diff --git a/src/lib/ComfyGraphCanvas.ts b/src/lib/ComfyGraphCanvas.ts
index c3b792e..72a7107 100644
--- a/src/lib/ComfyGraphCanvas.ts
+++ b/src/lib/ComfyGraphCanvas.ts
@@ -1,14 +1,15 @@
-import { BuiltInSlotShape, LGraphCanvas, LGraphNode, LLink, LiteGraph, NodeMode, Subgraph, TitleMode, type ContextMenuItem, type IContextMenuItem, type NodeID, type Vector2, type Vector4, type MouseEventExt, ContextMenu, type SerializedLGraphNode } from "@litegraph-ts/core";
+import { BuiltInSlotShape, ContextMenu, LGraphCanvas, LGraphNode, LLink, LiteGraph, NodeMode, Subgraph, TitleMode, type ContextMenuItem, type IContextMenuItem, type MouseEventExt, type NodeID, type Vector2, type Vector4, LGraph, type SlotIndex, type SlotNameOrIndex } from "@litegraph-ts/core";
 import { get, type Unsubscriber } from "svelte/store";
+import { createTemplate, serializeTemplate, type ComfyBoxTemplate, type SerializedComfyBoxTemplate } from "./ComfyBoxTemplate";
 import type ComfyGraph from "./ComfyGraph";
+import type { ComfyGraphErrorLocation, ComfyGraphErrors, ComfyNodeErrors } from "./apiErrors";
 import type ComfyApp from "./components/ComfyApp";
 import { ComfyReroute } from "./nodes";
+import notify from "./notify";
 import layoutStates, { type ContainerLayout } from "./stores/layoutStates";
 import queueState from "./stores/queueState";
 import selectionState from "./stores/selectionState";
 import templateState from "./stores/templateState";
-import { createTemplate, type ComfyBoxTemplate, serializeTemplate, type SerializedComfyBoxTemplate } from "./ComfyBoxTemplate";
-import notify from "./notify";
 import { calcNodesBoundingBox } from "./utils";
 
 export type SerializedGraphCanvasState = {
@@ -20,11 +21,22 @@ export default class ComfyGraphCanvas extends LGraphCanvas {
     app: ComfyApp | null;
     private _unsubscribe: Unsubscriber;
     isExportingSVG: boolean = false;
+    activeErrors?: ComfyGraphErrors = null;
+    blinkError: ComfyGraphErrorLocation | null = null;
+    blinkErrorTime: number = 0;
+    highlightNodeAndInput: [LGraphNode, number] | null = null;
 
     get comfyGraph(): ComfyGraph | null {
         return this.graph as ComfyGraph;
     }
 
+    clearErrors() {
+        this.activeErrors = null;
+        this.blinkError = null;
+        this.blinkErrorTime = 0;
+        this.highlightNodeAndInput = null;
+    }
+
     constructor(
         app: ComfyApp,
         canvas: HTMLCanvasElement | string,
@@ -90,10 +102,18 @@ export default class ComfyGraphCanvas extends LGraphCanvas {
 
         let state = get(queueState);
         let ss = get(selectionState);
-        const isRunningNode = node.id === state.runningNodeID
+
+        const isRunningNode = node.id == state.runningNodeID
+        const nodeErrors = this.activeErrors?.errorsByID[node.id];
+        const isHighlightedNode = this.highlightNodeAndInput && this.highlightNodeAndInput[0].id === node.id;
+
+        if (this.blinkErrorTime > 0) {
+            this.blinkErrorTime -= this.graph.elapsed_time;
+        }
 
         let color = null;
         let thickness = 1;
+        let blink = false;
         // if (this._selectedNodes.has(node.id)) {
         //     color = "yellow";
         //     thickness = 5;
@@ -104,6 +124,29 @@ export default class ComfyGraphCanvas extends LGraphCanvas {
         else if (isRunningNode) {
             color = "#0f0";
         }
+        else if (nodeErrors) {
+            const hasExecutionError = nodeErrors.find(e => e.errorType === "execution");
+            if (hasExecutionError) {
+                blink = true;
+                color = "#f0f";
+            }
+            else {
+                color = "red";
+            }
+            thickness = 2
+        }
+        else if (isHighlightedNode) {
+            color = "cyan";
+            thickness = 2
+        }
+
+        if (blink) {
+            if (nodeErrors && nodeErrors.includes(this.blinkError) && this.blinkErrorTime > 0) {
+                if ((Math.floor(this.blinkErrorTime / 2)) % 2 === 0) {
+                    color = null;
+                }
+            }
+        }
 
         if (color) {
             this.drawNodeOutline(node, ctx, size, mouseOver, fgColor, bgColor, color, thickness)
@@ -114,6 +157,54 @@ export default class ComfyGraphCanvas extends LGraphCanvas {
             ctx.fillRect(0, 0, size[0] * (state.progress.value / state.progress.max), 6);
             ctx.fillStyle = bgColor;
         }
+
+        if (nodeErrors) {
+            this.drawFailedValidationInputs(node, nodeErrors, color, ctx);
+        }
+
+        if (isHighlightedNode) {
+            let draw = true;
+            if (this.blinkErrorTime > 0) {
+                if ((Math.floor(this.blinkErrorTime / 2)) % 2 === 0) {
+                    draw = false;
+                }
+            }
+            if (draw) {
+                const [node, inputSlot] = this.highlightNodeAndInput;
+                ctx.lineWidth = 2;
+                ctx.strokeStyle = color;
+                this.highlightNodeInput(node, inputSlot, ctx);
+            }
+        }
+    }
+
+    private drawFailedValidationInputs(node: LGraphNode, errors: ComfyGraphErrorLocation[], color: string, ctx: CanvasRenderingContext2D) {
+        ctx.lineWidth = 2;
+        ctx.strokeStyle = color || "red";
+        for (const errorLocation of errors) {
+            if (errorLocation.input != null) {
+                if (errorLocation === this.blinkError && this.blinkErrorTime > 0) {
+                    if ((Math.floor(this.blinkErrorTime / 2)) % 2 === 0) {
+                        continue;
+                    }
+                }
+                this.highlightNodeInput(node, errorLocation.input.name, ctx);
+            }
+        }
+    }
+
+    private highlightNodeInput(node: LGraphNode, inputSlot: SlotNameOrIndex, ctx: CanvasRenderingContext2D) {
+        let inputIndex: number;
+        if (typeof inputSlot === "number")
+            inputIndex = inputSlot
+        else
+            inputIndex = node.findInputSlotIndexByName(inputSlot)
+        if (inputIndex !== -1) {
+            let pos = node.getConnectionPos(true, inputIndex);
+            ctx.beginPath();
+            ctx.arc(pos[0] - node.pos[0], pos[1] - node.pos[1], 12, 0, 2 * Math.PI, false)
+            ctx.stroke();
+        }
     }
 
     private drawNodeOutline(node: LGraphNode, ctx: CanvasRenderingContext2D, size: Vector2, mouseOver: boolean, fgColor: string, bgColor: string, outlineColor: string, outlineThickness: number) {
@@ -568,4 +659,61 @@ export default class ComfyGraphCanvas extends LGraphCanvas {
         }
         return false;
     }
+
+    jumpToFirstError() {
+        this.jumpToError(0);
+    }
+
+    jumpToError(index: number | ComfyGraphErrorLocation) {
+        if (this.activeErrors == null) {
+            return;
+        }
+
+        let error;
+        if (typeof index === "number") {
+            error = this.activeErrors.errors[index]
+        }
+        else {
+            error = index;
+        }
+
+        if (error == null) {
+            return;
+        }
+
+        const rootGraph = this.graph.getRootGraph()
+        if (rootGraph == null) {
+            return
+        }
+
+        const node = rootGraph.getNodeByIdRecursive(error.nodeID);
+        if (node == null) {
+            notify(`Couldn't find node '${error.comfyNodeType}' (${error.nodeID})`, { type: "warning" })
+            return
+        }
+
+        this.jumpToNode(node)
+
+        this.highlightNodeAndInput = null;
+        this.blinkError = error;
+        this.blinkErrorTime = 20;
+    }
+
+    jumpToNode(node: LGraphNode) {
+        this.closeAllSubgraphs();
+
+        const subgraphs = Array.from(node.iterateParentSubgraphNodes()).reverse();
+
+        for (const subgraph of subgraphs) {
+            this.openSubgraph(subgraph.subgraph)
+        }
+
+        this.centerOnNode(node);
+    }
+
+    jumpToNodeAndInput(node: LGraphNode, slotIndex: number) {
+        this.jumpToNode(node);
+        this.highlightNodeAndInput = [node, slotIndex];
+        this.blinkErrorTime = 20;
+    }
 }
diff --git a/src/lib/api.ts b/src/lib/api.ts
index 708968b..7d7f47d 100644
--- a/src/lib/api.ts
+++ b/src/lib/api.ts
@@ -1,11 +1,12 @@
-import type { Progress, SerializedPrompt, SerializedPromptInputsForNode, SerializedPromptInputsAll, SerializedPromptOutputs, SerializedAppState } from "./components/ComfyApp";
+import type { Progress, SerializedPrompt, SerializedPromptInputsForNode, SerializedPromptInputsAll, SerializedPromptOutputs, SerializedAppState, SerializedPromptInput, SerializedPromptInputLink } from "./components/ComfyApp";
 import type TypedEmitter from "typed-emitter";
 import EventEmitter from "events";
 import type { ComfyImageLocation } from "$lib/utils";
 import type { SerializedLGraph, UUID } from "@litegraph-ts/core";
 import type { SerializedLayoutState } from "./stores/layoutStates";
-import type { ComfyNodeDef } from "./ComfyNodeDef";
+import type { ComfyNodeDef, ComfyNodeDefInput } from "./ComfyNodeDef";
 import type { WorkflowInstID } from "./stores/workflowState";
+import type { ComfyAPIPromptErrorResponse } from "./apiErrors";
 
 export type ComfyPromptRequest = {
     client_id?: string,
@@ -43,11 +44,12 @@ export type ComfyAPIHistoryItem = [
     ComfyNodeID[]  // good outputs
 ]
 
