Rive MCP server

rive-mcp

Create, edit, inspect, render and live-preview Rive (.riv) animations from Claude — no Rive editor, no cloud, no subscription.

日本語 README はこちら

rive-mcp is a free MCP (Model Context Protocol) server that gives Claude (or any MCP client) full control over .riv files. Unlike the official Rive MCP (which requires the editor running) or paid third-party servers, it works with nothing but a .riv file — and it can even build .riv files from scratch by serializing the binary format directly.

Rendering runs the official Rive runtime (@rive-app/canvas-advanced WASM) inside headless Chromium, so what you see is exactly what ships.

This animation was generated entirely by riv_create — no Rive editor involved.

Highlights

• Generate .riv from JSON — shapes, gradients, embedded PNGs, text, bones + skinning, IK, mesh deformation, keyframe animation with easing, multi-layer state machines, listeners, events, physics baking, particles, embedded audio (WAV/MP3/FLAC) fired from the timeline or a state machine
• Pro-quality by construction — 28 semantic motion presets (pop-in, staggered rise-in, breathing, stagger-in, parallax-drift, shimmer, …) with professionally tuned amplitudes/easings, an OKLCH design-token generator (rivdesigntokens), motion-quality lint rules (robotic linear movement, teleports, missing stagger), and a one-call critique loop (riv_critique: frames + objective metrics + scoring checklist)
• Real vector art pipeline — import SVG (Figma/Illustrator/Iconify, or npm SVG sets like @twemoji/svg when offline) as true bezier paths (rivimportsvg, rivassetsearch), decompile existing .riv files into editable specs including gradients, blend modes and hand-tuned animation tracks (riv_decompile), plus trim paths (draw-on), clipping masks, blend modes (multiply shadows, screen glows), follow-path motion, solos and detached bezier handles in the scene spec
• Losslessly edit existing .riv — change any property, swap text, delete subtrees (references auto-remapped); round-trip verified pixel-perfect
• Local web Studio — Rive-editor-style 3-pane UI (hierarchy / canvas with click-select & drag / inspector / timeline) with hot reload; edits apply live. Also includes a bezier curve editor for hand-tuning keyframe easing (drag control points, hold/linear/cubic switching, 10 one-click presets), a state machine graph view (node graph of layers/states/transitions with lint findings and live-playback state highlighting), and an onion skin overlay (0-5 surrounding frames) for checking motion at a glance
• Studio keeps growing — drag-and-drop image replacement for embedded assets (lossless swap), multi-artboard tabs, named snapshot save/restore/delete, dope-sheet marquee/Shift-click multi-select with grouped drag and Ctrl+C/V copy-paste, and a bone overlay with FK drag-to-pose that bakes straight to a keyframe
• Human ⇄ AI loop — a two-way Agent chat in the Studio: you type feedback (with the current selection/artboard/animation/time attached), the AI picks it up via rivstudionotes, fixes the file, and replies into the same thread; your browser updates instantly
• Auto-rig characters — one call turns a character PNG into a rigged .riv with cutout parts, bone-skinned head mesh, eye blink, idle/happy animations and a state machine
• Data binding & pipeline tooling — rivinspect decodes ViewModel definitions, instances (with resolved values), enums, converters and bind wiring — data binding inspection that few tools support yet; rivbatch_render exports many files × formats in one glob-aware call for CI, and

Shortened. The full README is on GitHub.