fix: edit_diagram streaming and JSON repair improvements (#271)

- Add shared editDiagramOriginalXmlRef between streaming preview and tool handler
  to avoid conflicts when applying operations (fixes "cell already exists" errors)
- Add JSON repair preprocessing to fix LLM-generated malformed JSON like `:=`
- Filter out tool calls with invalid/undefined inputs from interrupted streaming
- Remove perf console logs

app/api/chat/route.ts

@@ -70,29 +70,41 @@ function isMinimalDiagram(xml: string): boolean {
 
 // Helper function to replace historical tool call XML with placeholders
 // This reduces token usage and forces LLM to rely on the current diagram XML (source of truth)
+// Also fixes invalid/undefined inputs from interrupted streaming
 function replaceHistoricalToolInputs(messages: any[]): any[] {
     return messages.map((msg) => {
         if (msg.role !== "assistant" || !Array.isArray(msg.content)) {
             return msg
         }
-        const replacedContent = msg.content.map((part: any) => {
+        const replacedContent = msg.content
-            if (part.type === "tool-call") {
+            .map((part: any) => {
-                const toolName = part.toolName
+                if (part.type === "tool-call") {
-                if (
+                    const toolName = part.toolName
-                    toolName === "display_diagram" ||
+                    // Fix invalid/undefined inputs from interrupted streaming
-                    toolName === "edit_diagram"
+                    if (
-                ) {
+                        !part.input ||
-                    return {
+                        typeof part.input !== "object" ||
-                        ...part,
+                        Object.keys(part.input).length === 0
-                        input: {
+                    ) {
-                            placeholder:
+                        // Skip tool calls with invalid inputs entirely
-                                "[XML content replaced - see current diagram XML in system context]",
+                        return null
-                        },
+                    }
+                    if (
+                        toolName === "display_diagram" ||
+                        toolName === "edit_diagram"
+                    ) {
+                        return {
+                            ...part,
+                            input: {
+                                placeholder:
+                                    "[XML content replaced - see current diagram XML in system context]",
+                            },
+                        }
                     }
                 }
-            }
+                return part
-            return part
+            })
-        })
+            .filter(Boolean) // Remove null entries (invalid tool calls)
         return { ...msg, content: replacedContent }
     })
 }
@@ -231,6 +243,36 @@ ${userInputText}
     // Convert UIMessages to ModelMessages and add system message
     const modelMessages = convertToModelMessages(messages)
 
+    // DEBUG: Log incoming messages structure
+    console.log("[route.ts] Incoming messages count:", messages.length)
+    messages.forEach((msg: any, idx: number) => {
+        console.log(
+            `[route.ts] Message ${idx} role:`,
+            msg.role,
+            "parts count:",
+            msg.parts?.length,
+        )
+        if (msg.parts) {
+            msg.parts.forEach((part: any, partIdx: number) => {
+                if (
+                    part.type === "tool-invocation" ||
+                    part.type === "tool-result"
+                ) {
+                    console.log(`[route.ts]   Part ${partIdx}:`, {
+                        type: part.type,
+                        toolName: part.toolName,
+                        hasInput: !!part.input,
+                        inputType: typeof part.input,
+                        inputKeys:
+                            part.input && typeof part.input === "object"
+                                ? Object.keys(part.input)
+                                : null,
+                    })
+                }
+            })
+        }
+    })
+
     // Replace historical tool call XML with placeholders to reduce tokens
     // Disabled by default - some models (e.g. minimax) copy placeholders instead of generating XML
     const enableHistoryReplace =
@@ -246,6 +288,63 @@ ${userInputText}
             msg.content && Array.isArray(msg.content) && msg.content.length > 0,
     )
 
