WebUI Architecture Cleanup (#19541)

* webui: architecture foundation (non-MCP core refactors)

* chore: update webui build output

tools/server/webui/src/lib/constants/binary-detection.ts

@@ -1,9 +1,6 @@
 export interface BinaryDetectionOptions {
-	/** Number of characters to check from the beginning of the file */
 	prefixLength: number;
-	/** Maximum ratio of suspicious characters allowed (0.0 to 1.0) */
 	suspiciousCharThresholdRatio: number;
-	/** Maximum absolute number of null bytes allowed */
 	maxAbsoluteNullBytes: number;
 }
 

tools/server/webui/src/lib/constants/chat-form.ts

@@ -0,0 +1,3 @@
+export const INITIAL_FILE_SIZE = 0;
+export const PROMPT_CONTENT_SEPARATOR = '\n\n';
+export const CLIPBOARD_CONTENT_QUOTE_PREFIX = '"';

tools/server/webui/src/lib/constants/code-blocks.ts

@@ -0,0 +1,8 @@
+export const CODE_BLOCK_SCROLL_CONTAINER_CLASS = 'code-block-scroll-container';
+export const CODE_BLOCK_WRAPPER_CLASS = 'code-block-wrapper';
+export const CODE_BLOCK_HEADER_CLASS = 'code-block-header';
+export const CODE_BLOCK_ACTIONS_CLASS = 'code-block-actions';
+export const CODE_LANGUAGE_CLASS = 'code-language';
+export const COPY_CODE_BTN_CLASS = 'copy-code-btn';
+export const PREVIEW_CODE_BTN_CLASS = 'preview-code-btn';
+export const RELATIVE_CLASS = 'relative';

tools/server/webui/src/lib/constants/code.ts

@@ -0,0 +1,7 @@
+export const NEWLINE = '\n';
+export const DEFAULT_LANGUAGE = 'text';
+export const LANG_PATTERN = /^(\w*)\n?/;
+export const AMPERSAND_REGEX = /&/g;
+export const LT_REGEX = /</g;
+export const GT_REGEX = />/g;
+export const FENCE_PATTERN = /^```|\n```/g;

tools/server/webui/src/lib/constants/css-classes.ts

@@ -0,0 +1,10 @@
+export const BOX_BORDER =
+	'border border-border/30 focus-within:border-border  dark:border-border/20 dark:focus-within:border-border';
+
+export const INPUT_CLASSES = `
+    bg-muted/60 dark:bg-muted/75
+    ${BOX_BORDER}
+    shadow-sm
+    outline-none
+    text-foreground
+`;

tools/server/webui/src/lib/constants/formatters.ts

@@ -0,0 +1,8 @@
+export const MS_PER_SECOND = 1000;
+export const SECONDS_PER_MINUTE = 60;
+export const SECONDS_PER_HOUR = 3600;
+export const SHORT_DURATION_THRESHOLD = 1;
+export const MEDIUM_DURATION_THRESHOLD = 10;
+
+/** Default display value when no performance time is available */
+export const DEFAULT_PERFORMANCE_TIME = '0s';

tools/server/webui/src/lib/constants/markdown.ts

@@ -0,0 +1,4 @@
+export const IMAGE_NOT_ERROR_BOUND_SELECTOR = 'img:not([data-error-bound])';
+export const DATA_ERROR_BOUND_ATTR = 'errorBound';
+export const DATA_ERROR_HANDLED_ATTR = 'errorHandled';
+export const BOOL_TRUE_STRING = 'true';

tools/server/webui/src/lib/constants/processing-info.ts

@@ -1 +1,8 @@
 export const PROCESSING_INFO_TIMEOUT = 2000;
+
+/**
+ * Statistics units labels
+ */
+export const STATS_UNITS = {
+	TOKENS_PER_SECOND: 't/s'
+} as const;

tools/server/webui/src/lib/constants/settings-fields.ts

@@ -0,0 +1,33 @@
+/**
+ * List of all numeric fields in settings configuration.
+ * These fields will be converted from strings to numbers during save.
+ */
+export const NUMERIC_FIELDS = [
+	'temperature',
+	'top_k',
+	'top_p',
+	'min_p',
+	'max_tokens',
+	'pasteLongTextToFileLen',
+	'dynatemp_range',
+	'dynatemp_exponent',
+	'typ_p',
+	'xtc_probability',
+	'xtc_threshold',
+	'repeat_last_n',
+	'repeat_penalty',
+	'presence_penalty',
+	'frequency_penalty',
+	'dry_multiplier',
+	'dry_base',
+	'dry_allowed_length',
+	'dry_penalty_last_n',
+	'agenticMaxTurns',
+	'agenticMaxToolPreviewLines'
+] as const;
+
+/**
+ * Fields that must be positive integers (>= 1).
+ * These will be clamped to minimum 1 and rounded during save.
+ */
+export const POSITIVE_INTEGER_FIELDS = ['agenticMaxTurns', 'agenticMaxToolPreviewLines'] as const;

