set_layout_grids

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

With no annotations, the description carries the full burden and handles it well: it discloses that Figma rejects sectionSize under STRETCH and offset under CENTER, and that the bridge silently drops those keys and strips undeclared keys rather than failing. That silent-failure behavior is exactly the kind of trait an agent needs. It does not describe return values, but none are needed without an output schema.

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-loaded with the core action, then the input shape, then the edge-case behavior. Despite the dense grid spec, each sentence earns its place given the empty schema. Slightly dense but well ordered.

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 mutation tool with no annotations and no output schema, the input contract and error handling are well covered. The notable gap is replace-vs-append semantics: 'Set' could mean overwrite existing layout grids or add to them, and nothing states the effect on prior grids or the response.

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 0% and layoutGrids is an untyped array, so the description compensates heavily by enumerating grid shapes, the pattern and alignment enums, and optional keys (gutterSize, count, sectionSize, visible, color). It adds substantial meaning beyond the bare schema, though frameId semantics remain implicit.

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 and resource: 'Set layout grids (layout guides) on a frame.' The parenthetical clarifies the Figma concept. However, it does not distinguish itself from siblings like set_grid_layout, generate_grid, or set_grid_child_position, which an agent must disambiguate from the name alone.

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?

No explicit when-to-use, when-not-to-use, or alternative-tool guidance. The description explains input validation behavior but never addresses tool selection against the many grid-related siblings, leaving the agent to infer context.

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