+    // Filter out tool-calls with invalid inputs (from failed repair or interrupted streaming)
+    // Bedrock API rejects messages where toolUse.input is not a valid JSON object
+    enhancedMessages = enhancedMessages
+        .map((msg: any) => {
+            if (msg.role !== "assistant" || !Array.isArray(msg.content)) {
+                return msg
+            }
+            const filteredContent = msg.content.filter((part: any) => {
+                if (part.type === "tool-call") {
+                    // Check if input is a valid object (not null, undefined, or empty)
+                    if (
+                        !part.input ||
+                        typeof part.input !== "object" ||
+                        Object.keys(part.input).length === 0
+                    ) {
+                        console.warn(
+                            `[route.ts] Filtering out tool-call with invalid input:`,
+                            { toolName: part.toolName, input: part.input },
+                        )
+                        return false
+                    }
+                }
+                return true
+            })
+            return { ...msg, content: filteredContent }
+        })
+        .filter((msg: any) => msg.content && msg.content.length > 0)
+
+    // DEBUG: Log modelMessages structure (what's being sent to AI)
+    console.log("[route.ts] Model messages count:", enhancedMessages.length)
+    enhancedMessages.forEach((msg: any, idx: number) => {
+        console.log(
+            `[route.ts] ModelMsg ${idx} role:`,
+            msg.role,
+            "content count:",
+            msg.content?.length,
+        )
+        if (msg.content) {
+            msg.content.forEach((part: any, partIdx: number) => {
+                if (part.type === "tool-call" || part.type === "tool-result") {
+                    console.log(`[route.ts]   Content ${partIdx}:`, {
+                        type: part.type,
+                        toolName: part.toolName,
+                        hasInput: !!part.input,
+                        inputType: typeof part.input,
+                        inputValue:
+                            part.input === undefined
+                                ? "undefined"
+                                : part.input === null
+                                  ? "null"
+                                  : "object",
+                    })
+                }
+            })
+        }
+    })
+
     // Update the last message with user input only (XML moved to separate cached system message)
     if (enhancedMessages.length >= 1) {
         const lastModelMessage = enhancedMessages[enhancedMessages.length - 1]
@@ -327,14 +426,30 @@ ${userInputText}
         stopWhen: stepCountIs(5),
         // Repair truncated tool calls when maxOutputTokens is reached mid-JSON
         experimental_repairToolCall: async ({ toolCall, error }) => {
+            // DEBUG: Log what we're trying to repair
+            console.log(`[repairToolCall] Tool: ${toolCall.toolName}`)
+            console.log(
+                `[repairToolCall] Error: ${error.name} - ${error.message}`,
+            )
+            console.log(`[repairToolCall] Input type: ${typeof toolCall.input}`)
+            console.log(`[repairToolCall] Input value:`, toolCall.input)
+
             // Only attempt repair for invalid tool input (broken JSON from truncation)
             if (
                 error instanceof InvalidToolInputError ||
                 error.name === "AI_InvalidToolInputError"
             ) {
                 try {
+                    // Pre-process to fix common LLM JSON errors that jsonrepair can't handle
+                    let inputToRepair = toolCall.input
+                    if (typeof inputToRepair === "string") {
+                        // Fix `:=` instead of `: ` (LLM sometimes generates this)
+                        inputToRepair = inputToRepair.replace(/:=/g, ": ")
+                        // Fix `= "` instead of `: "`
+                        inputToRepair = inputToRepair.replace(/=\s*"/g, ': "')
+                    }
                     // Use jsonrepair to fix truncated JSON
-                    const repairedInput = jsonrepair(toolCall.input)
+                    const repairedInput = jsonrepair(inputToRepair)
                     console.log(
                         `[repairToolCall] Repaired truncated JSON for tool: ${toolCall.toolName}`,
                     )
@@ -344,6 +459,26 @@ ${userInputText}
                         `[repairToolCall] Failed to repair JSON for tool: ${toolCall.toolName}`,
                         repairError,
                     )
+                    // Return a placeholder input to avoid API errors in multi-step
+                    // The tool will fail gracefully on client side
+                    if (toolCall.toolName === "edit_diagram") {
+                        return {
+                            ...toolCall,
+                            input: {
+                                operations: [],
+                                _error: "JSON repair failed - no operations to apply",
+                            },
+                        }
+                    }
+                    if (toolCall.toolName === "display_diagram") {
+                        return {
+                            ...toolCall,
+                            input: {
+                                xml: "",
+                                _error: "JSON repair failed - empty diagram",
+                            },
+                        }
+                    }
                     return null
                 }
             }

