create_frame

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

With no annotations, the description carries the full burden and does disclose a genuinely non-obvious behavior: Figma's native white fill is cleared so containers default to transparent, plus the auto-layout sizing caveat. It omits return values, coordinate space for root frames, and permissions.

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?

Front-loads the create action and default-fill behavior before the conditional guidance; every sentence carries usable information. Slightly dense but no obvious filler.

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 creation tool with no annotations and no output schema, the description covers fills and auto-layout nesting well but leaves several parameters (r/g/b, opacity, name, keepDefaultFill semantics) and any return behavior unaddressed.

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 coverage is only 53%, and the description compensates by explaining fillHex, x/y, width/height, parentNodeId, index, and layoutSizing usage. However the unexplained r/g/b parameters are never addressed anywhere, leaving a real gap.

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?

States a specific verb+resource ('Create a new frame') and immediately characterizes its default behavior. It doesn't explicitly differentiate from close siblings like create_rectangle, create_section, or group_nodes, so it's clear but not sibling-routing.

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?

Gives concrete conditional guidance: pass fillHex only for visible surfaces, and omit x/y and width/height when nesting into auto layout. It doesn't name alternative tools or state exclusions, but the when-to-omit rules are actionable.

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