-export type ComfyAPIPromptResponse = {
-    promptID?: PromptID,
-    error?: string
+export type ComfyAPIPromptSuccessResponse = {
+    promptID: PromptID
 }
 
+export type ComfyAPIPromptResponse = ComfyAPIPromptSuccessResponse | ComfyAPIPromptErrorResponse
+
 export type ComfyAPIHistoryEntry = {
     prompt: ComfyAPIHistoryItem,
     outputs: SerializedPromptOutputs
@@ -92,7 +94,8 @@ type ComfyAPIEvents = {
     executed: (promptID: PromptID, nodeID: ComfyNodeID, output: SerializedPromptOutputs) => void,
     execution_start: (promptID: PromptID) => void,
     execution_cached: (promptID: PromptID, nodes: ComfyNodeID[]) => void,
-    execution_error: (promptID: PromptID, message: string) => void,
+    execution_interrupted: (error: ComfyInterruptedError) => void,
+    execution_error: (error: ComfyExecutionError) => void,
 }
 
 export default class ComfyAPI {
@@ -201,8 +204,11 @@ export default class ComfyAPI {
                     case "execution_cached":
                         this.eventBus.emit("execution_cached", msg.data.prompt_id, msg.data.nodes);
                         break;
+                    case "execution_interrupted":
+                        this.eventBus.emit("execution_interrupted", msg.data);
+                        break;
                     case "execution_error":
-                        this.eventBus.emit("execution_error", msg.data.prompt_id, msg.data.message);
+                        this.eventBus.emit("execution_error", msg.data);
                         break;
                     default:
                         console.warn("Unhandled message:", event.data);
diff --git a/src/lib/apiErrors.ts b/src/lib/apiErrors.ts
new file mode 100644
index 0000000..e631cbc
--- /dev/null
+++ b/src/lib/apiErrors.ts
@@ -0,0 +1,270 @@
+import type { NodeID } from "@litegraph-ts/core"
+import type { ComfyNodeDefInput } from "./ComfyNodeDef"
+import type { ComfyNodeID, PromptID } from "./api"
+import type { SerializedPromptInputLink } from "./components/ComfyApp"
+import type { WorkflowError, WorkflowInstID } from "./stores/workflowState"
+import { exclude_internal_props } from "svelte/internal"
+import type ComfyGraphCanvas from "./ComfyGraphCanvas"
+import type { QueueEntry } from "./stores/queueState"
+
+enum ComfyPromptErrorType {
+    NoOutputs = "prompt_no_outputs",
+    OutputsFailedValidation = "prompt_outputs_failed_validation",
+}
+
+export interface ComfyPromptError<T = any> {
+    type: ComfyPromptErrorType,
+    message: string,
+    details: string,
+    extra_info: T
+}
+
+export interface CPENoOutputs extends ComfyPromptError {
+    type: ComfyPromptErrorType.NoOutputs
+}
+
+export interface CPEOutputsFailedValidation extends ComfyPromptError {
+    type: ComfyPromptErrorType.OutputsFailedValidation
+}
+
+export enum ComfyNodeErrorType {
+    RequiredInputMissing = "required_input_missing",
+    BadLinkedInput = "bad_linked_input",
+    ReturnTypeMismatch = "return_type_mismatch",
+    InvalidInputType = "invalid_input_type",
+    ValueSmallerThanMin = "value_smaller_than_min",
+    ValueBiggerThanMax = "value_bigger_than_max",
+    CustomValidationFailed = "custom_validation_failed",
+    ValueNotInList = "value_not_in_list",
+    ExceptionDuringValidation = "exception_during_validation",
+    ExceptionDuringInnerValidation = "exception_during_inner_validation",
+}
+
+export interface ComfyNodeError<T = any> {
+    type: ComfyNodeErrorType,
+    message: string,
+    details: string,
+    extra_info: T
+}
+
+export type ComfyNodeErrors = {
+    errors: ComfyNodeError[],
+    dependent_outputs: ComfyNodeID[],
+    class_type: string
+}
+
+export type InputWithValue = {
+    input_name: string,
+    input_config: ComfyNodeDefInput,
+    received_value: any
+}
+
+function isInputWithValue(param: any): param is InputWithValue {
+    return param && "input_name" in param;
+}
+
+export type InputWithValueAndException = InputWithValue & {
+    exception_message: string
+}
+
+export type InputWithLinkedNode = {
+    input_name: string,
+    input_config: ComfyNodeDefInput,
+    linked_node: SerializedPromptInputLink
+}
+
+export type ValidationException = {
+    exception_type: string,
+    traceback: string[]
+}
+
+function isValidationException(param: any): param is ValidationException {
+    return param && "exception_type" in param && "traceback" in param;
+}
+
+export interface CNERequiredInputMissing extends ComfyNodeError<{ input_name: string }> {
+    type: ComfyNodeErrorType.RequiredInputMissing
+}
+
+export interface CNEBadLinkedInput extends ComfyNodeError<InputWithValue> {
+    type: ComfyNodeErrorType.BadLinkedInput
+}
+
+export interface CNEReturnTypeMismatch extends ComfyNodeError<InputWithLinkedNode & { received_type: string }> {
+    type: ComfyNodeErrorType.ReturnTypeMismatch
+}
+
+export interface CNEInvalidInputType extends ComfyNodeError<InputWithValue & { exception_message: string }> {
+    type: ComfyNodeErrorType.InvalidInputType
+}
+
+export interface CNEValueSmallerThanMin extends ComfyNodeError<InputWithValue> {
+    type: ComfyNodeErrorType.ValueSmallerThanMin
+}
+
+export interface CNEValueBiggerThanMax extends ComfyNodeError<InputWithValue> {
+    type: ComfyNodeErrorType.ValueBiggerThanMax
+}
+
+export interface CNECustomValidationFailed extends ComfyNodeError<InputWithValue> {
+    type: ComfyNodeErrorType.CustomValidationFailed
+}
+
+export interface CNEValueNotInList extends ComfyNodeError<InputWithValue> {
+    type: ComfyNodeErrorType.ValueNotInList
+}
+
+export interface CNEExceptionDuringValidation extends ComfyNodeError<ValidationException> {
+    type: ComfyNodeErrorType.ExceptionDuringValidation
+}
+
+export interface CNEExceptionDuringInnerValidation extends ComfyNodeError<InputWithLinkedNode & ValidationException> {
+    type: ComfyNodeErrorType.ExceptionDuringInnerValidation
+}
+
+export type ComfyAPIPromptErrorResponse = {
+    error: ComfyPromptError,
+    node_errors: Record<ComfyNodeID, ComfyNodeErrors>,
+}
+
+export type ComfyInterruptedError = {
+    prompt_id: PromptID,
+    node_id: ComfyNodeID,
+    node_type: string,
+    executed: ComfyNodeID[]
+}
+
+export type ComfyExecutionError = ComfyInterruptedError & {
+    exception_message: string,
+    exception_type: string,
+    traceback: string[],
+    current_inputs: any[],
+    current_outputs: any[][],
+}
+
+export function formatValidationError(error: ComfyAPIPromptErrorResponse) {
+    return `${error.error.message}: ${error.error.details}`
+}
+
+export function formatExecutionError(error: ComfyExecutionError) {
+    return error.exception_message
+}
+
+export type ComfyGraphErrorInput = {
+    name: string,
+    config?: ComfyNodeDefInput,
+
+    receivedValue?: any,
+    receivedType?: string,
+    linkedNode?: SerializedPromptInputLink
+}
+
+export type ComfyGraphErrorLocation = {
+    workflowID: WorkflowInstID,
+    nodeID: NodeID,
+    comfyNodeType: string,
+    errorType: ComfyNodeErrorType | "execution",
+    message: string,
+    dependentOutputs: NodeID[],
+    queueEntry: QueueEntry,
+
+    input?: ComfyGraphErrorInput,
+
+    exceptionMessage?: string,
+    exceptionType?: string,
+    traceback?: string[],
+
+    inputValues?: any[],
+    outputValues?: any[][],
+}
+
+export type ComfyGraphErrors = {
+    message: string,
+    errors: ComfyGraphErrorLocation[],
+    errorsByID: Record<NodeID, ComfyGraphErrorLocation[]>
+}
+
+export function validationErrorToGraphErrors(workflowID: WorkflowInstID, validationError: ComfyAPIPromptErrorResponse, queueEntry: QueueEntry): ComfyGraphErrors {
+    const errorsByID: Record<NodeID, ComfyGraphErrorLocation[]> = {}
+
+    for (const [nodeID, nodeErrors] of Object.entries(validationError.node_errors)) {
+        errorsByID[nodeID] = nodeErrors.errors.map(e => {
+            const loc: ComfyGraphErrorLocation = {
+                workflowID,
+                nodeID,
+                comfyNodeType: nodeErrors.class_type,
+                errorType: e.type,
+                message: e.message,
+                dependentOutputs: nodeErrors.dependent_outputs,
+                queueEntry
+            }
+
+            if (isInputWithValue(e.extra_info)) {
+                loc.input = {
+                    name: e.extra_info.input_name,
+                    config: e.extra_info.input_config,
+                    receivedValue: e.extra_info.received_value
+                }
+
+                if ("received_type" in e.extra_info) {
+                    loc.input.receivedType = e.extra_info.received_type as string;
+                }
+                if ("linked_node" in e.extra_info) {
+                    loc.input.linkedNode = e.extra_info.linked_node as SerializedPromptInputLink;
+                }
+            }
+
+            if ("exception_message" in e.extra_info) {
+                loc.exceptionMessage = e.extra_info.exception_message as "string"
+            }
+
+            if (isValidationException(e.extra_info)) {
+                loc.exceptionType = e.extra_info.exception_type;
+                loc.traceback = e.extra_info.traceback;
+            }
+
+            return loc;
+        })
+    }
+
+    return {
+        message: validationError.error.message,
+        errors: Object.values(errorsByID).flatMap(e => e),
+        errorsByID
+    }
+}
+
+export function executionErrorToGraphErrors(workflowID: WorkflowInstID, executionError: ComfyExecutionError, queueEntry: QueueEntry): ComfyGraphErrors {
+    const errorsByID: Record<NodeID, ComfyGraphErrorLocation[]> = {}
+
+    errorsByID[executionError.node_id] = [{
+        workflowID,
+        nodeID: executionError.node_id,
+        comfyNodeType: executionError.node_type,
+        errorType: "execution",
+        message: executionError.exception_message,
+        dependentOutputs: [], // TODO
+        queueEntry,
+
+        exceptionMessage: executionError.exception_message,
+        exceptionType: executionError.exception_type,
+        traceback: executionError.traceback,
+        inputValues: executionError.current_inputs,
+        outputValues: executionError.current_outputs,
+    }]
+
+    return {
+        message: executionError.exception_message,
+        errors: Object.values(errorsByID).flatMap(e => e),
+        errorsByID
+    }
+}
+
+export function workflowErrorToGraphErrors(workflowID: WorkflowInstID, workflowError: WorkflowError, queueEntry: QueueEntry): ComfyGraphErrors {
+    if (workflowError.type === "validation") {
+        return validationErrorToGraphErrors(workflowID, workflowError.error, queueEntry)
+    }
+    else {
+        return executionErrorToGraphErrors(workflowID, workflowError.error, queueEntry)
+    }
+}
diff --git a/src/lib/components/ComfyApp.ts b/src/lib/components/ComfyApp.ts
index 551abac..9f905be 100644
--- a/src/lib/components/ComfyApp.ts
+++ b/src/lib/components/ComfyApp.ts
@@ -1,4 +1,4 @@
-import ComfyAPI, { type ComfyAPIStatusResponse, type ComfyBoxPromptExtraData, type ComfyNodeID, type ComfyPromptRequest, type PromptID, type QueueItemType } from "$lib/api";
+import ComfyAPI, { type iomfyAPIPromptResponse, type ComfyAPIStatusResponse, type ComfyBoxPromptExtraData, type ComfyNodeID, type ComfyPromptRequest, type PromptID, type QueueItemType } from "$lib/api";
 import { parsePNGMetadata } from "$lib/pnginfo";
 import { BuiltInSlotType, LGraphCanvas, LGraphNode, LiteGraph, NodeMode, type INodeInputSlot, type LGraphNodeConstructor, type NodeID, type NodeTypeOpts, type SerializedLGraph, type SlotIndex } from "@litegraph-ts/core";
 import A1111PromptModal from "./modal/A1111PromptModal.svelte";
@@ -38,6 +38,7 @@ import ComfyPromptSerializer, { isActiveBackendNode, nodeHasTag, UpstreamNodeLoc
 import DanbooruTags from "$lib/DanbooruTags";
 import { deserializeTemplateFromSVG, type SerializedComfyBoxTemplate } from "$lib/ComfyBoxTemplate";
 import templateState from "$lib/stores/templateState";
+import { formatValidationError, type ComfyAPIPromptErrorResponse, formatExecutionError, type ComfyExecutionError } from "$lib/apiErrors";
 