components/chat-message-display.tsx

@@ -28,6 +28,7 @@ import {
 } from "@/components/ai-elements/reasoning"
 import { ScrollArea } from "@/components/ui/scroll-area"
 import {
+    applyDiagramOperations,
     convertToLegalXml,
     isMxCellXmlComplete,
     replaceNodes,
@@ -42,6 +43,23 @@ interface DiagramOperation {
     new_xml?: string
 }
 
+// Helper to extract complete operations from streaming input
+function getCompleteOperations(
+    operations: DiagramOperation[] | undefined,
+): DiagramOperation[] {
+    if (!operations || !Array.isArray(operations)) return []
+    return operations.filter(
+        (op) =>
+            op &&
+            typeof op.type === "string" &&
+            ["update", "add", "delete"].includes(op.type) &&
+            typeof op.cell_id === "string" &&
+            op.cell_id.length > 0 &&
+            // delete doesn't need new_xml, update/add do
+            (op.type === "delete" || typeof op.new_xml === "string"),
+    )
+}
+
 // Tool part interface for type safety
 interface ToolPartLike {
     type: string
@@ -167,6 +185,7 @@ interface ChatMessageDisplayProps {
     setInput: (input: string) => void
     setFiles: (files: File[]) => void
     processedToolCallsRef: MutableRefObject<Set<string>>
+    editDiagramOriginalXmlRef: MutableRefObject<Map<string, string>>
     sessionId?: string
     onRegenerate?: (messageIndex: number) => void
     onEditMessage?: (messageIndex: number, newText: string) => void
@@ -178,6 +197,7 @@ export function ChatMessageDisplay({
     setInput,
     setFiles,
     processedToolCallsRef,
+    editDiagramOriginalXmlRef,
     sessionId,
     onRegenerate,
     onEditMessage,
@@ -195,6 +215,14 @@ export function ChatMessageDisplay({
         null,
     )
     const STREAMING_DEBOUNCE_MS = 150 // Only update diagram every 150ms during streaming
+    // Refs for edit_diagram streaming
+    const pendingEditRef = useRef<{
+        operations: DiagramOperation[]
+        toolCallId: string
+    } | null>(null)
+    const editDebounceTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(
+        null,
+    )
     const [expandedTools, setExpandedTools] = useState<Record<string, boolean>>(
         {},
     )
@@ -286,15 +314,12 @@ export function ChatMessageDisplay({
 
     const handleDisplayChart = useCallback(
         (xml: string, showToast = false) => {
-            console.time("perf:handleDisplayChart")
             const currentXml = xml || ""
             const convertedXml = convertToLegalXml(currentXml)
             if (convertedXml !== previousXML.current) {
                 // Parse and validate XML BEFORE calling replaceNodes
-                console.time("perf:DOMParser")
                 const parser = new DOMParser()
                 const testDoc = parser.parseFromString(convertedXml, "text/xml")
-                console.timeEnd("perf:DOMParser")
                 const parseError = testDoc.querySelector("parsererror")
 
                 if (parseError) {
@@ -310,7 +335,6 @@ export function ChatMessageDisplay({
                             "AI generated invalid diagram XML. Please try regenerating.",
                         )
                     }
-                    console.timeEnd("perf:handleDisplayChart")
                     return // Skip this update
                 }
 
@@ -320,14 +344,10 @@ export function ChatMessageDisplay({
                     const baseXML =
                         chartXML ||
                         `<mxfile><diagram name="Page-1" id="page-1"><mxGraphModel><root><mxCell id="0"/><mxCell id="1" parent="0"/></root></mxGraphModel></diagram></mxfile>`
-                    console.time("perf:replaceNodes")
                     const replacedXML = replaceNodes(baseXML, convertedXml)
-                    console.timeEnd("perf:replaceNodes")
 
