Cushion is a free, open-source, local-first Markdown workspace with a built-in AI sidebar for notes, documents, PDFs, diagrams, and local dictation.
It’s ideal for writers, researchers, and developers who want AI assistance in their notes without subscribing to a separate service.
Obsidian handles Markdown well but lacks native AI integration, while Cursor has an AI sidebar but is built for code, not prose.
Cushion merges both capabilities into a single app. The AI sidebar runs on OpenCode and supports MCP servers, skills, agents, and multiple models auto-discovered at runtime.
Features
- Renders markdown as rich text in a CodeMirror 6 editor that hides syntax until you edit.
- Opens an AI chat sidebar through OpenCode with skills, agents, MCP servers, and automatic model discovery.
- Converts speech to text on device through Sherpa ONNX.
- Opens Excalidraw drawings, PDFs, and KaTeX math in the same workspace.
- Reviews note edits as inline diffs that you can accept or reject in the editor.
- Exports documents to DOCX, EPUB, HTML, ODT, LaTeX, and plain text through Pandoc.
- Splits the editor into two panes for side-by-side work.
Use Cases
- Draft long-form notes and ask the AI sidebar to rewrite sections, explain passages, or suggest edits in the same file.
- Read research PDFs, highlight key passages, and ask the AI for summaries or explanations next to the document.
- Dictate meeting notes, outlines, or rough drafts on a local machine that keeps speech processing on device.
- Create flowcharts or architecture sketches in Excalidraw and keep them beside the notes that explain them.
- Add MCP servers, skills, and agents for custom research or writing workflows inside the AI sidebar.
Key workflows
PDF Q&A: Open a PDF file inside Cushion, highlight the text you want to discuss, then ask the AI sidebar a question. The sidebar returns summaries, explanations, or comparisons based on the document content.
Diagram generation: Open or create a note, type a description of the diagram you need, then prompt the AI to generate it as an Excalidraw drawing. The result appears inline in your document.
AI Review: Activate AI Review from the sidebar. The AI proposes edits as inline diffs. Use the accept or reject controls to apply changes one at a time.
Local dictation: Activate the Whisper/Sherpa ONNX dictation feature and speak into your microphone. The transcript appears in the current note. Audio processing runs on your local machine.
MCP and skills: Open the Tools panel in the AI sidebar to connect MCP servers or add skills. Once connected, the AI can call those tools during a chat session.
Pros
- No subscription fees.
- Local-first architecture.
- Multi-model support.
Cons
- Mac users must build from source.
- Beta status.
Related Resources
- OpenCode: The AI backend that powers Cushion’s chat sidebar.
- Sherpa ONNX: The local speech recognition engine Cushion uses for dictation.
- Excalidraw: The open-source diagramming tool embedded in Cushion.
- Obsidian: A mature markdown workspace that Cushion draws inspiration from.
- notebooklm-py: The library that makes the NotebookLM integration in Cushion possible.
FAQs
Q: Does Cushion require a paid AI subscription?
A: No. The AI sidebar runs on OpenCode, which auto-discovers models available on your system or through API keys you already have.
Q: Does Cushion send my notes or audio to the cloud?
A: Local models stay local, and remote API models send prompts to their respective providers.
Q: How do I add AI models to Cushion?
A: Cushion uses OpenCode for its AI backend. OpenCode auto-discovers models at runtime based on the API keys and local model configurations you have set up in your environment.