 export const COMFYBOX_SERIAL_VERSION = 1;
 
@@ -91,7 +92,8 @@ export type SerializedAppState = {
 }
 
 /** [link_origin, link_slot_index] | input_value */
-export type SerializedPromptInput = [ComfyNodeID, number] | any
+export type SerializedPromptInputLink = [ComfyNodeID, number]
+export type SerializedPromptInput = SerializedPromptInputLink | any
 
 export type SerializedPromptInputs = Record<string, SerializedPromptInput>;
 
@@ -307,7 +309,7 @@ export default class ComfyApp {
             if (errors && errors.length > 0)
                 error = "Error(s) loading builtin templates:\n" + errors.join("\n");
 
-            console.log(`Loaded {templates.length} builtin templates.`);
+            console.log(`Loaded ${templates.length} builtin templates.`);
 
             return [templates, error]
         })
@@ -597,9 +599,33 @@ export default class ComfyApp {
             queueState.executionCached(promptID, nodes)
         });
 
-        this.api.addEventListener("execution_error", (promptID: PromptID, message: string) => {
-            queueState.executionError(promptID, message)
-            notify(`Execution error: ${message}`, { type: "error", timeout: 10000 })
+        this.api.addEventListener("execution_error", (error: ComfyExecutionError) => {
+            const completedEntry = queueState.executionError(error)
+            let workflow: ComfyBoxWorkflow | null;
+            if (completedEntry) {
+                const workflowID = completedEntry.entry.extraData.workflowID;
+                if (workflowID) {
+                    workflow = workflowState.getWorkflow(workflowID)
+                }
+            }
+
+            if (workflow) {
+                workflowState.executionError(workflow.id, error.prompt_id)
+                notify(
+                    `Execution error in workflow "${workflow.attrs.title}".\nClick for details.`,
+                    {
+                        type: "error",
+                        showBar: true,
+                        timeout: 15 * 1000,
+                        onClick: () => {
+                            uiState.update(s => { s.activeError = error.prompt_id; return s })
+                        }
+                    })
+            }
+            else {
+                const message = formatExecutionError(error);
+                notify(`Execution error: ${message}`, { type: "error", timeout: 10000 })
+            }
         });
 
         this.api.init();
@@ -1006,8 +1032,9 @@ export default class ComfyApp {
                         thumbnails
                     }
 
-                    let error: string | null = null;
-                    let promptID: PromptID | null = null;
+                    let error: ComfyAPIPromptErrorResponse | null = null;
+                    let errorMes: string | null = null;
+                    let errorPromptID: PromptID | null = null;
 
                     const request: ComfyPromptRequest = {
                         number: num,
@@ -1017,22 +1044,36 @@ export default class ComfyApp {
 
                     try {
                         const response = await this.api.queuePrompt(request);
-                        if (response.error != null) {
+                        if ("error" in response) {
                             error = response;
+                            errorMes = formatValidationError(error)
+                            errorPromptID = queueState.promptError(workflow.id, response, p, extraData)
+                            workflowState.promptError(workflow.id, errorPromptID)
                         }
                         else {
                             queueState.afterQueued(workflow.id, response.promptID, num, p.output, extraData)
+                            workflowState.afterQueued(workflow.id, response.promptID, p, extraData)
                         }
                     } catch (err) {
-                        error = err?.toString();
+                        errorMes = err?.toString();
                     }
 
                     if (error != null) {
-                        const mes: any = error;
-                        notify(`Error queuing prompt: \n${mes} `, { type: "error" })
+                        notify(
+                            `Prompt validation failed.\nClick for details.`,
+                            {
+                                type: "error",
+                                showBar: true,
+                                timeout: 1000 * 15,
+                                onClick: () => {
+                                    uiState.update(s => { s.activeError = errorPromptID; return s })
+                                }
+                            })
                         console.error(graphToGraphVis(workflow.graph))
                         console.error(promptToGraphVis(p))
                         console.error("Error queuing prompt", error, num, p)
+                    }
+                    else if (errorMes != null) {
                         break;
                     }
 
@@ -1254,7 +1295,7 @@ export default class ComfyApp {
             let defaultValue = null;
             if (foundInput != null) {
                 const comfyInput = foundInput as IComfyInputSlot;
-                console.warn("[refreshComboInNodes] found frontend config:", node.title, node.type, comfyInput.config.values)
+                console.warn("[refreshComboInNodes] found frontend config:", node.title, node.type, comfyInput.config.values.length)
                 values = comfyInput.config.values;
                 defaultValue = comfyInput.config.defaultValue;
             }
diff --git a/src/lib/components/ComfyBoxWorkflowsView.svelte b/src/lib/components/ComfyBoxWorkflowsView.svelte
index 8cc5aa1..816dc39 100644
--- a/src/lib/components/ComfyBoxWorkflowsView.svelte
+++ b/src/lib/components/ComfyBoxWorkflowsView.svelte
@@ -1,3 +1,7 @@
+<script context="module" lang="ts">
+ export const WORKFLOWS_VIEW: any = {}
+</script>
+
 <script lang="ts">
  import { Pane, Splitpanes } from 'svelte-splitpanes';
  import { PlusSquareDotted } from 'svelte-bootstrap-icons';
@@ -12,12 +16,15 @@
  import workflowState, { ComfyBoxWorkflow, type WorkflowInstID } from "$lib/stores/workflowState";
  import selectionState from "$lib/stores/selectionState";
  import type ComfyApp from './ComfyApp';
- import { onMount } from "svelte";
+ import { onMount, setContext, tick } from "svelte";
  import { dndzone, SHADOW_ITEM_MARKER_PROPERTY_NAME, SHADOW_PLACEHOLDER_ITEM_ID } from 'svelte-dnd-action';
  import { fade } from 'svelte/transition';
  import { cubicIn } from 'svelte/easing';
  import { truncateString } from '$lib/utils';
  import ComfyPaneView from './ComfyPaneView.svelte';
+ import type { PromptID } from '$lib/api';
+ import queueState, { type CompletedQueueEntry } from '$lib/stores/queueState';
+ import { workflowErrorToGraphErrors } from '$lib/apiErrors';
 
  export let app: ComfyApp;
  export let uiTheme: string = "gradio-dark" // TODO config
@@ -44,6 +51,8 @@
      }
      );
      refreshView();
+
+     lastError = null;
  })
 
  async function doRefreshCombos() {
@@ -70,18 +79,22 @@
 
  let graphSize = 0;
 
