* fix(mcp): keep diagram context valid during edits
Closes#885
* fix(mcp): replace edit_diagram time gate with content comparison
The 30s wall-clock gate rejected slow-but-correct clients (#885).
Instead of a timeout, remember the exact state-store XML the model
last saw (get_diagram / create_new_diagram / edit_diagram / page CRUD)
and reject edit_diagram only when the live browser state differs -
i.e. the user made edits the model hasn't seen yet. Slow reasoning
no longer trips the gate, while unseen manual edits still do.
* docs(mcp): align edit_diagram/get_diagram descriptions with content-based gate
The 'You MUST call get_diagram BEFORE this tool' requirement and the
'Skipping get_diagram WILL cause user's changes to be LOST' warning no
longer match server behavior: a stale edit is rejected with no side
effects, never silently applied. Describe the freshness check instead,
and direct get_diagram usage at its real purpose - learning the current
diagram content when the model doesn't already know it.
* fix(mcp): compare diagram content structurally in the edit gate
draw.io re-serialises the document when pushing state back (attribute
order, pretty-printing, regenerated diagram ids, viewport attributes,
mxfile host), so byte comparison could flag an unchanged diagram as
stale. Fingerprint what a user can actually change instead - page set,
page names, and each page's root cell tree with sorted attributes -
keeping byte equality as the fast path. A bare mxGraphModel now also
fingerprints identically to its single-page mxfile wrapping.
* fix(mcp): don't compare page names against bare mxGraphModel pushes
A bare <mxGraphModel> pushed by the embed/sync path carries no page name,
so normalizeToMxfile invents "Page-1" — falsely reading any custom page
name as a content change and re-triggering the stale rejection on every
edit. When either side of the gate comparison is a bare mxGraphModel,
fingerprint cell trees only; full-mxfile comparisons still detect renames.
* chore(mcp): bump version to 0.2.2
* chore(mcp): sync package-lock.json version to 0.2.2
---------
Co-authored-by: dayuan.jiang <jdy.toh@gmail.com>
* feat(mcp): add multi-page (mxfile) support
The MCP server's write path could only address a single drawio page even
though the underlying .drawio file format and the embedded editor both
natively support multi-page documents. A user asking for "a second page
with a CNN diagram" would hit the validator with the error
"Expected closing tag </root> but found </mxCell>" because the validator
assumed input was a bare <mxGraphModel> and could not walk past the
<mxfile><diagram>...</diagram></mxfile> wrapper.
This patch closes the gap end to end:
* New helper module `pages.ts` centralises page CRUD (normalize, parse,
list, find, add, rename, delete) so every layer agrees that the
canonical in-memory shape is always <mxfile>. normalizeToMxfile and
addPageToDoc both strip any leading <?xml ?> declaration before
embedding a fragment inside <diagram> (the declaration is only valid
at document start). addPageToDoc explicitly rejects full <mxfile>
inputs so a caller cannot accidentally nest a document inside a page.
* `xml-validation.ts` now detects an <mxfile> root and scopes the
duplicate-id check per <diagram>. The legacy regex check would
otherwise reject every multi-page doc, because cells "0" and "1"
repeat in each page's <root> by design. The DOM-parse path is gated
by a cheap regex pre-check so legacy bare <mxGraphModel> callers
don't pay any extra cost. The autoFix duplicate-id rename step is
also guarded against mxfile inputs — renaming those sentinel cells
would silently break drawio's parent references.
* `diagram-operations.ts` accepts an optional PageSelector. For
<mxfile> input it resolves the page first and scopes all
querySelectorAll calls to that page's <root>, so a delete on page 2's
cell "2" no longer touches page 1's cell "2".
* `create_new_diagram` accepts either a bare <mxGraphModel> (legacy,
auto-wrapped into a single-page mxfile) or a full <mxfile> with N
diagrams. All existing single-page callers keep working unchanged.
* `edit_diagram`, `get_diagram`, and `export_diagram` gain optional
`page_id` / `page_name` / `page_index` parameters. When omitted they
target the first page — the "active by convention" default. Tool
handlers with all-optional input schemas coalesce missing arguments
via `input ?? {}` so a no-args MCP invocation can't crash on
destructure before reaching the session-existence check.
* New tools: `list_pages`, `add_page`, `rename_page`, `delete_page`.
* Page-targeted PNG/SVG export uses a "load + export + restore" dance:
the server projects the target page into a single-page <mxfile>,
pushes it into the transient state so the browser reloads the iframe
with just that page, waits for drawio to render (~3s), triggers the
export, captures the data, and then restores the original multi-page
document. The dance is wrapped in `try/finally` so the restore runs
unconditionally — even if an exception is thrown mid-dance, the
user's multi-tab view is recovered before the function returns.
The earlier attempt to use drawio's `selectPage` postMessage was a
no-op because drawio's JSON embed protocol does not expose that
action — silently exporting whatever tab happened to be active. The
load-export-restore approach trades a brief visible tab-flicker for
correctness: the exported image is guaranteed to match the requested
page.
