- 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
* refactor: replace text-based edit_diagram with ID-based operations
- Add applyDiagramOperations() function using DOMParser for ID lookup
- New schema: operations array with type (update/add/delete), cell_id, new_xml
- Update chat-panel.tsx handler for new operations format
- Update OperationsDisplay component to show operation type and cell_id
- Simplify system prompts with new ID-based examples
- Add ID validation for add operations
- Add warning for edges referencing deleted cells
* fix: add ID validation to update operation and remove dead code
- Add ID mismatch validation to update operation (consistency with add)
- Remove orphaned replaceXMLParts function (~300 lines of dead code)
- Update cell_id schema description for clarity
- Add unit tests for applyDiagramOperations (11 tests)
The hasValidDiagramXml filter was deleting valid messages that had minor
XML issues. Error handling in handleDisplayChart now catches all errors,
so filtering is no longer needed - invalid XML just won't load the diagram
but the conversation is preserved.
When LLM generates invalid XML, the app previously saved corrupted messages
to localStorage, causing an unrecoverable crash loop on restart.
This fix validates messages when restoring from localStorage and filters out
any with invalid diagram XML. Users see a toast notification when corrupted
messages are removed.
Fixes#240
* feat: add minimal style mode toggle for faster diagram generation
- Add Minimal/Styled toggle switch in chat input UI
- When enabled, removes color/style instructions from system prompt
- Faster generation with plain black/white diagrams
- Improves XML auto-fix: handle foreign tags, extra closing tags, trailing garbage
- Fix isMxCellXmlComplete to strip Anthropic function-calling wrappers
- Add debug logging for truncation detection diagnosis
* fix: prevent false XML parse errors during streaming
- Escape unescaped & characters in convertToLegalXml() before DOMParser validation
- Only log console.error for final output, not during streaming updates
- Prevents Next.js dev mode error overlay from showing for expected streaming states
* refactor: simplify LLM XML format to output bare mxCells only
- Update wrapWithMxFile() to always add root cells (id=0, id=1) automatically
- LLM now generates only mxCell elements starting from id=2 (no wrapper tags)
- Update system prompts and tool descriptions with new format instructions
- Update cached responses to remove root cells and wrapper tags
- Update truncation detection to check for complete mxCell endings
- Update documentation in xml_guide.md
* fix: address PR review issues for XML format refactor
- Fix critical bug: inconsistent truncation check using old </root> pattern
- Fix stale error message referencing </root> tag
- Add isMxCellXmlComplete() helper for consistent truncation detection
- Improve regex patterns to handle any attribute order in root cells
- Update wrapWithMxFile JSDoc to document root cell removal behavior
* fix: handle non-self-closing root cells in wrapWithMxFile regex
* feat: add append_diagram tool for truncation continuation
When LLM output hits maxOutputTokens mid-generation, instead of
failing with an error loop, the system now:
1. Detects truncation (missing </root> in XML)
2. Stores partial XML and tells LLM to use new append_diagram tool
3. LLM continues generating from where it stopped
4. Fragments are accumulated until XML is complete
5. Server limits to 5 steps via stepCountIs(5)
Key changes:
- Add append_diagram tool definition in route.ts
- Add append_diagram handler in chat-panel.tsx
- Track continuation mode separately from error mode
- Continuation mode has unlimited retries (not counted against limit)
- Error mode still limited to MAX_AUTO_RETRY_COUNT (1)
- Update system prompts to document append_diagram tool
* fix: show friendly message and yellow badge for truncated output
- Add yellow 'Truncated' badge in UI instead of red 'Error' when XML is incomplete
- Show friendly error message for toolUse.input is invalid errors
- Built on top of append_diagram continuation feature
* refactor: remove debug logs and simplify truncation state
- Remove all debug console.log statements
- Remove isContinuationModeRef, derive from partialXmlRef.current.length > 0
* docs: fix append_diagram instructions for consistency
- Change 'Do NOT include' to 'Do NOT start with' (clearer intent)
- Add <mxCell id="0"> to prohibited start patterns
- Change 'closing tags </root></mxGraphModel>' to just '</root>' (wrapWithMxFile handles the rest)
* fix: handle malformed XML from DeepSeek gracefully
Add early XML validation with parsererror check before calling
replaceNodes to prevent application crashes when AI models
generate malformed XML with unescaped special characters.
Changes:
- Add toast import from sonner
- Parse and validate XML before processing
- Add parsererror detection to catch malformed XML early
- Wrap replaceNodes in try-catch for additional safety
- Add user-friendly toast notifications for all error cases
- Change console.log to console.error for validation failures
Fixes#220#230#231
* fix: prevent toast spam during streaming and merge silent failure fixes
- Only show error toasts after streaming completes (not during partial updates)
- Track which tool calls have shown errors to prevent duplicate toasts
- Merge clipboard copy error handling from PR #236
- Merge feedback submission error handling from PR #237
- Add comments explaining streaming vs completion behavior
* refactor: simplify toast deduplication with boolean flag
Based on code review feedback, simplified the approach from tracking
per-tool-call IDs in a Set to using a single boolean flag.
Changes:
- Replaced Set<string> with boolean ref for toast tracking
- Removed toolCallId and showToast parameters from handleDisplayChart
- Reset flag when streaming starts (simpler mental model)
- Same behavior: one toast per streaming session, no spam
Benefits:
- Fewer concepts (1 boolean vs Set + 2 parameters)
- No manual coordination between call sites
- Easier to understand and maintain
- ~15 fewer lines of tracking logic
* fix: only show toast for final malformed XML, not during streaming
- Remove errorToastShownRef tracking (no longer needed)
- Add showToast parameter to handleDisplayChart (default false)
- Pass false during streaming (XML may be incomplete)
- Pass true at completion (show toast if final XML is malformed)
- Simpler and more explicit error handling
When feedback submission to the API fails, revert the optimistic
UI update and show a toast notification to inform the user.