- $: if (containerElem) {
+ function getGraphPane(): HTMLDivElement | null {
      const canvas = containerElem.querySelector<HTMLDivElement>("#graph-canvas")
-     if (canvas) {
-         const paneNode = canvas.closest(".splitpanes__pane")
-         if (paneNode) {
-             (paneNode as HTMLElement).ontransitionstart = () => {
-                 $interfaceState.graphTransitioning = true
-             }
-             (paneNode as HTMLElement).ontransitionend = () => {
-                 $interfaceState.graphTransitioning = false
-                 app.resizeCanvas()
-             }
+     if (!canvas)
+         return null;
+     return canvas.closest(".splitpanes__pane")
+ }
+
+ $: if (containerElem) {
+     const paneNode = getGraphPane();
+     if (paneNode) {
+         (paneNode as HTMLElement).ontransitionstart = () => {
+             $interfaceState.graphTransitioning = true
+         }
+         (paneNode as HTMLElement).ontransitionend = () => {
+             $interfaceState.graphTransitioning = false
+             app.resizeCanvas()
          }
      }
  }
@@ -191,6 +204,77 @@
          return s;
      })
  };
+
+ let lastError: PromptID | null = null;
+
+ $: {
+     const activeError = $uiState.activeError
+     if (activeError != lastError) {
+         if (activeError != null) {
+             showError(activeError)
+         }
+         else {
+             hideError();
+         }
+         lastError = $uiState.activeError;
+     }
+ }
+
+ async function showError(promptIDWithError: PromptID) {
+     hideError();
+
+     const completed: CompletedQueueEntry = get($queueState.queueCompleted).find(e => e.entry.promptID === promptIDWithError);
+     if (!completed || !completed.error) {
+         console.error("Prompt with error not found!", promptIDWithError);
+         return
+     }
+
+     const workflow = workflowState.getWorkflow(completed.entry.extraData.workflowID)
+     if (workflow == null) {
+         console.error("Workflow with error not found!", promptIDWithError, completed);
+         return
+     }
+
+     workflowState.setActiveWorkflow(app.lCanvas, workflow.id);
+     $uiState.activeError = promptIDWithError;
+     lastError = $uiState.activeError;
+
+     const jumpToError = () => {
+         app.resizeCanvas();
+         app.lCanvas.draw(true, true);
+
+         app.lCanvas.activeErrors = workflowErrorToGraphErrors(workflow.id, completed.error, completed.entry);
+         app.lCanvas.jumpToFirstError();
+     }
+
+     const newGraphSize = Math.max(50, graphSize);
+     const willOpenPane = newGraphSize != graphSize
+     graphSize = newGraphSize
+
+     if (willOpenPane) {
+         const graphPane = getGraphPane();
+         if (graphPane) {
+             graphPane.addEventListener("transitionend", jumpToError, { once: true })
+             await tick()
+         }
+         else {
+             jumpToError()
+         }
+     }
+     else {
+         jumpToError()
+     }
+ }
+
+ function hideError() {
+     if (app?.lCanvas) {
+         app.lCanvas.clearErrors();
+     }
+ }
+
+ setContext(WORKFLOWS_VIEW, {
+     showError
+ });
 </script>
 
 <div id="comfy-content" bind:this={containerElem} class:loading>
diff --git a/src/lib/components/ComfyGraphErrorList.svelte b/src/lib/components/ComfyGraphErrorList.svelte
new file mode 100644
index 0000000..ad68d26
--- /dev/null
+++ b/src/lib/components/ComfyGraphErrorList.svelte
@@ -0,0 +1,299 @@
+<script lang="ts">
+ import { ComfyNodeErrorType, type ComfyGraphErrorLocation, type ComfyGraphErrors } from "$lib/apiErrors";
+ import type ComfyApp from "./ComfyApp";
+ import Accordion from "./gradio/app/Accordion.svelte";
+ import uiState from '$lib/stores/uiState';
+ import type { ComfyNodeDefInputType } from "$lib/ComfyNodeDef";
+ import type { INodeInputSlot, LGraphNode, Subgraph } from "@litegraph-ts/core";
+ import { UpstreamNodeLocator } from "./ComfyPromptSerializer";
+ import JsonView from "./JsonView.svelte";
+
+ export let app: ComfyApp;
+ export let errors: ComfyGraphErrors;
+
+ function closeList() {
+     app.lCanvas.clearErrors();
+     $uiState.activeError = null;
+ }
+
+ function getParentNode(error: ComfyGraphErrorLocation): Subgraph | null {
+     const node = app.lCanvas.graph.getNodeByIdRecursive(error.nodeID);
+     if (node == null || !node.graph._is_subgraph)
+         return null;
+
+     return node.graph._subgraph_node
+ }
+
+ function canJumpToDisconnectedInput(error: ComfyGraphErrorLocation): boolean {
+     return error.errorType === ComfyNodeErrorType.RequiredInputMissing && error.input != null;
+ }
+
+ function jumpToDisconnectedInput(error: ComfyGraphErrorLocation) {
+     if (error.errorType !== ComfyNodeErrorType.RequiredInputMissing || error.input == null) {
+         return
+     }
+
+     const node = app.lCanvas.graph.getNodeByIdRecursive(error.nodeID);
+
+     const inputIndex =node.findInputSlotIndexByName(error.input.name);
+     if (inputIndex === -1) {
+         return
+     }
+
+     // TODO multiple tags?
+     const tag: string | null = error.queueEntry.extraData.extra_pnginfo.comfyBoxPrompt.subgraphs[0];
+
+     const test = (node: LGraphNode) => (node as any).isBackendNode
+     const nodeLocator = new UpstreamNodeLocator(test)
+     const [_, foundLink, foundInputSlot, foundPrevNode] = nodeLocator.locateUpstream(node, inputIndex, tag);
+
+     if (foundInputSlot != null && foundPrevNode != null) {
+         app.lCanvas.jumpToNodeAndInput(foundPrevNode, foundInputSlot);
+     }
+ }
+
+ function jumpToError(error: ComfyGraphErrorLocation) {
+     app.lCanvas.jumpToError(error);
+ }
+
+ function getInputTypeName(type: ComfyNodeDefInputType) {
+     if (Array.isArray(type)) {
+         return `List (${type.length})`
+     }
+     return type;
+ }
+</script>
+
+<div class="error-list">
+    <div class="error-list-header">
+        <button class="error-list-close" on:click={closeList}>✕</button>
+    </div>
+    {#each Object.entries(errors.errorsByID) as [nodeID, nodeErrors]}
+        {@const first = nodeErrors[0]}
+        {@const parent = getParentNode(first)}
+        <div class="error-group">
+            <div class="error-node-details">
+                <span class="error-node-type">{first.comfyNodeType}</span>
+                {#if parent}
+                    <span class="error-node-parent">({parent.title})</span>
+                {/if}
+            </div>
+            <div class="error-entries">
+                {#each nodeErrors as error}
+                    {@const isExecutionError = error.errorType === "execution"}
+                    <div class="error-entry">
+                        <div>
+                            <div class="error-details">
+                                <button class="jump-to-error" class:execution-error={isExecutionError} on:click={() => jumpToError(error)}><span>⮎</span></button>
+                                <div class="error-details-wrapper">
+                                    <span class="error-message" class:execution-error={isExecutionError}>{error.message}</span>
+                                    {#if error.exceptionType}
+                                        <span>({error.exceptionType})</span>
+                                    {/if}
+                                    {#if error.exceptionMessage && !isExecutionError}
+                                        <div style:text-decoration="underline">{error.exceptionMessage}</div>
+                                    {/if}
+                                    {#if error.input}
+                                        <div class="error-input">
+                                            <span>Input: <b>{error.input.name}</b></span>
+                                            {#if error.input.config}
+                                                <span>({getInputTypeName(error.input.config[0])})</span>
+                                            {/if}
+                                        </div>
+                                        {#if canJumpToDisconnectedInput(error)}
+                                            <div style:display="flex" style:flex-direction="row">
+                                                <button class="jump-to-error locate" on:click={() => jumpToDisconnectedInput(error)}><span>⮎</span></button>
+                                                <span>Find disconnected input</span>
+                                            </div>
+                                        {/if}
+
+                                        {#if error.input.receivedValue}
+                                            <div>
+                                                <span>Received value: <b>{error.input.receivedValue}</b></span>
+                                            </div>
+                                        {/if}
+                                        {#if error.input.receivedType}
+                                            <div>
+                                                <span>Received type: <b>{error.input.receivedType}</b></span>
+                                            </div>
+                                        {/if}
+                                        {#if error.input.config}
+                                            <div class="error-traceback-wrapper">
+                                                <Accordion label="Input Config" open={true}>
+                                                    <div class="error-traceback">
+                                                        <div class="error-traceback-contents">
+                                                            <JsonView json={error.input.config[1]} />
+                                                        </div>
+                                                    </div>
+                                                </Accordion>
+                                            </div>
+                                        {/if}
+                                    {/if}
+                                </div>
+                            </div>
+                        </div>
+                        {#if error.traceback}
+                            <div class="error-traceback-wrapper">
+                                <Accordion label="Traceback" open={false}>
+                                    <div class="error-traceback">
+                                        <div class="error-traceback-contents">
+                                            {#each error.traceback as line}
+                                                <pre>{line}</pre>
+                                            {/each}
+                                        </div>
+                                    </div>
+                                </Accordion>
+                            </div>
+                        {/if}
+                    </div>
+                {/each}
+            </div>
+        </div>
+    {/each}
+</div>
+
+<style lang="scss">
+
+ .error-list {
+     width: 30%;
+     height: 70%;
+     margin: 1.0rem;
+     overflow-y: auto;
+     position: absolute;
+     right: 0;
+     bottom: 0;
+     border: 1px solid #aaa;
+     color: #ddd;
+     background: #444;
+     font-size: 12pt;
+ }
+
+ .error-list-header {
+     width: 100%;
+     height: 24px;
+     margin: auto;
+     border-bottom: 1px solid #ccc;
+     background: #282828;
+     justify-content: center;
+     text-align: center;
+
+     .error-list-close {
+         margin: auto;
+         padding-right: 6px;
+         position: absolute;
+         top: 0;
+         right: 0;
+     }
+ }
+
+ .error-node-details {
+     font-size: 14pt;
+     color: #ddd;
+     font-weight: bold;
+     padding: 0.7rem 1.0rem;
+     background: #333;
+ }
+
+ .error-node-parent {
+     color: #aaa;
+     font-size: 12pt;
+     font-weight: initial;
+ }
+
+ .error-entries:last-child {
+     border-bottom: 1px solid #ccc;
+ }
+
+ .error-entry {
+     opacity: 100%;
+     border-top: 1px solid #ccc;
+     padding: 1rem;
+ }
+
+ .error-details {
+     width: 100%;
+     display: flex;
+     flex-direction: row;
+     gap: var(--spacing-md);
+     vertical-align: bottom;
+     position: relative;
+
+     > span {
+         bottom: 0;
+         display: flex;
+         flex-direction: column;
+         justify-content: center;
+     }
+ }
+
+ .error-details-wrapper {
+     flex: 5 1 0%;
+ }
+
+ .error-message {
+     color: #F66;
+     &.execution-error {
+         color: #E6E;
+     }
+     text-decoration: underline;
+ }
+
+ .error-input {
+     font-size: 12pt;
+ }
+
+ .jump-to-error {
+     border: 1px solid #ccc;
+     background: #844;
+     &.execution-error {
+         background: #848;
+     }
+     &.locate {
+         background: #488;
+     }
+     width: 32px;
+     height: 32px;
+     font-size: 14pt;
+     text-align: center;
+     display: flex;
+     position: relative;
+     justify-content: center;
+     margin-right: 0.3rem;
+
+     > span {
+         margin: auto;
+     }
+
+     &:hover {
+         filter: brightness(120%);
+     }
+
+     &:active {
+         filter: brightness(80%);
+     }
+ }
+
+ .error-traceback-wrapper {
+     width: 100%;
+     margin-top: 1.0rem;
+     padding: 0.5rem;
+     border: 1px solid #888;
+
+     .error-traceback {
+         font-size: 10pt;
+         overflow: auto;
+         white-space: nowrap;
+         background: #333;
+
+         .error-traceback-contents {
+             width: 100%;
+             font-family: monospace !important;
+             padding: 1.0rem;
+
+             > div {
+                 width: 100%;
+             }
+         }
+     }
+ }
+</style>
diff --git a/src/lib/components/ComfyGraphView.svelte b/src/lib/components/ComfyGraphView.svelte
index 44b35ac..6dea59b 100644
--- a/src/lib/components/ComfyGraphView.svelte
+++ b/src/lib/components/ComfyGraphView.svelte
@@ -1,28 +1,48 @@
 <script lang="ts">
- import { Button } from "@gradio/button";
+ import { onMount } from "svelte";
  import type ComfyApp from "./ComfyApp";
  import DropZone from "./DropZone.svelte";
  import interfaceState from "$lib/stores/interfaceState";
+ import workflowState from "$lib/stores/workflowState";
+ import uiState from '$lib/stores/uiState';
+ import ComfyGraphErrorList from "$lib/components/ComfyGraphErrorList.svelte"
 