                     // Validate and auto-fix the XML
-                    console.time("perf:validateAndFixXml")
                     const validation = validateAndFixXml(replacedXML)
-                    console.timeEnd("perf:validateAndFixXml")
                     if (validation.valid) {
                         previousXML.current = convertedXml
                         // Use fixed XML if available, otherwise use original
@@ -364,9 +384,6 @@ export function ChatMessageDisplay({
                         )
                     }
                 }
-                console.timeEnd("perf:handleDisplayChart")
-            } else {
-                console.timeEnd("perf:handleDisplayChart")
             }
         },
         [chartXML, onDisplayChart],
@@ -385,11 +402,6 @@ export function ChatMessageDisplay({
     }, [editingMessageId])
 
     useEffect(() => {
-        console.time("perf:message-display-useEffect")
-        let processedCount = 0
-        let skippedCount = 0
-        let debouncedCount = 0
-
         // Only process the last message for streaming performance
         // Previous messages are already processed and won't change
         const messagesToProcess =
@@ -419,7 +431,6 @@ export function ChatMessageDisplay({
                             const lastXml =
                                 lastProcessedXmlRef.current.get(toolCallId)
                             if (lastXml === xml) {
-                                skippedCount++
                                 return // Skip redundant processing
                             }
 
@@ -439,9 +450,6 @@ export function ChatMessageDisplay({
                                             debounceTimeoutRef.current = null
                                             pendingXmlRef.current = null
                                             if (pendingXml) {
-                                                console.log(
-                                                    "perf:debounced-handleDisplayChart executing",
-                                                )
                                                 handleDisplayChart(
                                                     pendingXml,
                                                     false,
@@ -455,7 +463,6 @@ export function ChatMessageDisplay({
                                         STREAMING_DEBOUNCE_MS,
                                     )
                                 }
-                                debouncedCount++
                             } else if (
                                 state === "output-available" &&
                                 !processedToolCalls.current.has(toolCallId)
@@ -471,17 +478,129 @@ export function ChatMessageDisplay({
                                 processedToolCalls.current.add(toolCallId)
                                 // Clean up the ref entry - tool is complete, no longer needed
                                 lastProcessedXmlRef.current.delete(toolCallId)
-                                processedCount++
+                            }
+                        }
+
+                        // Handle edit_diagram streaming - apply operations incrementally for preview
+                        // Uses shared editDiagramOriginalXmlRef to coordinate with tool handler
+                        if (
+                            part.type === "tool-edit_diagram" &&
+                            input?.operations
+                        ) {
+                            const completeOps = getCompleteOperations(
+                                input.operations as DiagramOperation[],
+                            )
+
+                            if (completeOps.length === 0) return
+
+                            // Capture original XML when streaming starts (store in shared ref)
+                            if (
+                                !editDiagramOriginalXmlRef.current.has(
+                                    toolCallId,
+                                )
+                            ) {
+                                if (!chartXML) {
+                                    console.warn(
+                                        "[edit_diagram streaming] No chart XML available",
+                                    )
+                                    return
+                                }
+                                editDiagramOriginalXmlRef.current.set(
+                                    toolCallId,
+                                    chartXML,
+                                )
+                            }
+
+                            const originalXml =
+                                editDiagramOriginalXmlRef.current.get(
+                                    toolCallId,
+                                )
+                            if (!originalXml) return
+
+                            // Skip if no change from last processed state
+                            const lastCount = lastProcessedXmlRef.current.get(
+                                toolCallId + "-opCount",
+                            )
+                            if (lastCount === String(completeOps.length)) return
+
+                            if (
+                                state === "input-streaming" ||
+                                state === "input-available"
+                            ) {
+                                // Queue the operations for debounced processing
+                                pendingEditRef.current = {
+                                    operations: completeOps,
+                                    toolCallId,
+                                }
+
+                                if (!editDebounceTimeoutRef.current) {
+                                    editDebounceTimeoutRef.current = setTimeout(
+                                        () => {
+                                            const pending =
+                                                pendingEditRef.current
+                                            editDebounceTimeoutRef.current =
+                                                null
+                                            pendingEditRef.current = null
+
+                                            if (pending) {
+                                                const origXml =
+                                                    editDiagramOriginalXmlRef.current.get(
+                                                        pending.toolCallId,
+                                                    )
+                                                if (!origXml) return
+
+                                                try {
+                                                    const {
+                                                        result: editedXml,
+                                                    } = applyDiagramOperations(
+                                                        origXml,
+                                                        pending.operations,
+                                                    )
+                                                    handleDisplayChart(
+                                                        editedXml,
+                                                        false,
+                                                    )
+                                                    lastProcessedXmlRef.current.set(
+                                                        pending.toolCallId +
+                                                            "-opCount",
+                                                        String(
+                                                            pending.operations
+                                                                .length,
+                                                        ),
+                                                    )
+                                                } catch (e) {
+                                                    console.warn(
+                                                        `[edit_diagram streaming] Operation failed:`,
+                                                        e instanceof Error
+                                                            ? e.message
+                                                            : e,
+                                                    )
+                                                }
+                                            }
+                                        },
+                                        STREAMING_DEBOUNCE_MS,
+                                    )
+                                }
+                            } else if (
+                                state === "output-available" &&
+                                !processedToolCalls.current.has(toolCallId)
+                            ) {
+                                // Final state - cleanup streaming refs (tool handler does final application)
+                                if (editDebounceTimeoutRef.current) {
+                                    clearTimeout(editDebounceTimeoutRef.current)
+                                    editDebounceTimeoutRef.current = null
+                                }
+                                lastProcessedXmlRef.current.delete(
+                                    toolCallId + "-opCount",
+                                )
+                                processedToolCalls.current.add(toolCallId)
+                                // Note: Don't delete editDiagramOriginalXmlRef here - tool handler needs it
                             }
                         }
                     }
                 })
             }
         })
-        console.log(
-            `perf:message-display-useEffect processed=${processedCount} skipped=${skippedCount} debounced=${debouncedCount}`,
-        )
-        console.timeEnd("perf:message-display-useEffect")
 
