render_screen

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

With no annotations provided, the description carries full burden for behavioral disclosure. It explains the default trueGeometry mode, mentions the legacy painter option, and instructs to open the file rather than redraw. It does not cover all edge cases but adds significant 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 four sentences that pack essential information without fluff. Every sentence earns its place: purpose, recommended usage, default behavior, and alternative tool. No wasted words.

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 the complexity of the tool with many parameters and no output schema, the description covers the core workflow and directs to an alternative for safe file export. It lacks details on fallback behavior when outputPath is not set, but overall it is sufficiently complete.

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 100%, so the schema already documents each parameter. The description adds value by explaining the workflow (e.g., 'Prefer options.outputPath') and providing context for defaults like trueGeometry using baked Figma geometry. This goes beyond the schema's repetitive 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 starts with a specific verb+resource: 'Screenshot ground truth of a node subtree.' It clearly distinguishes this tool from siblings like export_asset_pack by directing that tool for agent-safe files. The purpose is unambiguous.

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 advises to 'Prefer options.outputPath and OPEN the PNG on disk — do not redraw' and to use export_asset_pack for agent-safe files, providing clear context for when to use this tool versus alternatives. It does not explicitly state when not to use it, but the guidance is sufficient.

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