  export let app: ComfyApp;
 
+ let canvas: HTMLCanvasElement;
+
+ onMount(async () => {
+     if (app?.lCanvas) {
+         canvas = app.lCanvas.canvas;
+         app.lCanvas?.setCanvas(canvas)
+     }
+ })
+
  function doRecenter(): void {
      app?.lCanvas?.recenter();
  }
+
+ function clearErrors(): void {
+     $uiState.activeError = null;
+ }
 </script>
 
 <div class="wrapper litegraph">
     <div class="canvas-wrapper pane-wrapper">
-        <canvas id="graph-canvas" />
+        <canvas bind:this={canvas} id="graph-canvas" />
         <DropZone {app} />
     </div>
     <div class="bar">
-        {#if !$interfaceState.graphTransitioning}
-            <span class="left">
-                <button on:click={doRecenter}>Recenter</button>
-            </span>
-        {/if}
+        <span class="left">
+            <button disabled={$interfaceState.graphTransitioning} on:click={doRecenter}>Recenter</button>
+            {#if $uiState.activeError != null}
+                <button disabled={$interfaceState.graphTransitioning} on:click={clearErrors}>Clear Errors</button>
+            {/if}
+        </span>
     </div>
+    {#if $uiState.activeError && app?.lCanvas?.activeErrors != null}
+        <ComfyGraphErrorList {app} errors={app.lCanvas.activeErrors} />
+    {/if}
 </div>
 
 <style lang="scss">
@@ -73,6 +93,9 @@
              background-color: #555;
              border-color: #777;
          }
+         &:disabled {
+             opacity: 50%;
+         }
      }
  }
 </style>
diff --git a/src/lib/components/ComfyPromptSerializer.ts b/src/lib/components/ComfyPromptSerializer.ts
index 1e1a540..51808d4 100644
--- a/src/lib/components/ComfyPromptSerializer.ts
+++ b/src/lib/components/ComfyPromptSerializer.ts
@@ -71,11 +71,13 @@ export function isActiveBackendNode(node: LGraphNode, tag: string | null = null)
     return true;
 }
 
+type UpstreamResult = [LGraph | null, LLink | null, number | null, LGraphNode | null];
+
 export class UpstreamNodeLocator {
     constructor(private isTheTargetNode: (node: LGraphNode) => boolean) {
     }
 
-    private followSubgraph(subgraph: Subgraph, link: LLink): [LGraph | null, LLink | null] {
+    private followSubgraph(subgraph: Subgraph, link: LLink): UpstreamResult {
         if (link.origin_id != subgraph.id)
             throw new Error("Invalid link and graph output!")
 
@@ -84,10 +86,10 @@ export class UpstreamNodeLocator {
             throw new Error("No inner graph input!")
 
         const nextLink = innerGraphOutput.getInputLink(0)
-        return [innerGraphOutput.graph, nextLink];
+        return [innerGraphOutput.graph, nextLink, 0, innerGraphOutput];
     }
 
-    private followGraphInput(graphInput: GraphInput, link: LLink): [LGraph | null, LLink | null] {
+    private followGraphInput(graphInput: GraphInput, link: LLink): UpstreamResult {
         if (link.origin_id != graphInput.id)
             throw new Error("Invalid link and graph input!")
 
@@ -100,10 +102,10 @@ export class UpstreamNodeLocator {
             throw new Error("No outer input slot!")
 
         const nextLink = outerSubgraph.getInputLink(outerInputIndex)
-        return [outerSubgraph.graph, nextLink];
+        return [outerSubgraph.graph, nextLink, outerInputIndex, outerSubgraph];
     }
 
-    private getUpstreamLink(parent: LGraphNode, currentLink: LLink): [LGraph | null, LLink | null] {
+    private getUpstreamLink(parent: LGraphNode, currentLink: LLink): UpstreamResult {
         if (parent.is(Subgraph)) {
             console.debug("FollowSubgraph")
             return this.followSubgraph(parent, currentLink);
@@ -113,17 +115,18 @@ export class UpstreamNodeLocator {
             return this.followGraphInput(parent, currentLink);
         }
         else if ("getUpstreamLink" in parent) {
-            return [parent.graph, (parent as ComfyGraphNode).getUpstreamLink()];
+            const link = (parent as ComfyGraphNode).getUpstreamLink();
+            return [parent.graph, link, link?.target_slot, parent];
         }
         else if (parent.inputs.length === 1) {
             // Only one input, so assume we can follow it backwards.
             const link = parent.getInputLink(0);
             if (link) {
-                return [parent.graph, link]
+                return [parent.graph, link, 0, parent]
             }
         }
         console.warn("[graphToPrompt] Frontend node does not support getUpstreamLink", parent.type)
-        return [null, null];
+        return [null, null, null, null];
     }
 