tools/server/webui/src/lib/constants/tooltip-config.ts

@@ -1 +1 @@
-export const TOOLTIP_DELAY_DURATION = 100;
+export const TOOLTIP_DELAY_DURATION = 500;

tools/server/webui/src/lib/constants/ui.ts

@@ -0,0 +1 @@
+export const SYSTEM_MESSAGE_PLACEHOLDER = 'System message';

tools/server/webui/src/lib/contexts/chat-actions.context.ts

@@ -0,0 +1,34 @@
+import { getContext, setContext } from 'svelte';
+
+export interface ChatActionsContext {
+	copy: (message: DatabaseMessage) => void;
+	delete: (message: DatabaseMessage) => void;
+	navigateToSibling: (siblingId: string) => void;
+	editWithBranching: (
+		message: DatabaseMessage,
+		newContent: string,
+		newExtras?: DatabaseMessageExtra[]
+	) => void;
+	editWithReplacement: (
+		message: DatabaseMessage,
+		newContent: string,
+		shouldBranch: boolean
+	) => void;
+	editUserMessagePreserveResponses: (
+		message: DatabaseMessage,
+		newContent: string,
+		newExtras?: DatabaseMessageExtra[]
+	) => void;
+	regenerateWithBranching: (message: DatabaseMessage, modelOverride?: string) => void;
+	continueAssistantMessage: (message: DatabaseMessage) => void;
+}
+
+const CHAT_ACTIONS_KEY = Symbol.for('chat-actions');
+
+export function setChatActionsContext(ctx: ChatActionsContext): ChatActionsContext {
+	return setContext(CHAT_ACTIONS_KEY, ctx);
+}
+
+export function getChatActionsContext(): ChatActionsContext {
+	return getContext(CHAT_ACTIONS_KEY);
+}

tools/server/webui/src/lib/contexts/index.ts

@@ -0,0 +1,13 @@
+export {
+	getMessageEditContext,
+	setMessageEditContext,
+	type MessageEditContext,
+	type MessageEditState,
+	type MessageEditActions
+} from './message-edit.context';
+
+export {
+	getChatActionsContext,
+	setChatActionsContext,
+	type ChatActionsContext
+} from './chat-actions.context';

tools/server/webui/src/lib/contexts/message-edit.context.ts

@@ -0,0 +1,39 @@
+import { getContext, setContext } from 'svelte';
+
+export interface MessageEditState {
+	readonly isEditing: boolean;
+	readonly editedContent: string;
+	readonly editedExtras: DatabaseMessageExtra[];
+	readonly editedUploadedFiles: ChatUploadedFile[];
+	readonly originalContent: string;
+	readonly originalExtras: DatabaseMessageExtra[];
+	readonly showSaveOnlyOption: boolean;
+}
+
+export interface MessageEditActions {
+	setContent: (content: string) => void;
+	setExtras: (extras: DatabaseMessageExtra[]) => void;
+	setUploadedFiles: (files: ChatUploadedFile[]) => void;
+	save: () => void;
+	saveOnly: () => void;
+	cancel: () => void;
+	startEdit: () => void;
+}
+
+export type MessageEditContext = MessageEditState & MessageEditActions;
+
+const MESSAGE_EDIT_KEY = Symbol.for('chat-message-edit');
+
+/**
+ * Sets the message edit context. Call this in the parent component (ChatMessage.svelte).
+ */
+export function setMessageEditContext(ctx: MessageEditContext): MessageEditContext {
+	return setContext(MESSAGE_EDIT_KEY, ctx);
+}
+
+/**
+ * Gets the message edit context. Call this in child components.
+ */
+export function getMessageEditContext(): MessageEditContext {
+	return getContext(MESSAGE_EDIT_KEY);
+}

tools/server/webui/src/lib/enums/chat.ts

@@ -1,4 +1,51 @@
 export enum ChatMessageStatsView {
 	GENERATION = 'generation',
-	READING = 'reading'
+	READING = 'reading',
+	TOOLS = 'tools',
+	SUMMARY = 'summary'
+}
+
+/**
+ * Reasoning format options for API requests.
+ */
+export enum ReasoningFormat {
+	NONE = 'none',
+	AUTO = 'auto'
+}
+
+/**
+ * Message roles for chat messages.
+ */
+export enum MessageRole {
+	USER = 'user',
+	ASSISTANT = 'assistant',
+	SYSTEM = 'system',
+	TOOL = 'tool'
+}
+
+/**
+ * Message types for different content kinds.
+ */
+export enum MessageType {
+	ROOT = 'root',
+	TEXT = 'text',
+	THINK = 'think',
+	SYSTEM = 'system'
+}
+
+/**
+ * Content part types for API chat message content.
+ */
+export enum ContentPartType {
+	TEXT = 'text',
+	IMAGE_URL = 'image_url',
+	INPUT_AUDIO = 'input_audio'
+}
+
+/**
+ * Error dialog types for displaying server/timeout errors.
+ */
+export enum ErrorDialogType {
+	TIMEOUT = 'timeout',
+	SERVER = 'server'
 }