* Tool description strings reflect the multi-page semantics so the LLM
client learns the new contract.
* Package version bumped 0.2.0 → 0.3.0 (additive surface — four new
tools, three extended input schemas, canonical XML shape change).
* CI: `.github/workflows/test.yml` gains an explicit install + vitest
run for the mcp-server package so the new multi-page invariants are
covered by automation, not just local runs.
Backward compatibility: every existing single-page caller continues to
work without modification. The session.xml shape is normalised on every
write, removing the wrapper-injection hack from the .drawio download
path.
Tests: 43 unit tests under `packages/mcp-server/tests/multi-page.test.ts`
pin the validator's mxfile path, the page-scoped operations, the XML
declaration-prefix handling for both normalizeToMxfile and addPageToDoc,
addPageToDoc's rejection of full <mxfile> inputs, the single-page
projection used by export_diagram (a direct regression test for the
selectPage bug — two distinct page selectors must produce visually
different projections), and the Transformer + CNN motivating scenario.
A `tests/smoke.mjs` smoke test drives the built `dist/index.js` over
JSON-RPC and asserts all 9 tools register with the right input schemas.
Root vitest suite (107 tests) still green.
* fix(mcp): rewrite page-targeted export browser-side; harden edit/get
The page-targeted PNG/SVG export never worked: export_diagram swapped the
live session to a single-page projection, slept 3s, then wrote the export
flag onto a state object that setState() had already replaced in the store
Map — so the browser never saw the request and every such export timed out.
The swap+restore also clobbered concurrent edits.
Move the projection entirely browser-side: requestExport() hands a single
-page <mxfile> to the bridge via state.exportXml; the bridge loads it,
lets draw.io render, exports, then reloads the user's real document. The
canonical session state is never mutated, so there is no restore race and
no fixed-delay guessing. The export poll now re-reads the live store entry
each tick instead of a captured reference. autosave is suppressed and the
version-bump reload is skipped while a projection is on screen; if no real
document was captured, restore forces a server reload rather than leaving
the iframe stuck on the projection.
Also:
- edit_diagram now returns isError on a page-level failure (selector matched
no page / page has no <root>) instead of reporting success-with-warnings
and persisting a no-op; the pre-edit history snapshot is taken only after
that gate so a failed edit leaves no phantom undo entry.
- edit_diagram/get_diagram re-normalise browser-pushed xml to mxfile so a
bare <mxGraphModel> can't silently strip a multi-page document.
- get_diagram now errors (instead of silently returning the full doc) when a
selector is given but the session isn't a parseable mxfile.
- page_id / page_name / add_page.id get .min(1) so empty strings can't
silently target the first page.
- Extract pages.ts:projectPage(), collapsing three copies of the
parse→find→serialise projection logic in index.ts.
- Replace the never-in-CI tests/smoke.mjs with tests/server-wiring.test.ts,
which boots the server from source via tsx and runs under the existing
vitest CI step.
* chore(mcp): set version to 0.2.1 for release
---------
Co-authored-by: dayuan.jiang <jdy.toh@gmail.com>
All three POST handlers (/api/state, /api/restore, /api/history-svg)
now use a shared readBody() helper that enforces a 10MB limit and
returns 413 if exceeded, preventing memory exhaustion from oversized
requests.
Bumps @next-ai-drawio/mcp-server to 0.1.19.
The embedded HTTP sidecar was using server.listen(port) without a host
argument, which defaults to 0.0.0.0 (all interfaces). This exposed the
server to the local network. Now explicitly binds to 127.0.0.1.
Also excludes release/ from tsconfig to fix pre-existing TS errors.
Bumps @next-ai-drawio/mcp-server to 0.1.18.
Replace wildcard `Access-Control-Allow-Origin: *` with same-origin check,
preventing external websites from accessing MCP server APIs via cross-origin requests.
* feat: add PNG/SVG export support to MCP server export_diagram tool
Previously export_diagram only supported .drawio XML files. This adds
PNG and SVG export by leveraging the existing browser sync mechanism:
the MCP tool sets an exportFormat flag on the session state, the browser
detects it via polling and triggers an iframe export, then POSTs the
result back as exportData which the tool reads and writes to disk.
* fix: address PR review feedback for export feature
- Validate exportData is a string in POST /api/state
- Update lastUpdated in setExportFormat to prevent session expiry
- Gate export postMessage on isReady to avoid lost messages
- Remove unused fmt variable
- Fix double extension when path has a different supported extension
* fix: resolve high severity npm audit vulnerabilities
Run npm audit fix to update @aws-sdk and @smithy transitive dependencies
that had high severity advisories, which was failing the CI security audit step.
