An embedded visual workspace for Claude Code — edit Excalidraw diagrams, tldraw canvases, Markdown notes, and DuckDB tables in the browser preview pane, all linked together with [[wikilinks]].
Claude also gets MCP tools to create, query, and edit all four file types inline — including authentic PNG previews for diagrams and structured table data for DuckDB files.
| ⬡ Excalidraw | Rough hand-drawn diagrams. Claude creates and edits them via MCP tools and sees PNG previews inline. Also fully editable in the browser. |
| ◈ tldraw | Infinite canvas with a full shape library. Browser-only — no MCP tools needed, just open and draw. |
| ¶ Markdown | Full CommonMark with [[wikilinks]], ![[diagram embeds]], images, tables, code blocks, strikethrough. Frontmatter panel, note style/color picker. |
| 🦆 DuckDB | Real embedded analytical tables. Claude creates schemas, writes rows, runs SQL queries, and creates dynamic views via MCP tools. Embed live previews with ![[name.duckdb]]. Click column headers to sort. Click the filename to rename in place. |
Drop in a .pdf file and open it in the browser — page-by-page viewer with zoom. |
|
| 📊 CSV | .csv files open as read-only tables with the same column-sort UI as DuckDB. |
All editors are live-synced via SSE — Claude's edits appear in the browser immediately and vice versa.
Registers the MCP server and /editor-start · /editor-stop slash commands for every project:
npx embedded-editor-for-claude-code init --globalRestart Claude Code, then use the slash commands in any project:
/editor-start ← starts the viewer and opens it in the preview pane
/editor-stop ← shuts it down
Adds a full Excalidraw element reference to CLAUDE.md so Claude knows the diagram API without being told. Run inside the project you want to set up:
cd your-project
npx embedded-editor-for-claude-code initnpx embedded-editor-for-claude-code@latest init --globalRe-run
initafter upgrading to refresh the API reference inCLAUDE.md.
If you prefer not to use init, add the MCP server directly:
claude mcp add --transport stdio embedded-editor -- npx -y embedded-editor-for-claude-codeDesktop app users: installation always requires a terminal step. Run any command above in a terminal, then switch to the desktop app — it picks up the configuration automatically without a restart.
"Draw an architecture diagram of this service"
"Sketch the auth flow as a sequence diagram"
"Add a database node to the existing diagram"
Claude calls the MCP tools and returns PNG previews inline as it builds the diagram.
"Create a table tracking sprint velocity — story points planned vs delivered"
Claude creates velocity.duckdb, defines the schema, and seeds it with rows. Open the file in the browser and you get a full table viewer with a slideout SQL query pane:
┌─────────────────────────────────────────────────────────────────┐
│ velocity.duckdb · 4 rows │ ⌘ Query │ ≡ Table │ ⊞ Cards │ ↓ │
├──────────┬───────────────────────────────────────────────────────┤
│ SQL·QUERY│ sprint │ planned │ delivered │ pct │ status │
│ ├──────────┼─────────┼───────────┼───────┼─────────────│
│ SELECT │ 1 │ 34 │ 29 │ 85.3% │ ⚠ Below │
│ sprint,│ 2 │ 40 │ 38 │ 95.0% │ ✓ │
│ ... │ 3 │ 36 │ 36 │ 100% │ ✓ │
│ │ 4 │ 42 │ 31 │ 73.8% │ ⚠ Below │
│ ▶ Run ⌘↵ │ │
└──────────┴───────────────────────────────────────────────────────┘
Click ⌘ Query to slide the SQL editor open. Write any SQL and hit ⌘↵ — results replace the table view instantly. Switch to ⊞ Cards for a Kanban-style board that groups rows by any column (auto-detected from status, state, stage, etc.) with drag-to-regroup.
Click any column header to sort (click again to reverse). The header turns amber and shows ▲/▼. Click the filename in the toolbar to rename the file in place — the tab bar, sidebar, and all wikilinks update automatically.
The toolbar also shows "updated Xm ago" — a timestamp updated after every write_rows call, equivalent to Jupyter's "last run" indicator.
Embed a live preview in any note with ![[velocity.duckdb]] — it renders an inline table that updates whenever the data changes. The embed supports the same column sort.
