Save Design Export

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

Annotations already declare a write (readOnlyHint=false), idempotent and non-destructive; the description goes beyond them by specifying exactly what is serialized (layout, paint, text, variables, styles, components, interactions, SVGs, masked/rotated renders, image fills, 2x preview) and that the default target is the selection. It omits overwrite/error behavior, but idempotentHint covers much of that risk.

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?

Two sentences, verb front-loaded, with the content enumeration kept as a single clause list rather than separate sentences. Nothing is redundant 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?

With no output schema the description carries the return burden, and it does so by describing the written payload in detail. It does not state whether an existing file is overwritten or whether the directory must pre-exist, but for a 3-param, all-optional, idempotent write tool this is close to sufficient.

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 baseline is 3. The description restates the two defaults (selection, data folder) that the schema parameters already document, adding no new syntax, path-creation, or fileKey caveats beyond what is already present.

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: 'Write a full design export of a node ... to a JSON file', and immediately enumerates the export's contents. It is clearly distinguishable from siblings like import_design_export (the inverse) and get_design_context without opening a schema.

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?

'Use it to hand a frame to a build script' gives a concrete use context and the implicit default (current selection). It stops short of naming when NOT to use it or pointing to alternatives such as import_design_export or get_design_context, so it is clear but not exhaustive.

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