* fix: address second round of PR review feedback
- Add 8s timeout for pendingMcpExport to prevent permanent blocking
- Move export trigger after version update in poll() to export latest diagram
- Return 404 when session not found for exportData POST
- Sync browser state before .drawio export to avoid stale XML
- Handle URL-encoded SVG data URIs in addition to base64
* fix: address third round of PR review feedback
- Sync browser state before PNG/SVG export (not just drawio)
- Add 10MB body size limit on POST /api/state
- Validate export response format matches request to prevent race conditions
* refactor: remove over-engineered defensive code from export feature
Strip unnecessary validation/guards added from Copilot review that
don't make sense for a localhost-only MCP server: body size limit,
type validation, 404 for missing session, lastUpdated refresh,
URL-encoded SVG handling. Also deduplicate requestSync call.
* refactor: keep original drawio export path unchanged
Don't restructure the existing drawio logic - just add png/svg
as a separate branch after it.
* refactor: remove redundant helper functions, inline state access
Remove setExportFormat/getExportData/clearExportData wrappers that
were each called once. Access state fields directly via getState().
* chore: bump mcp-server version to 0.1.16
* feat(mcp): update UI with project logo and modern dialog styles
- Replace Next.js logo with project favicon-white.svg
- Modernize modal dialogs with backdrop blur, animations, and DM Sans font
- Update button styles to match header design
- Change title to "Next AI Draw.io"
- Rename "Save" to "Download" for clarity
- Bump version to 0.1.15
* chore: remove dead code (unused download helpers and pendingManualSave)
Fixes#633 - browser showing infinite loading spinner when accessing
the MCP server URL without the session parameter.
When users access http://localhost:6002 directly (without ?mcp=xxx),
the page now auto-redirects to the most recent active session instead
of showing "No session" with an infinite loading spinner.
After create_new_diagram, edit_diagram would fail with "You must call
get_diagram first" because lastGetDiagramTime was never set (remained 0
from session init). This fix sets lastGetDiagramTime after creating a
diagram, allowing immediate edits.
Fixes#534, Fixes#589
* fix(mcp-server): add graceful shutdown to prevent zombie processes
Add lifecycle handlers to properly exit the MCP server when the parent
application closes:
- Listen for stdin close/end events (primary method for all platforms)
- Handle SIGINT/SIGTERM signals
- Handle stdout broken pipe errors
- Export shutdown() function from http-server to clean up resources
* chore(mcp-server): bump version to 0.1.11
* fix(edit_diagram): implement cascade delete for children and edges
- Add automatic cascade deletion when deleting a cell
- Recursively delete all child cells (parent attribute references)
- Delete all edges referencing deleted cells (source/target)
- Skip silently if cell already deleted (handles AI redundant ops)
- Update prompts to inform AI about cascade behavior
Fixes#450
* fix: add root cell protection and sync MCP server cascade delete
- Add protection for root cells '0' and '1' to prevent full diagram wipe
- Sync MCP server with main app's cascade delete logic
- Both lib/utils.ts and packages/mcp-server now have identical delete behavior
* chore(mcp): bump version to 0.1.9
* fix(cascade-delete): recursively collect edge children (labels)
- Change from cellsToDelete.add(edgeId) to collectDescendants(edgeId)
- Fixes orphaned edge labels causing draw.io to crash/clear canvas
- Edge labels (parent=edgeId) are now deleted with their parent edge
Fixes#374 - Models were confused by the `type` field name and sent
`operation` instead. This change:
- Renames DiagramOperation.type to DiagramOperation.operation across
all files (MCP server, web app, hooks, components, system prompts)
- Adds JSON examples in tool descriptions to show correct format
- Updates all test data to use the new field name
Affected files:
- lib/utils.ts
- app/api/chat/route.ts
- hooks/use-diagram-tool-handlers.ts
- components/chat-message-display.tsx
- lib/system-prompts.ts
- packages/mcp-server/src/diagram-operations.ts
- packages/mcp-server/src/index.ts
- scripts/test-diagram-operations.mjs
MCP server version bumped to 0.1.6
* feat(mcp): add XML validation and auto-fix to MCP server
- Add xml-validation.ts with validateAndFixXml function
- Integrate validation into display_diagram tool (fails if unfixable)
- Integrate validation into edit_diagram tool (auto-fix each operation)
- Fix bug: typo fixes now run before foreign tag removal
- Fix bug: use before/after comparison instead of regex .test()
* style: auto-format with Biome
* chore(mcp): bump version to 0.1.3
---------
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
* feat: add MCP server package for npx distribution
- Self-contained MCP server with embedded HTTP server
- Real-time browser preview via draw.io iframe
- Tools: start_session, display_diagram, edit_diagram, get_diagram, export_diagram
- Port retry limit (6002-6020) and session TTL cleanup (1 hour)
- Published as @next-ai-drawio/mcp-server on npm
* chore: bump version to 0.1.2
* docs: add MCP server section to README (preview feature)
* docs: add multi-client installation instructions for MCP server
* fix: exclude packages from Next.js build
* docs: use @latest instead of -y flag for npx (match Playwright MCP style)
* chore: bump version to 0.4.3 and add release notes
* chore: remove release notes
* feat: add MCP server notice to example panel