     /*
@@ -133,13 +136,15 @@ export class UpstreamNodeLocator {
      * Returns the node and the output link attached to it that leads to the
      * starting node if any.
      */
-    locateUpstream(fromNode: LGraphNode, inputIndex: SlotIndex, tag: string | null): [LGraphNode | null, LLink | null] {
+    locateUpstream(fromNode: LGraphNode, inputIndex: SlotIndex, tag: string | null): [LGraphNode | null, LLink | null, number | null, LGraphNode | null] {
         let parent = fromNode.getInputNode(inputIndex);
         if (!parent)
-            return [null, null];
+            return [null, null, null, null];
 
         const seen = {}
         let currentLink = fromNode.getInputLink(inputIndex);
+        let currentInputSlot = inputIndex;
+        let currentNode = fromNode;
 
         const shouldFollowParent = (parent: LGraphNode) => {
             return isActiveNode(parent, tag) && !this.isTheTargetNode(parent);
@@ -152,7 +157,10 @@ export class UpstreamNodeLocator {
         // nodes have conditional logic that determines which link
         // to follow backwards.
         while (shouldFollowParent(parent)) {
-            const [nextGraph, nextLink] = this.getUpstreamLink(parent, currentLink);
+            const [nextGraph, nextLink, nextInputSlot, nextNode] = this.getUpstreamLink(parent, currentLink);
+
+            currentInputSlot = nextInputSlot;
+            currentNode = nextNode;
 
             if (nextLink == null) {
                 console.warn("[graphToPrompt] No upstream link found in frontend node", parent)
@@ -176,9 +184,9 @@ export class UpstreamNodeLocator {
         }
 
         if (!isActiveNode(parent, tag) || !this.isTheTargetNode(parent) || currentLink == null)
-            return [null, null];
+            return [null, currentLink, currentInputSlot, currentNode];
 
-        return [parent, currentLink]
+        return [parent, currentLink, currentInputSlot, currentNode]
     }
 }
 
diff --git a/src/lib/components/ComfyQueue.svelte b/src/lib/components/ComfyQueue.svelte
index 3b66d04..9d8bd75 100644
--- a/src/lib/components/ComfyQueue.svelte
+++ b/src/lib/components/ComfyQueue.svelte
@@ -8,7 +8,8 @@
      date?: string,
      status: QueueUIEntryStatus,
      images?: string[], // URLs
-     details?: string // shown in a tooltip on hover
+     details?: string, // shown in a tooltip on hover
+     error?: WorkflowError
  }
 </script>
 
@@ -21,15 +22,14 @@
  import { convertComfyOutputToComfyURL, convertFilenameToComfyURL, getNodeInfo, truncateString } from "$lib/utils"
  import type { Writable } from "svelte/store";
  import type { QueueItemType } from "$lib/api";
- import { ImageViewer } from "$lib/ImageViewer";
  import { Button } from "@gradio/button";
  import type ComfyApp from "./ComfyApp";
- import { tick } from "svelte";
+ import { getContext, tick } from "svelte";
  import Modal from "./Modal.svelte";
- import DropZone from "./DropZone.svelte";
-	import workflowState from "$lib/stores/workflowState";
+ import { type WorkflowError } from "$lib/stores/workflowState";
  import ComfyQueueListDisplay from "./ComfyQueueListDisplay.svelte";
  import ComfyQueueGridDisplay from "./ComfyQueueGridDisplay.svelte";
+	import { WORKFLOWS_VIEW } from "./ComfyBoxWorkflowsView.svelte";
 
  export let app: ComfyApp;
 
@@ -38,6 +38,8 @@
  let queueCompleted: Writable<CompletedQueueEntry[]> | null = null;
  let queueList: HTMLDivElement | null = null;
 
+ const { showError } = getContext(WORKFLOWS_VIEW) as any;
+
  $: if ($queueState) {
      queuePending = $queueState.queuePending
      queueRunning = $queueState.queueRunning
@@ -144,9 +146,11 @@
      if (entry.extraData?.workflowTitle != null) {
          message = `${entry.extraData.workflowTitle}`
      }
-     const subgraphsString = subgraphs.join(', ')
-     if (subgraphsString.length > 0)
-         message += ` (${subgraphsString})`
+     if (subgraphs) {
+         const subgraphsString = subgraphs.join(', ')
+         if (subgraphsString.length > 0)
+             message += ` (${subgraphsString})`
+     }
 
      let submessage = `Nodes: ${Object.keys(entry.prompt).length}`
 
@@ -198,7 +202,7 @@
      else if (entry.status === "interrupted" || entry.status === "all_cached")
          result.submessage = "Prompt was interrupted."
      if (entry.error)
-         result.details = entry.error
+         result.error = entry.error
 
      return result;
  }
@@ -232,10 +236,20 @@
  let selectedPrompt = null;
  let selectedImages = [];
  function showPrompt(entry: QueueUIEntry) {
-     selectedPrompt = entry.entry.prompt;
-     selectedImages = entry.images;
-     showModal = true;
-     expandAll = false
+     if (entry.error != null) {
+         showModal = false;
+         expandAll = false;
+         selectedPrompt = null;
+         selectedImages = [];
+
+         showError(entry.entry.promptID);
+     }
+     else {
+         selectedPrompt = entry.entry.prompt;
+         selectedImages = entry.images;
+         showModal = true;
+         expandAll = false
+     }
  }
 
  function closeModal() {
diff --git a/src/lib/components/ComfyQueueListDisplay.svelte b/src/lib/components/ComfyQueueListDisplay.svelte
index 09caf2e..751a9f8 100644
--- a/src/lib/components/ComfyQueueListDisplay.svelte
+++ b/src/lib/components/ComfyQueueListDisplay.svelte
@@ -148,8 +148,11 @@
      &.success {
          /* background: green; */
      }
+     &.validation_failed {
+         background: #551a1a;
+     }
      &.error {
-         background: red;
+         background: #401a40;
      }
      &.all_cached, &.interrupted {
          filter: brightness(80%);
diff --git a/src/lib/components/OnClickToastItem.svelte b/src/lib/components/OnClickToastItem.svelte
new file mode 100644
index 0000000..b1d8a11
--- /dev/null
+++ b/src/lib/components/OnClickToastItem.svelte
@@ -0,0 +1,18 @@
+<script lang="ts">
+ import type { NotifyOptions } from "$lib/notify";
+ import { toast } from "@zerodevx/svelte-toast";
+
+ export let message: string = ""
+ export let notifyOptions: NotifyOptions
+ export let toastID: string
+
+ function onClick() {
+     if (notifyOptions.onClick) {
+         notifyOptions.onClick()
+         toast.pop(toastID)
+     }
+ }
+</script>
+
+<!-- svelte-ignore a11y-click-events-have-key-events -->
+<div on:click={onClick}>{message}</div>
diff --git a/src/lib/components/gradio/image/StaticImage.svelte b/src/lib/components/gradio/image/StaticImage.svelte
index eda153d..a060161 100644
--- a/src/lib/components/gradio/image/StaticImage.svelte
+++ b/src/lib/components/gradio/image/StaticImage.svelte
@@ -2,7 +2,7 @@
 	import { createEventDispatcher } from "svelte";
 	import type { SelectData } from "@gradio/utils";
 	import { BlockLabel, Empty, IconButton } from "@gradio/atoms";
-	import { Download } from "@gradio/icons";
+	import { Download, Clear } from "@gradio/icons";
 	import { get_coordinates_of_clicked_image } from "./utils";
 
 	import { Image } from "@gradio/icons";
@@ -33,13 +33,17 @@
 			dispatch("select", { index: coordinates, value: null });
 		}
 	};
+
+ function remove() {
+     value = null;
+ }
 </script>
 
 <BlockLabel {show_label} Icon={Image} label={label || "Image"} />
 {#if value === null}
 	<Empty size="large" unpadded_box={true}><Image /></Empty>
 {:else}
-	<div class="download">
+	<div class="buttons">
 		<a
 			href={value}
 			target={window.__is_colab__ ? "_blank" : null}
@@ -47,6 +51,7 @@
 		>
 			<IconButton Icon={Download} label="Download" />
 		</a>
+        <IconButton Icon={Clear} label="Remove" on:click={remove} />
 	</div>
 	<!-- svelte-ignore a11y-click-events-have-key-events -->
 	<img src={value} alt="" class:selectable on:click={handle_click} bind:naturalWidth={imageWidth} bind:naturalHeight={imageHeight} />
@@ -63,9 +68,13 @@
 		cursor: crosshair;
 	}
 
-	.download {
+	.buttons {
+		display: flex;
 		position: absolute;
-		top: 6px;
-		right: 6px;
+		top: var(--size-2);
+		right: var(--size-2);
+		justify-content: flex-end;
+		gap: var(--spacing-sm);
+		z-index: var(--layer-5);
 	}
 </style>
diff --git a/src/lib/nodes/widgets/ComfyGalleryNode.ts b/src/lib/nodes/widgets/ComfyGalleryNode.ts
index afbe8ff..1267d18 100644
--- a/src/lib/nodes/widgets/ComfyGalleryNode.ts
+++ b/src/lib/nodes/widgets/ComfyGalleryNode.ts
@@ -99,6 +99,12 @@ export default class ComfyGalleryNode extends ComfyWidgetNode<ComfyBoxImageMetad
         if (newIndex != null) {
             this.selectedImage.set(newIndex)
             this.forceSelectImage.set(true)
+
+            const image = this.getValue()[newIndex]
+            if (image) {
+                this.imageWidth.set(image.width || 0)
+                this.imageHeight.set(image.height || 0)
+            }
         }
     }
 
diff --git a/src/lib/notify.ts b/src/lib/notify.ts
index 167980d..3de3405 100644
--- a/src/lib/notify.ts
+++ b/src/lib/notify.ts
@@ -2,13 +2,16 @@ import { toast } from "@zerodevx/svelte-toast";
 import type { SvelteToastOptions } from "@zerodevx/svelte-toast/stores";
 import { type Notification } from "framework7/components/notification"
 import { f7 } from "framework7-svelte"
+import OnClickToastItem from "$lib/components/OnClickToastItem.svelte"
 
 export type NotifyOptions = {
     title?: string,
     type?: "neutral" | "info" | "warning" | "error" | "success",
     imageUrl?: string,
     timeout?: number | null,
-    showOn?: "web" | "native" | "all" | "none"
+    showOn?: "web" | "native" | "all" | "none",
+    showBar?: boolean,
+    onClick?: () => void,
 }
 
 function notifyf7(text: string, options: NotifyOptions) {
@@ -19,13 +22,19 @@ function notifyf7(text: string, options: NotifyOptions) {
     if (closeTimeout === undefined)
         closeTimeout = 3000;
 