Excalidraw diagrams
| Tool | What it does |
|---|---|
list_diagrams |
List all .excalidraw files |
create_diagram |
Create a blank diagram; returns PNG preview |
read_diagram |
Return current JSON + PNG |
write_diagram |
Replace elements; returns PNG |
append_elements |
Add elements to existing diagram; returns PNG |
delete_diagram |
Delete a diagram file |
Markdown notes
| Tool | What it does |
|---|---|
list_notes |
List all .md notes |
create_note |
Create a blank note |
read_note |
Read note content |
write_note |
Write (replace) note content |
delete_note |
Delete a note |
DuckDB tables
| Tool | What it does |
|---|---|
list_tables |
List all .duckdb files |
create_table |
Create a new DuckDB file with an optional schema |
read_table |
Read rows from the first user table (returns markdown) |
write_rows |
Upsert rows into a table (batched — all rows in one SQL statement) |
delete_rows |
Delete rows matching a WHERE clause |
query_table |
Run arbitrary SQL; optional save_as inserts results into another table |
create_view |
Create a named DuckDB VIEW — a saved SQL query that re-executes dynamically on every read. Any column whose values match workspace file names gets a companion _name column with [[wikilinks]]; the browser renders those cells as clickable navigation links. |
Workspace
| Tool | What it does |
|---|---|
list_workspace |
List all files grouped by type in one call (diagrams, notes, tldraw, tables) |
rename_file |
Rename a file and rewrite all [[wikilinks]] |
get_backlinks |
Find all files that link to a given file |
list_history |
List saved snapshots for a diagram |
restore_snapshot |
Restore a diagram to a saved version |
list_tldraw |
List tldraw canvas files |
read_tldraw |
Read tldraw canvas JSON |
- Claude calls
write_diagramwith Excalidraw JSON elements - The server writes the
.excalidrawfile - Excalidraw's
exportToSvgruns in a jsdom shim — authentic SVG with rough.js strokes, hachure fills, real arrowheads @resvg/resvg-jsrasterizes to PNG- Returns
{type: "image", mimeType: "image/png", data: <base64>}— Claude Code renders it inline
- File browser — sidebar lists all
.excalidraw,.tldraw,.md,.duckdb,.pdf, and.csvfiles; filter by type - Wikilinks —
[[filename]]in any editor navigates to that file as a new tab - Diagram embeds —
![[diagram.excalidraw]]in Markdown renders the diagram inline in preview - Image embeds —
works with local files; the server serves them from the project directory - Backlinks — see which files link to the current one
- Version history — last 30 versions auto-saved; browse and restore from the history panel (
⟳) - Live rename — renaming rewrites all
[[wikilinks]]across the project - Live sync — SSE events push changes to all open tabs instantly
- Light/dark — follows your OS preference
- Note style picker — font style (Serif · Sans · Literary · Compact · Mono) and color profile (Auto · Sepia · Paper · Night · Forest) selectors in the Markdown toolbar; each setting is independent and persists across sessions
- Frontmatter panel — YAML front matter in notes renders as a collapsible property panel; dates, URLs, and booleans get styled display
- External links — because the preview pane only allows
localhostnavigation, clicking any external link copies its URL to the clipboard (a "link copied" toast confirms it) - Drag-to-reorder — grab handles appear on hover for paragraphs, table rows, list items, headings (with their sections), and whole tables; drag to reorder
- Column sort — click any column header in DuckDB or CSV views to sort asc/desc (▲/▼); click again to reverse; numeric values sort numerically
- Inline rename — click the filename in a DuckDB tab or embed header to rename it in place; all wikilinks update via the server
In the Markdown note editor, type / at the start of a line to open the command palette:
| Command | What it does |
|---|---|
/diagram [description] |
Creates a new Excalidraw diagram, embeds it as ![[name.excalidraw]], and pre-fills the prompt bar with your description so Claude populates it |
/canvas [description] |
Creates a new tldraw canvas and embeds it as ![[name.tldraw]] |
/note [description] |
Creates a new linked Markdown note, embeds it as [[name]], and pre-fills the prompt bar for Claude to write its content |
/table [description] |
Creates a new DuckDB table file with a slug-based name derived from the description (e.g. /table sprint velocity → sprint-velocity-a3f.duckdb), embeds it, and pre-fills the prompt bar so Claude defines the schema |
/query [description] |
Creates a new DuckDB file as a query result target with a slug-based name, embeds it, and pre-fills Claude to write the query SQL |
/link |
Opens a searchable picker of all existing files and inserts a wikilink |
How it works:
- Type
/diagram(or/dto narrow) — the palette shows matching commands - Press
Spaceand type a description — the option updates to show your text - Press
TaborEnterto accept — the file is created instantly, the slash command is replaced with the wikilink embed, and the prompt bar below is pre-filled with your description ready to send to Claude
Example: typing /diagram show the auth flow then pressing Tab creates diagram-abc123.excalidraw, inserts ![[diagram-abc123.excalidraw]] in the note, and pre-fills:
show the auth flow
Diagram file: [[diagram-abc123.excalidraw]] (already created). Use the write_diagram MCP tool to populate it.
Copy that into Claude and it draws the diagram directly into the linked file.
![[architecture.excalidraw]]
![[architecture.tldraw]]
Running npx embedded-editor-for-claude-code init writes a complete Excalidraw element reference into your CLAUDE.md, including:
- All element types (
rectangle,ellipse,diamond,arrow,text, …) - Every valid prop value (colors, fill styles, roughness levels, stroke styles)
- Arrow binding syntax
- Copy-pasteable minimal examples
The guide is stamped with the exact package versions it was generated from. Re-run init after upgrading embedded-editor to refresh it.
- Node.js 18+
@resvg/resvg-js— prebuilt binaries for macOS (arm64/x64), Linux (x64/arm64), Windows (x64). No compilation needed on these platforms.
git clone https://github.com/1vav/embedded-editor-for-claude-code.git
cd embedded-editor-for-claude-code
npm install
npm run build # generate vendor/ bundles
# Rebuild after changing src/viewer/entry.jsx
node scripts/build-viewer-bundle.mjs
# Rebuild after bumping @excalidraw/excalidraw
node scripts/build-excalidraw-bundle.mjs
# Smoke test (MCP stdio protocol happy path)
node scripts/smoke-stdio.mjsSee CONTRIBUTING.md for full contribution guidelines.
MIT — see LICENSE