figma-plugin-api-ruleslisted

# Figma Plugin API Rules Accumulated, field-tested knowledge of the Figma Plugin API as driven through an agent (`use_figma`-style calls). Every entry is a real case that broke exactly this way, written up as Principle / Symptom / Pattern — not a reading of the docs. Core principle: **the MCP plugin sandbox is not your desktop Figma** — fonts, library resolution, page context and multi-property writes behave differently, and many failures are *silent*. **Required companion:** your tool's own instructions for calling the Figma API must be loaded before the first call — in Claude Code that is the `figma-use` plugin skill; in other agents load the MCP resource `skill://figma/figma-use/SKILL.md`. This pack adds to that; it does not replace it. For repairing detached or missing variable bindings, also load `figma-fix-variable-bindings`. If a required skill is missing or needs a restart, say so before starting rather than guessing tooling. ## Hard rules 1. **Your tool's Figma API instructions load before the first call — always.** This pack complements them. 2. **Inspect before you mutate.** Read `componentPropertyDefinitions`, `children`, and bounding boxes *before* writing. 3. **Verify every ID that came from a prompt or a past session** with one read-only call before the first write (see `verify-variable-ids-before-write` below). Passed-in IDs are routinely off-by-N or point at a sibling. 4. **Load the topic file before the first write that uses its API — match on the code y