+    const on: Notification.Parameters["on"] = {}
+    if (options.onClick) {
+        on.click = () => options.onClick();
+    }
+
     const notification = f7.notification.create({
         title: options.title,
         titleRightText: 'now',
         // subtitle: 'Notification with close on click',
         text: text,
         closeOnClick: true,
-        closeTimeout
+        closeTimeout,
+        on
     });
     notification.open();
 }
@@ -33,30 +42,47 @@ function notifyf7(text: string, options: NotifyOptions) {
 function notifyToast(text: string, options: NotifyOptions) {
     const toastOptions: SvelteToastOptions = {
         dismissable: options.timeout !== null,
+        duration: options.timeout || 5000,
+        theme: {},
+    }
+
+    if (options.showBar) {
+        toastOptions.theme['--toastBarHeight'] = "6px"
     }
 
     if (options.type === "success") {
-        toastOptions.theme = {
-            '--toastBackground': 'var(--color-green-600)',
-        }
+        toastOptions.theme['--toastBackground'] = 'var(--color-green-600)';
+        toastOptions.theme['--toastBarBackground'] = 'var(--color-green-900)';
     }
     else if (options.type === "info") {
-        toastOptions.theme = {
-            '--toastBackground': 'var(--color-blue-500)',
-        }
+        toastOptions.theme['--toastBackground'] = 'var(--color-blue-500)';
+        toastOptions.theme['--toastBarBackground'] = 'var(--color-blue-800)';
     }
     else if (options.type === "warning") {
-        toastOptions.theme = {
-            '--toastBackground': 'var(--color-yellow-600)',
-        }
+        toastOptions.theme['--toastBackground'] = 'var(--color-yellow-600)';
+        toastOptions.theme['--toastBarBackground'] = 'var(--color-yellow-900)';
     }
     else if (options.type === "error") {
-        toastOptions.theme = {
-            '--toastBackground': 'var(--color-red-500)',
-        }
+        toastOptions.theme['--toastBackground'] = 'var(--color-red-500)';
+        toastOptions.theme['--toastBarBackground'] = 'var(--color-red-800)';
     }
 
-    toast.push(text, toastOptions);
+    if (options.onClick) {
+        toast.push({
+            component: {
+                src: OnClickToastItem,
+                props: {
+                    message: text,
+                    notifyOptions: options
+                },
+                sendIdTo: "toastID"
+            },
+            ...toastOptions
+        })
+    }
+    else {
+        toast.push(text, toastOptions);
+    }
 }
 
 function notifyNative(text: string, options: NotifyOptions) {
@@ -78,7 +104,11 @@ function notifyNative(text: string, options: NotifyOptions) {
 
     const notification = new Notification(title, nativeOptions);
 
-    notification.onclick = () => window.focus();
+    notification.onclick = () => {
+        window.focus();
+        if (options.onClick)
+            options.onClick();
+    }
 }
 
 export default function notify(text: string, options: NotifyOptions = {}) {
diff --git a/src/lib/stores/queueState.ts b/src/lib/stores/queueState.ts
index 996377f..82712d9 100644
--- a/src/lib/stores/queueState.ts
+++ b/src/lib/stores/queueState.ts
@@ -1,12 +1,14 @@
-import type { ComfyAPIHistoryEntry, ComfyAPIHistoryItem, ComfyAPIHistoryResponse, ComfyAPIQueueResponse, ComfyAPIStatusResponse, ComfyBoxPromptExtraData, ComfyNodeID, PromptID, QueueItemType } from "$lib/api";
-import type { Progress, SerializedPromptInputsAll, SerializedPromptOutputs, WorkflowInstID } from "$lib/components/ComfyApp";
+import type { ComfyAPIHistoryEntry, ComfyAPIHistoryItem, ComfyAPIHistoryResponse, ComfyAPIQueueResponse, ComfyAPIStatusResponse, ComfyBoxPromptExtraData, ComfyExecutionError, ComfyNodeID, PromptID, QueueItemType } from "$lib/api";
+import type { ComfyAPIPromptErrorResponse } from "$lib/apiErrors";
+import type { Progress, SerializedPrompt, SerializedPromptInputsAll, SerializedPromptOutputs, } from "$lib/components/ComfyApp";
 import type { ComfyExecutionResult } from "$lib/nodes/ComfyWidgetNodes";
 import notify from "$lib/notify";
-import { get, writable, type Writable } from "svelte/store";
-import workflowState from "./workflowState";
 import { playSound } from "$lib/utils";
+import { get, writable, type Writable } from "svelte/store";
+import { v4 as uuidv4 } from "uuid";
+import workflowState, { type WorkflowError, type WorkflowExecutionError, type WorkflowInstID, type WorkflowValidationError } from "./workflowState";
 
-export type QueueEntryStatus = "success" | "error" | "interrupted" | "all_cached" | "unknown";
+export type QueueEntryStatus = "success" | "validation_failed" | "error" | "interrupted" | "all_cached" | "unknown";
 
 type QueueStateOps = {
     queueUpdated: (resp: ComfyAPIQueueResponse) => void,
@@ -15,13 +17,14 @@ type QueueStateOps = {
     executionStart: (promptID: PromptID) => void,
     executingUpdated: (promptID: PromptID | null, runningNodeID: ComfyNodeID | null) => QueueEntry | null;
     executionCached: (promptID: PromptID, nodes: ComfyNodeID[]) => void,
-    executionError: (promptID: PromptID, message: string) => void,
+    executionError: (error: ComfyExecutionError) => CompletedQueueEntry | null,
     progressUpdated: (progress: Progress) => void
     getQueueEntry: (promptID: PromptID) => QueueEntry | null;
     afterQueued: (workflowID: WorkflowInstID, promptID: PromptID, number: number, prompt: SerializedPromptInputsAll, extraData: any) => void
     queueItemDeleted: (type: QueueItemType, id: PromptID) => void;
     queueCleared: (type: QueueItemType) => void;
     onExecuted: (promptID: PromptID, nodeID: ComfyNodeID, output: ComfyExecutionResult) => QueueEntry | null
+    promptError: (id: WorkflowInstID, error: ComfyAPIPromptErrorResponse, prompt: SerializedPrompt, extraData: ComfyBoxPromptExtraData) => PromptID
 }
 
 /*
@@ -34,6 +37,10 @@ export type QueueEntry = {
     number: number,
     queuedAt?: Date,
     finishedAt?: Date,
+    /*
+     * Can also be generated by the frontend if prompt validation fails
+     * (the backend won't send back a prompt ID in that case)
+     */
     promptID: PromptID,
     prompt: SerializedPromptInputsAll,
     extraData: ComfyBoxPromptExtraData,
@@ -46,7 +53,7 @@ export type QueueEntry = {
     /* Nodes of the workflow that have finished running so far. */
     nodesRan: Set<ComfyNodeID>,
     /* Nodes of the workflow the backend reported as cached. */
-    cachedNodes: Set<ComfyNodeID>
+    cachedNodes: Set<ComfyNodeID>,
 }
 
 /*
@@ -61,7 +68,7 @@ export type CompletedQueueEntry = {
     /** Message to display in the frontend */
     message?: string,
     /** Detailed error/stacktrace, perhaps inspectible with a popup */
-    error?: string,
+    error?: WorkflowError
 }
 
 /*
@@ -229,21 +236,32 @@ function moveToRunning(index: number, queue: Writable<QueueEntry[]>) {
     store.set(state)
 }
 
-function moveToCompleted(index: number, queue: Writable<QueueEntry[]>, status: QueueEntryStatus, message?: string, error?: string) {
+function moveToCompleted(index: number, queue: Writable<QueueEntry[]>, status: QueueEntryStatus, message?: string, error?: ComfyExecutionError): CompletedQueueEntry {
     const state = get(store)
-
     const entry = get(queue)[index];
+
+    let workflowError: WorkflowExecutionError | null = null;
+    if (error) {
+        workflowError = {
+            type: "execution",
+            error
+        }
+        entry.nodesRan = new Set(error.executed);
+    }
+
     console.debug("[queueState] Move to completed", entry.promptID, index, status, message, error)
     entry.finishedAt = new Date() // Now
     queue.update(qp => { qp.splice(index, 1); return qp });
+    const completed: CompletedQueueEntry = { entry, status, message, error: workflowError }
     state.queueCompleted.update(qc => {
-        const completed: CompletedQueueEntry = { entry, status, message, error }
         qc.push(completed)
         return qc
     })
 
     state.isInterrupting = false;
     store.set(state)
+
+    return completed;
 }
 
 function executingUpdated(promptID: PromptID, runningNodeID: ComfyNodeID | null): QueueEntry | null {
@@ -314,20 +332,22 @@ function executionCached(promptID: PromptID, nodes: ComfyNodeID[]) {
     })
 }
 
