- edit_diagram runs the MCP server's editDiagram: every new_xml is checked
first, one cell per operation, and after the edit only the target page
is checked, rejecting only errors this edit introduced. An unrelated
problem elsewhere in the document no longer blocks every edit. The
error lists each failed operation
- The streaming edit preview uses the MCP applyDiagramOperations
- Delete applyDiagramOperations (292 lines) and wrapWithMxFile from
lib/utils.ts, and the unused hand-copied scripts/test-diagram-operations.mjs
- One blank document (BLANK_MXFILE) for the web app and the MCP preview,
replacing four copies
- Saving a .drawio wraps a bare model with normalizeToMxfile
- The empty-diagram check uses hasCells, which also counts cells wrapped
in a UserObject/object
- DiagramOperation is the MCP type
- The wrapped-cell and empty-diagram tests now run against the MCP code
- New e2e test: edit_diagram changes the canvas, and a failing edit
leaves it as it was
- Delete the web app's own copy of the XML checks and repairs from
lib/utils.ts (1,074 lines). loadDiagram now uses the MCP server's
validateAndFixXml without the strict checks, because the XML may hold
the user's own diagram
- display_diagram and append_diagram prepare the model's XML with the new
shared prepareNewDiagram, also used by the MCP create_new_diagram: wrap,
validate strictly and auto-fix while it is still a bare model (where
duplicate ids are renamed), then turn it into an mxfile
- The streaming preview of display_diagram no longer redraws the model's
raw cells after the tool handler loaded the checked diagram, and drops
a queued preview once the input is complete. That redraw lost
auto-fixes and UserObject/object wrappers, so a linked cell lost its
label; it also showed a second error toast
- The web repair regression tests now run against the MCP functions
- New e2e test checks the canvas content after display_diagram
- Fix the e2e upload tests, whose file input locator also matched the
template import input
- Autosave guard reads refs, so edits after a theme or dark mode switch are kept
- Duplicate-id check and rename run per page; repair loop no longer quadratic
- autoFixXml no longer breaks style values, rich text " or single-line cells
- extractCompleteMxCells keeps the cell after a self-closing cell
- Better truncation detection; object/UserObject wrapped cells are editable
- Exports for thumbnail, PNG and save are routed by tag instead of a shared resolver
- History stores the full document; storage errors are reported, no auto-deletion of chats
- IndexedDB connection reopens after errors; focus refresh throttled
- Keep ?session= on locale redirect, map zh-Hant to zh-tw for draw.io
* feat(session): add chat session history with IndexedDB storage
- Add session-storage.ts with IndexedDB wrapper using idb library
- Add use-session-manager.ts hook for session state management
- Add session-history-dropdown.tsx for session selection UI
- Integrate session system into chat-panel.tsx
- Auto-generate session titles from first user message
- Auto-save sessions on message completion
- Support session switching, deletion, and creation
- Migrate existing localStorage data to IndexedDB
- Add i18n translations for session history UI
* feat(session): improve history dropdown and persist diagram history
- Add time-based grouping (Today, Yesterday, This Week, Earlier)
- Add thumbnail previews using Next.js Image component
- Add staggered entrance animations with fade-in effects
- Improve active session indicator with left border accent
- Fix scrolling by using native overflow instead of ScrollArea
- Persist diagram version history to IndexedDB sessions
- Remove redundant diagram XML from localStorage
- Add i18n strings for time group labels (en, ja, zh)
* fix(session): prevent data loss on theme change and tab close
- Add isDrawioReady effect to restore diagram after DrawIO remount
- Add visibilitychange handler to save session when page becomes hidden
- Fix missing currentSessionId in saveCurrentSession dependency array
- Remove unused sanitizeMessages import from use-session-manager
* fix(session): fix diagram save and migration data loss bugs
- Add diagramHistory to save effect dependency array so diagram-only
edits trigger saves (previously only message changes did)
- Destructure stable sessionManager values to prevent unnecessary
effect re-runs on every render
- Add try-catch wrapper around debounced async save operation
- Make saveSession() return boolean to indicate success/failure
- Verify IndexedDB write succeeded before deleting localStorage data
during migration (prevents data loss if write silently fails)
- Keep localStorage data for retry if migration fails instead of
marking as complete anyway
* refactor(session): extract helpers to reduce code duplication
- Add syncUIWithSession helper to consolidate 4 duplicate UI sync blocks
- Add buildSessionData helper to consolidate 4 duplicate save logic blocks
- Remove unused saveTimeoutRef and its cleanup effect
- Net reduction of ~80 lines of duplicate code
* style(ui): improve history dropdown and delete dialog styling
- Change destructive color from coral to muted rose for refined look
- Make session history panel taller (400px fixed height)
- Fix popover alignment to prevent truncation
- Style delete button with soft red outline instead of solid fill
- Make delete dialog more compact (max-w-sm)
* fix(session): reset refs on new chat and show recent sessions
- Fix cached example diagrams not displaying after creating new session
- Reset previousXML, lastProcessedXmlRef and processedToolCalls when
messages become empty (new chat or session switch)
- Add recent chats section in empty chat state with collapsible examples
- Pass sessions and onSelectSession to ChatMessageDisplay
- Add loadedMessageIdsRef to skip animations on session restore
- Add debug console.log for diagram processing flow
* feat(session): add search bar and improve history UI
