plus the real-time dashboard effect. It distinguishes from siblings like design_update_component and design_remove_component by focusing on the addition of new components.

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 clearly implies this is for adding new components, and the comprehensive type list helps the agent understand when to use it. However, it does not explicitly mention alternatives such as design_update_component for modifications or design_remove_component for deletions, so it falls short of a 5.

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