-function executionError(promptID: PromptID, message: string) {
-    console.debug("[queueState] executionError", promptID, message)
+function executionError(error: ComfyExecutionError): CompletedQueueEntry | null {
+    console.debug("[queueState] executionError", error)
+    let entry_ = null;
     store.update(s => {
-        const [index, entry, queue] = findEntryInPending(promptID);
+        const [index, entry, queue] = findEntryInPending(error.prompt_id);
         if (entry != null) {
-            moveToCompleted(index, queue, "error", "Error executing", message)
+            entry_ = moveToCompleted(index, queue, "error", "Error executing", error)
         }
         else {
-            console.error("[queueState] Could not find in pending! (executionError)", promptID)
+            console.error("[queueState] Could not find in pending! (executionError)", error.prompt_id)
         }
         s.progress = null;
         s.runningNodeID = null;
         return s
     })
+    return entry_;
 }
 
 function createNewQueueEntry(promptID: PromptID, number: number = -1, prompt: SerializedPromptInputsAll = {}, extraData: any = {}): QueueEntry {
@@ -432,6 +452,43 @@ function queueCleared(type: QueueItemType) {
     })
 }
 
+function promptError(workflowID: WorkflowInstID, error: ComfyAPIPromptErrorResponse, prompt: SerializedPrompt, extraData: ComfyBoxPromptExtraData): PromptID {
+    const workflowError: WorkflowValidationError = {
+        type: "validation",
+        workflowID,
+        error,
+        prompt,
+        extraData
+    }
+
+    const entry: QueueEntry = {
+        number: 0,
+        queuedAt: new Date(), // Now
+        finishedAt: new Date(),
+        promptID: uuidv4(), // Just for keeping track
+        prompt: prompt.output,
+        extraData,
+        goodOutputs: [],
+        outputs: {},
+        nodesRan: new Set(),
+        cachedNodes: new Set(),
+    }
+
+    const completedEntry: CompletedQueueEntry = {
+        entry,
+        status: "validation_failed",
+        message: "Validation failed",
+        error: workflowError
+    }
+
+    store.update(s => {
+        s.queueCompleted.update(qc => { qc.push(completedEntry); return qc })
+        return s;
+    })
+
+    return entry.promptID;
+}
+
 const queueStateStore: WritableQueueStateStore =
 {
     ...store,
@@ -447,6 +504,7 @@ const queueStateStore: WritableQueueStateStore =
     queueItemDeleted,
     queueCleared,
     getQueueEntry,
-    onExecuted
+    onExecuted,
+    promptError,
 }
 export default queueStateStore;
diff --git a/src/lib/stores/uiState.ts b/src/lib/stores/uiState.ts
index 39076ed..e28bc90 100644
--- a/src/lib/stores/uiState.ts
+++ b/src/lib/stores/uiState.ts
@@ -1,3 +1,4 @@
+import type { PromptID } from '$lib/api';
 import { writable } from 'svelte/store';
 import type { Readable, Writable } from 'svelte/store';
 
@@ -11,7 +12,9 @@ export type UIState = {
     uiEditMode: UIEditMode,
 
     reconnecting: boolean,
-    forceSaveUserState: boolean | null
+    forceSaveUserState: boolean | null,
+
+    activeError: PromptID | null
 }
 
 type UIStateOps = {
@@ -30,6 +33,8 @@ const store: Writable<UIState> = writable(
 
         reconnecting: false,
         forceSaveUserState: null,
+
+        activeError: null
     })
 
 function reconnecting() {
diff --git a/src/lib/stores/workflowState.ts b/src/lib/stores/workflowState.ts
index d795c17..55ba772 100644
--- a/src/lib/stores/workflowState.ts
+++ b/src/lib/stores/workflowState.ts
@@ -8,8 +8,10 @@ import layoutStates from './layoutStates';
 import { v4 as uuidv4 } from "uuid";
 import type ComfyGraphCanvas from '$lib/ComfyGraphCanvas';
 import { blankGraph } from '$lib/defaultGraph';
-import type { SerializedAppState } from '$lib/components/ComfyApp';
+import type { SerializedAppState, SerializedPrompt } from '$lib/components/ComfyApp';
 import type ComfyReceiveOutputNode from '$lib/nodes/actions/ComfyReceiveOutputNode';
+import type { ComfyBoxPromptExtraData, PromptID } from '$lib/api';
+import type { ComfyAPIPromptErrorResponse, ComfyExecutionError } from '$lib/apiErrors';
 
 type ActiveCanvas = {
     canvas: LGraphCanvas | null;
@@ -63,6 +65,21 @@ export type WorkflowAttributes = {
     showDefaultNotifications: boolean,
 }
 
+export type WorkflowValidationError = {
+    type: "validation"
+    workflowID: WorkflowInstID,
+    error: ComfyAPIPromptErrorResponse,
+    prompt: SerializedPrompt,
+    extraData: ComfyBoxPromptExtraData
+}
+
+export type WorkflowExecutionError = {
+    type: "execution"
+    error: ComfyExecutionError,
+}
+
+export type WorkflowError = WorkflowValidationError | WorkflowExecutionError;
+
 export class ComfyBoxWorkflow {
     /*
      * Used for uniquely identifying the instance of the opened workflow in the frontend.
@@ -89,6 +106,11 @@ export class ComfyBoxWorkflow {
      */
     missingNodeTypes: Set<string> = new Set();
 
+    /*
+     * Completed queue entry ID that holds the last validation/execution error.
+     */
+    lastError?: PromptID
+
     get layout(): WritableLayoutStateStore | null {
         return layoutStates.getLayout(this.id)
     }
@@ -257,7 +279,10 @@ type WorkflowStateOps = {
     closeWorkflow: (canvas: ComfyGraphCanvas, index: number) => void,
     closeAllWorkflows: (canvas: ComfyGraphCanvas) => void,
     setActiveWorkflow: (canvas: ComfyGraphCanvas, index: number | WorkflowInstID) => ComfyBoxWorkflow | null,
-    findReceiveOutputTargets: (type: SlotType | SlotType[]) => WorkflowReceiveOutputTargets[]
+    findReceiveOutputTargets: (type: SlotType | SlotType[]) => WorkflowReceiveOutputTargets[],
+    afterQueued: (id: WorkflowInstID, promptID: PromptID) => void
+    promptError: (id: WorkflowInstID, promptID: PromptID) => void
+    executionError: (id: WorkflowInstID, promptID: PromptID) => void
 }
 
 export type WritableWorkflowStateStore = Writable<WorkflowState> & WorkflowStateOps;
@@ -420,6 +445,36 @@ function findReceiveOutputTargets(type: SlotType | SlotType[]): WorkflowReceiveO
     return result;
 }
 
+function afterQueued(id: WorkflowInstID, promptID: PromptID) {
+    const workflow = getWorkflow(id);
+    if (workflow == null) {
+        console.warn("[workflowState] afterQueued: workflow not found", id, promptID)
+        return
+    }
+
+    workflow.lastError = null;
+}
+
+function promptError(id: WorkflowInstID, promptID: PromptID) {
+    const workflow = getWorkflow(id);
+    if (workflow == null) {
+        console.warn("[workflowState] promptError: workflow not found", id, promptID)
+        return
+    }
+
+    workflow.lastError = promptID;
+}
+
+function executionError(id: WorkflowInstID, promptID: PromptID) {
+    const workflow = getWorkflow(id);
+    if (workflow == null) {
+        console.warn("[workflowState] executionError: workflow not found", id, promptID)
+        return
+    }
+
+    workflow.lastError = promptID;
+}
+
 const workflowStateStore: WritableWorkflowStateStore =
 {
     ...store,
@@ -434,6 +489,9 @@ const workflowStateStore: WritableWorkflowStateStore =
     closeWorkflow,
     closeAllWorkflows,
     setActiveWorkflow,
-    findReceiveOutputTargets
+    findReceiveOutputTargets,
+    afterQueued,
+    promptError,
+    executionError,
 }
 export default workflowStateStore;
diff --git a/src/lib/widgets/ImageUploadWidget.svelte b/src/lib/widgets/ImageUploadWidget.svelte
index 09f6fa6..a16f96b 100644
--- a/src/lib/widgets/ImageUploadWidget.svelte
+++ b/src/lib/widgets/ImageUploadWidget.svelte
@@ -6,7 +6,7 @@
  import { get, writable, type Writable } from "svelte/store";
  import Modal from "$lib/components/Modal.svelte";
  import { Button } from "@gradio/button";
- import { Embed as Klecks } from "klecks";
+ import { type Embed as Klecks } from "klecks";
 
  import "klecks/style/style.scss";
  import ImageUpload from "$lib/components/ImageUpload.svelte";
@@ -97,6 +97,8 @@
  let blankImageWidth = 512;
  let blankImageHeight = 512;
 
+ let klecks: typeof import("klecks") | null = null;
+
  async function openImageEditor() {
      if (!editorRoot)
          return;
@@ -105,7 +107,9 @@
 
      const url = configState.getBackendURL();
 
-     kl = new Klecks({
+     klecks ||= await import("klecks");
+
+     kl = new klecks.Embed({
          embedUrl: url,
          onSubmit: submitKlecksToComfyUI,
          targetEl: editorRoot,