         // Cleanup: clear any pending debounce timeout on unmount
         return () => {
@@ -489,8 +608,12 @@ export function ChatMessageDisplay({
                 clearTimeout(debounceTimeoutRef.current)
                 debounceTimeoutRef.current = null
             }
+            if (editDebounceTimeoutRef.current) {
+                clearTimeout(editDebounceTimeoutRef.current)
+                editDebounceTimeoutRef.current = null
+            }
         }
-    }, [messages, handleDisplayChart])
+    }, [messages, handleDisplayChart, chartXML])
 
     const renderToolPart = (part: ToolPartLike) => {
         const callId = part.toolCallId

components/chat-panel.tsx

@@ -202,6 +202,10 @@ export default function ChatPanel({
     // Persist processed tool call IDs so collapsing the chat doesn't replay old tool outputs
     const processedToolCallsRef = useRef<Set<string>>(new Set())
 
+    // Store original XML for edit_diagram streaming - shared between streaming preview and tool handler
+    // Key: toolCallId, Value: original XML before any operations applied
+    const editDiagramOriginalXmlRef = useRef<Map<string, string>>(new Map())
+
     // Debounce timeout for localStorage writes (prevents blocking during streaming)
     const localStorageDebounceRef = useRef<ReturnType<
         typeof setTimeout
@@ -333,13 +337,22 @@ ${finalXml}
 