Changes:
- Add toast import from sonner
- Change console.warn to console.error for proper logging
- Add toast.error() notification when API call fails
- Revert optimistic UI update by removing feedback from state
Previously, feedback submission failures were completely silent.
Users would see the thumbs-up/down visual feedback but their
feedback was never recorded. This creates a false sense that
the feedback was successfully submitted.
Now users are immediately notified when submission fails and
can retry their feedback.
Add toast notification when clipboard copy operation fails,
so users know when their copy attempt was unsuccessful.
Changes:
- Add toast import from sonner
- Add toast.error() notification when clipboard copy fails
- Show clear message: "Failed to copy message. Please copy
manually or check clipboard permissions."
Previously, clipboard copy failures were only indicated by a
brief visual state change (setCopyFailedMessageId), which users
might miss. Now users receive persistent feedback when copy
operations fail.
* feat: Add a new chat button with a confirmation modal
* Fix for PR comments
* fix: add error handling and proper cleanup in handleNewChat
- Add try-catch for localStorage operations to handle quota exceeded,
private browsing, and other storage errors
- Use handleFileChange([]) instead of setFiles([]) to properly clear
pdfData Map alongside files
- Only show success toast when localStorage operations succeed
- Show warning toast if localStorage fails but chat state is cleared
---------
Co-authored-by: Dayuan Jiang <jdy.toh@gmail.com>
* fix: improve Azure provider auto-detection and validation (#223)
- Fix detectProvider() to only detect Azure when it has complete config
(both AZURE_API_KEY and AZURE_RESOURCE_NAME or AZURE_BASE_URL)
- Add validation in validateProviderCredentials() for Azure to provide
clear error messages when configuration is incomplete
- Update docs/ai-providers.md to clarify Azure requires resource name
* docs: add Azure reasoning options to documentation
- Add MAX_AUTO_RETRY_COUNT (3) to prevent infinite retry loops
- Check token and TPM limits before each auto-retry
- Reset retry counter on user-initiated messages
- Show toast notification when limits are reached
Fixes issue where models returning invalid tool inputs caused 45+ API
requests due to sendAutomaticallyWhen having no retry limit or quota check.
Some models (e.g. minimax) copy placeholder text instead of generating
fresh XML, causing tool call validation failures and infinite loops.
Added ENABLE_HISTORY_XML_REPLACE env var (default: false) to control
this behavior.
Added full content of the Chain-of-Thought Prompting paper by Wei et al. from Google Research. This example file demonstrates how chain-of-thought reasoning improves LLM performance on complex reasoning tasks.
Add NEXT_PUBLIC_MAX_EXTRACTED_CHARS environment variable to allow
configuring the maximum characters extracted from PDF and text files.
Defaults to 150000 (150k chars) if not set.
Previously AZURE_RESOURCE_NAME was documented in env.example but not
actually used in the code. This caused Azure OpenAI configuration to fail
when users set AZURE_RESOURCE_NAME instead of AZURE_BASE_URL.
Changes:
- Read AZURE_RESOURCE_NAME from environment and pass to createAzure()
- resourceName constructs endpoint: https://{name}.openai.azure.com/openai/v1
- baseURL takes precedence over resourceName when both are set
- Updated env.example with clearer documentation
Fixes#208
- Changed sendAutomaticallyWhen to only auto-resubmit on tool errors
- Extracted logic to shouldAutoResubmit() function with JSDoc
- Added TypeScript interfaces for type safety (MessagePart, ChatMessage)
- Wrapped debug logs with DEBUG flag for production readiness
- Added TOOL_ERROR_STATE constant to avoid hardcoded strings
Problem: AI was regenerating diagrams 3+ times even after successful display
Root cause: lastAssistantMessageIsCompleteWithToolCalls auto-resubmits on both success AND error
Solution: Custom logic that only auto-resubmits on errors, stops on success
- Add client-side PDF text extraction using unpdf library
- Support text files (.txt, .md, .json, .csv, .py, .js, .ts, etc.)
- Add file preview with character count for PDF/text files
- Add 150k character limit for extracted content
- Highlight Paper to Diagram example with NEW badge
- Fix React hydration error by adding explicit IDs to ResizablePanelGroup
- Remove code duplication by centralizing file utilities in pdf-utils.ts
- Add replaceHistoricalToolInputs to replace XML in tool calls with placeholders
- Send both previousXml and current xml so LLM can understand user's manual edits
- Update system message to mark current XML as authoritative source of truth
- Fix React StrictMode issue with blob URL cleanup in FilePreviewList
- Add unoptimized prop to Image components for blob URLs
Summary
- Adds browser theme detection on first visit using
prefers-color-scheme media query
- Renames localStorage key from dark-mode to
next-ai-draw-io-dark-mode for consistency with other keys
- Uses STORAGE_DIAGRAM_XML_KEY constant instead of hardcoded
string in diagram-context.tsx
Changes
app/page.tsx:
- On first visit (no saved preference), detect browser's color
scheme preference
- Update localStorage key to follow project naming convention
(next-ai-draw-io-*)
contexts/diagram-context.tsx:
- Import STORAGE_DIAGRAM_XML_KEY from chat-panel.tsx
- Replace hardcoded "next-ai-draw-io-diagram-xml" with the
constant