- Remove session history dropdown, use main panel instead
- Add search bar to filter history chats by title
- Show minutes (Xm ago) instead of "Just now" for recent sessions
- Scroll to top when switching to new/empty chat
- Remove title truncation limit for better searchability
- Remove debug console.log statements
* refactor: remove redundant code and fix nested button hydration error
- Remove unused 'sessions' from deleteSession dependency array
- Remove unused 'switchedTo' variable and simplify return type
- Remove unused 'restoredMessageIdsRef' (always empty)
- Fix nested button hydration error by using div with role=button
- Simplify handleDeleteSession callback
* fix(session): fix migration bug, improve metadata perf, truncate titles
- Fix migration retry loop when localStorage has empty array
- Use cursor-based iteration for getAllSessionMetadata
- Truncate session titles to 100 chars with ellipsis
* refactor: remove dead code and extract diagram length constant
- Remove unused exports: getAllSessions, createNewSession, updateSessionTitle
- Remove write-only CURRENT_SESSION_KEY and all localStorage calls
- Remove dead messagesEndRef and unused scroll effect
- Extract magic number 300 to MIN_REAL_DIAGRAM_LENGTH constant
- Add isRealDiagram() helper function for semantic clarity
* 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
- Add HTML escaping (<, >) in convertToLegalXml for attribute values
- Update isMxCellXmlComplete to handle any LLM provider's wrapper tags
- Add wrapper tag stripping in wrapWithMxFile for DeepSeek/Anthropic tags
- Update autoFixXml to escape both < and > in attribute values
Fixes 'Malformed XML detected in final output' error when AI generates
diagrams with HTML content in value attributes like <b>Title</b>.
- Add extractCompleteMxCells() to extract only complete mxCell elements from partial XML
- Remove useEffect cleanup that was killing debounce timeouts on every re-render
- Wrap XML in <root> tags for proper DOMParser validation
Previously, diagrams only rendered after ALL XML finished streaming because:
1. useEffect cleanup cleared the 150ms debounce timeout on every message change
2. DOMParser rejected partial XML like '<mxCell id="2" value="...' (incomplete)
Now each complete mxCell renders progressively as it finishes streaming.
* 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>
* 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)
* 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: support minimax model with XML wrapping fix
- Add wrapWithMxFile utility to properly wrap XML for draw.io
- Fix 'Not a diagram file' error when model generates raw <root> XML
- Add supportsPromptCaching check for conditional caching
- Only enable Bedrock prompt caching for Claude models
* docs: update model mention to minimax-m2 across About pages and READMEs
- Update tooltip in chat-panel.tsx to mention minimax-m2 model change
- Update English, Chinese, and Japanese About pages with model change info
- Update English, Chinese, and Japanese READMEs with demo site model note
---------
Co-authored-by: dayuan.jiang <[email protected]>
- Save and restore chat messages, XML snapshots, session ID, and diagram XML to localStorage
- Restore diagram when DrawIO becomes ready (using new onLoad callback)
- Change close protection default to false since auto-save handles persistence
- Clear localStorage when clearing chat
- Handle edge cases: undefined edit fields, empty chartXML, missing access code header
- Add validation for orphaned mxPoint elements in validateMxCellStructure()
- Add cleanup of orphaned mxPoint elements in convertToLegalXml()
- Orphaned mxPoints cause 'Could not add object mxPoint' errors in draw.io
- mxPoint elements must have 'as' attribute or be inside <Array as="points">
Co-authored-by: dayuan.jiang <[email protected]>
- Add 6th strategy: match by value attribute (label text)
- Add 7th strategy: normalized whitespace match
- Remove lastProcessedIndex tracking - always search from beginning
- Pairs may not be in document order, so sequential tracking was unreliable
Co-authored-by: dayuan.jiang <[email protected]>
- Add Biome as formatter and linter (replaces Prettier)
- Configure Husky + lint-staged for pre-commit hooks
- Add VS Code settings for format on save
- Ignore components/ui/ (shadcn generated code)
- Remove semicolons, use 4-space indent
- Reformat all files to new style
- Update log-feedback API to find existing chat trace by sessionId and attach score to it
- Update log-save API to create span on existing chat trace instead of standalone trace
- Add thumbs up/down feedback buttons on assistant messages
- Add message regeneration and edit functionality
- Add save dialog with format selection (drawio, png, svg)
- Pass sessionId through components for Langfuse linking
- Extract system prompts to dedicated lib/system-prompts.ts module
- Add extended system prompt (~4000 tokens) for models with higher cache minimums (Opus 4.5, Haiku 4.5)
- Clean up debug logs while preserving informational and cache-related logs
- Improve code formatting and organization in chat route
- Add essential draw.io XML structure rules to system prompt
- Include critical rules about mxCell nesting (all must be direct children of root)
- Add shape/vertex and connector/edge examples with proper structure
- Improve tool description for display_diagram with validation rules
- Update xml_guide.md with better swimlane examples showing flat structure
- Add client-side XML validation to catch nested mxCell errors early
Helps address issues #40 (local Ollama models not working) and #39 (mxCell nesting errors)
- Add formatXML function to format single-line XML with proper indentation
- Format chartXml after fetching to ensure consistency
- Update replaceXMLParts to handle single-line XML with substring fallback
- Improve edit_diagram tool guidance with SEARCH/REPLACE best practices
- Add concrete examples to help AI use minimal, targeted edits
dayuan.jiang