                 let currentXml = ""
                 try {
-                    // Use chartXML from ref directly - more reliable than export
+                    // Use the original XML captured during streaming (shared with chat-message-display)
-                    const cachedXML = chartXMLRef.current
+                    // This ensures we apply operations to the same base XML that streaming used
-                    if (cachedXML) {
+                    const originalXml = editDiagramOriginalXmlRef.current.get(
-                        currentXml = cachedXML
+                        toolCall.toolCallId,
+                    )
+                    if (originalXml) {
+                        currentXml = originalXml
                     } else {
-                        // Fallback to export only if no cached XML
+                        // Fallback: use chartXML from ref if streaming didn't capture original
-                        currentXml = await onFetchChart(false)
+                        const cachedXML = chartXMLRef.current
+                        if (cachedXML) {
+                            currentXml = cachedXML
+                        } else {
+                            // Last resort: export from iframe
+                            currentXml = await onFetchChart(false)
+                        }
                     }
 
                     const { applyDiagramOperations } = await import(
@@ -370,6 +383,10 @@ ${currentXml}
 
 Please check the cell IDs and retry.`,
                         })
+                        // Clean up the shared original XML ref
+                        editDiagramOriginalXmlRef.current.delete(
+                            toolCall.toolCallId,
+                        )
                         return
                     }
 
@@ -393,6 +410,10 @@ ${currentXml}
 
 Please fix the operations to avoid structural issues.`,
                         })
+                        // Clean up the shared original XML ref
+                        editDiagramOriginalXmlRef.current.delete(
+                            toolCall.toolCallId,
+                        )
                         return
                     }
                     onExport()
@@ -401,6 +422,10 @@ Please fix the operations to avoid structural issues.`,
                         toolCallId: toolCall.toolCallId,
                         output: `Successfully applied ${operations.length} operation(s) to the diagram.`,
                     })
+                    // Clean up the shared original XML ref
+                    editDiagramOriginalXmlRef.current.delete(
+                        toolCall.toolCallId,
+                    )
                 } catch (error) {
                     console.error("[edit_diagram] Failed:", error)
 
@@ -420,6 +445,10 @@ ${currentXml || "No XML available"}
 
 Please check cell IDs and retry, or use display_diagram to regenerate.`,
                     })
+                    // Clean up the shared original XML ref even on error
+                    editDiagramOriginalXmlRef.current.delete(
+                        toolCall.toolCallId,
+                    )
                 }
             } else if (toolCall.toolName === "append_diagram") {
                 const { xml } = toolCall.input as { xml: string }
@@ -508,6 +537,32 @@ Continue from EXACTLY where you stopped.`,
             // Silence access code error in console since it's handled by UI
             if (!error.message.includes("Invalid or missing access code")) {
                 console.error("Chat error:", error)
+                // Debug: Log messages structure when error occurs
+                console.log("[onError] messages count:", messages.length)
+                messages.forEach((msg, idx) => {
+                    console.log(`[onError] Message ${idx}:`, {
+                        role: msg.role,
+                        partsCount: msg.parts?.length,
+                    })
+                    if (msg.parts) {
+                        msg.parts.forEach((part: any, partIdx: number) => {
+                            console.log(
+                                `[onError]   Part ${partIdx}:`,
+                                JSON.stringify({
+                                    type: part.type,
+                                    toolName: part.toolName,
+                                    hasInput: !!part.input,
+                                    inputType: typeof part.input,
+                                    inputKeys:
+                                        part.input &&
+                                        typeof part.input === "object"
+                                            ? Object.keys(part.input)
+                                            : null,
+                                }),
+                            )
+                        })
+                    }
+                })
             }
 
             // Translate technical errors into user-friendly messages
@@ -723,12 +778,10 @@ Continue from EXACTLY where you stopped.`,
         // Debounce: save after 1 second of no changes
         localStorageDebounceRef.current = setTimeout(() => {
             try {
-                console.time("perf:localStorage-messages")
                 localStorage.setItem(
                     STORAGE_MESSAGES_KEY,
                     JSON.stringify(messages),
                 )
-                console.timeEnd("perf:localStorage-messages")
             } catch (error) {
                 console.error("Failed to save messages to localStorage:", error)
             }
@@ -754,9 +807,7 @@ Continue from EXACTLY where you stopped.`,
 
         // Debounce: save after 1 second of no changes
         xmlStorageDebounceRef.current = setTimeout(() => {
-            console.time("perf:localStorage-xml")
             localStorage.setItem(STORAGE_DIAGRAM_XML_KEY, chartXML)
-            console.timeEnd("perf:localStorage-xml")
         }, LOCAL_STORAGE_DEBOUNCE_MS)
 
         return () => {
@@ -769,13 +820,11 @@ Continue from EXACTLY where you stopped.`,
     // Save XML snapshots to localStorage whenever they change
     const saveXmlSnapshots = useCallback(() => {
         try {
-            console.time("perf:localStorage-snapshots")
             const snapshotsArray = Array.from(xmlSnapshotsRef.current.entries())
             localStorage.setItem(
                 STORAGE_XML_SNAPSHOTS_KEY,
                 JSON.stringify(snapshotsArray),
             )
-            console.timeEnd("perf:localStorage-snapshots")
         } catch (error) {
             console.error(
                 "Failed to save XML snapshots to localStorage:",
@@ -1326,6 +1375,7 @@ Continue from EXACTLY where you stopped.`,
                     setInput={setInput}
                     setFiles={handleFileChange}
                     processedToolCallsRef={processedToolCallsRef}
+                    editDiagramOriginalXmlRef={editDiagramOriginalXmlRef}
                     sessionId={sessionId}
                     onRegenerate={handleRegenerate}
                     status={status}

contexts/diagram-context.tsx

@@ -86,20 +86,16 @@ export function DiagramProvider({ children }: { children: React.ReactNode }) {
         chart: string,
         skipValidation?: boolean,
     ): string | null => {
-        console.time("perf:loadDiagram")
         let xmlToLoad = chart
 
         // Validate XML structure before loading (unless skipped for internal use)
         if (!skipValidation) {
-            console.time("perf:loadDiagram-validation")
             const validation = validateAndFixXml(chart)
-            console.timeEnd("perf:loadDiagram-validation")
             if (!validation.valid) {
                 console.warn(
                     "[loadDiagram] Validation error:",
                     validation.error,
                 )
-                console.timeEnd("perf:loadDiagram")
                 return validation.error
             }
             // Use fixed XML if auto-fix was applied
@@ -116,14 +112,11 @@ export function DiagramProvider({ children }: { children: React.ReactNode }) {
         setChartXML(xmlToLoad)
 
         if (drawioRef.current) {
-            console.time("perf:drawio-iframe-load")
             drawioRef.current.load({
                 xml: xmlToLoad,
             })
-            console.timeEnd("perf:drawio-iframe-load")
         }
 
-        console.timeEnd("perf:loadDiagram")
         return null
     }
 

lib/utils.ts

@@ -743,8 +743,6 @@ function checkNestedMxCells(xml: string): string | null {
  * @returns null if valid, error message string if invalid
  */
 export function validateMxCellStructure(xml: string): string | null {
-    console.time("perf:validateMxCellStructure")
-    console.log(`perf:validateMxCellStructure XML size: ${xml.length} bytes`)
     // Size check for performance
     if (xml.length > MAX_XML_SIZE) {
         console.warn(
@@ -754,18 +752,10 @@ export function validateMxCellStructure(xml: string): string | null {
 
     // 0. First use DOM parser to catch syntax errors (most accurate)
     try {
-        console.time("perf:validate-DOMParser")
         const parser = new DOMParser()
         const doc = parser.parseFromString(xml, "text/xml")
-        console.timeEnd("perf:validate-DOMParser")
         const parseError = doc.querySelector("parsererror")
         if (parseError) {
-            const actualError = parseError.textContent || "Unknown parse error"
-            console.log(
-                "[validateMxCellStructure] DOMParser error:",
-                actualError,
-            )
-            console.timeEnd("perf:validateMxCellStructure")
             return `Invalid XML: The XML contains syntax errors (likely unescaped special characters like <, >, & in attribute values). Please escape special characters: use &lt; for <, &gt; for >, &amp; for &, &quot; for ". Regenerate the diagram with properly escaped values.`
         }
 
@@ -774,7 +764,6 @@ export function validateMxCellStructure(xml: string): string | null {
         for (const cell of allCells) {
             if (cell.parentElement?.tagName === "mxCell") {
                 const id = cell.getAttribute("id") || "unknown"
-                console.timeEnd("perf:validateMxCellStructure")
                 return `Invalid XML: Found nested mxCell (id="${id}"). Cells should be siblings, not nested inside other mxCell elements.`
             }
         }
@@ -788,16 +777,12 @@ export function validateMxCellStructure(xml: string): string | null {
 
     // 1. Check for CDATA wrapper (invalid at document root)
     if (/^\s*<!\[CDATA\[/.test(xml)) {
-        console.timeEnd("perf:validateMxCellStructure")
         return "Invalid XML: XML is wrapped in CDATA section - remove <![CDATA[ from start and ]]> from end"
     }
 
     // 2. Check for duplicate structural attributes
-    console.time("perf:checkDuplicateAttributes")
     const dupAttrError = checkDuplicateAttributes(xml)
-    console.timeEnd("perf:checkDuplicateAttributes")
     if (dupAttrError) {
-        console.timeEnd("perf:validateMxCellStructure")
         return dupAttrError
     }
 
@@ -807,33 +792,25 @@ export function validateMxCellStructure(xml: string): string | null {
     while ((attrValMatch = attrValuePattern.exec(xml)) !== null) {
         const value = attrValMatch[1]
         if (/</.test(value) && !/&lt;/.test(value)) {
-            console.timeEnd("perf:validateMxCellStructure")
             return "Invalid XML: Unescaped < character in attribute values. Replace < with &lt;"
         }
     }
 
     // 4. Check for duplicate IDs
-    console.time("perf:checkDuplicateIds")
     const dupIdError = checkDuplicateIds(xml)
-    console.timeEnd("perf:checkDuplicateIds")
     if (dupIdError) {
-        console.timeEnd("perf:validateMxCellStructure")
         return dupIdError
     }
 
     // 5. Check for tag mismatches
-    console.time("perf:checkTagMismatches")
     const tagMismatchError = checkTagMismatches(xml)
-    console.timeEnd("perf:checkTagMismatches")
     if (tagMismatchError) {
-        console.timeEnd("perf:validateMxCellStructure")
         return tagMismatchError
     }
 
     // 6. Check invalid character references
     const charRefError = checkCharacterReferences(xml)
     if (charRefError) {
-        console.timeEnd("perf:validateMxCellStructure")
         return charRefError
     }
 
@@ -842,7 +819,6 @@ export function validateMxCellStructure(xml: string): string | null {
     let commentMatch
     while ((commentMatch = commentPattern.exec(xml)) !== null) {
         if (/--/.test(commentMatch[1])) {
-            console.timeEnd("perf:validateMxCellStructure")
             return "Invalid XML: Comment contains -- (double hyphen) which is not allowed"
         }
     }
@@ -850,24 +826,20 @@ export function validateMxCellStructure(xml: string): string | null {
     // 8. Check for unescaped entity references and invalid entity names
     const entityError = checkEntityReferences(xml)
     if (entityError) {
-        console.timeEnd("perf:validateMxCellStructure")
         return entityError
     }
 
     // 9. Check for empty id attributes on mxCell
     if (/<mxCell[^>]*\sid\s*=\s*["']\s*["'][^>]*>/g.test(xml)) {
-        console.timeEnd("perf:validateMxCellStructure")
         return "Invalid XML: Found mxCell element(s) with empty id attribute"
     }
 
     // 10. Check for nested mxCell tags
     const nestedCellError = checkNestedMxCells(xml)
     if (nestedCellError) {
-        console.timeEnd("perf:validateMxCellStructure")
         return nestedCellError
     }
 
-    console.timeEnd("perf:validateMxCellStructure")
     return null
 }