tools/server/webui/src/lib/enums/keyboard.ts

@@ -0,0 +1,15 @@
+/**
+ * Keyboard key names for event handling
+ */
+export enum KeyboardKey {
+	ENTER = 'Enter',
+	ESCAPE = 'Escape',
+	ARROW_UP = 'ArrowUp',
+	ARROW_DOWN = 'ArrowDown',
+	TAB = 'Tab',
+	D_LOWER = 'd',
+	D_UPPER = 'D',
+	E_UPPER = 'E',
+	K_LOWER = 'k',
+	O_UPPER = 'O'
+}

tools/server/webui/src/lib/enums/settings.ts

@@ -0,0 +1,26 @@
+/**
+ * Parameter source - indicates whether a parameter uses default or custom value
+ */
+export enum ParameterSource {
+	DEFAULT = 'default',
+	CUSTOM = 'custom'
+}
+
+/**
+ * Syncable parameter type - data types for parameters that can be synced with server
+ */
+export enum SyncableParameterType {
+	NUMBER = 'number',
+	STRING = 'string',
+	BOOLEAN = 'boolean'
+}
+
+/**
+ * Settings field type - defines the input type for settings fields
+ */
+export enum SettingsFieldType {
+	INPUT = 'input',
+	TEXTAREA = 'textarea',
+	CHECKBOX = 'checkbox',
+	SELECT = 'select'
+}

tools/server/webui/src/lib/hooks/use-auto-scroll.svelte.ts

@@ -0,0 +1,165 @@
+import { AUTO_SCROLL_AT_BOTTOM_THRESHOLD, AUTO_SCROLL_INTERVAL } from '$lib/constants/auto-scroll';
+
+export interface AutoScrollOptions {
+	/** Whether auto-scroll is disabled globally (e.g., from settings) */
+	disabled?: boolean;
+}
+
+/**
+ * Creates an auto-scroll controller for a scrollable container.
+ *
+ * Features:
+ * - Auto-scrolls to bottom during streaming/loading
+ * - Stops auto-scroll when user manually scrolls up
+ * - Resumes auto-scroll when user scrolls back to bottom
+ */
+export class AutoScrollController {
+	private _autoScrollEnabled = $state(true);
+	private _userScrolledUp = $state(false);
+	private _lastScrollTop = $state(0);
+	private _scrollInterval: ReturnType<typeof setInterval> | undefined;
+	private _scrollTimeout: ReturnType<typeof setTimeout> | undefined;
+	private _container: HTMLElement | undefined;
+	private _disabled: boolean;
+
+	constructor(options: AutoScrollOptions = {}) {
+		this._disabled = options.disabled ?? false;
+	}
+
+	get autoScrollEnabled(): boolean {
+		return this._autoScrollEnabled;
+	}
+
+	get userScrolledUp(): boolean {
+		return this._userScrolledUp;
+	}
+
+	/**
+	 * Binds the controller to a scrollable container element.
+	 */
+	setContainer(container: HTMLElement | undefined): void {
+		this._container = container;
+	}
+
+	/**
+	 * Updates the disabled state.
+	 */
+	setDisabled(disabled: boolean): void {
+		this._disabled = disabled;
+		if (disabled) {
+			this._autoScrollEnabled = false;
+			this.stopInterval();
+		}
+	}
+
+	/**
+	 * Handles scroll events to detect user scroll direction and toggle auto-scroll.
+	 */
+	handleScroll(): void {
+		if (this._disabled || !this._container) return;
+
+		const { scrollTop, scrollHeight, clientHeight } = this._container;
+		const distanceFromBottom = scrollHeight - scrollTop - clientHeight;
+		const isAtBottom = distanceFromBottom < AUTO_SCROLL_AT_BOTTOM_THRESHOLD;
+
+		if (scrollTop < this._lastScrollTop && !isAtBottom) {
+			this._userScrolledUp = true;
+			this._autoScrollEnabled = false;
+		} else if (isAtBottom && this._userScrolledUp) {
+			this._userScrolledUp = false;
+			this._autoScrollEnabled = true;
+		}
+
+		if (this._scrollTimeout) {
+			clearTimeout(this._scrollTimeout);
+		}
+
+		this._scrollTimeout = setTimeout(() => {
+			if (isAtBottom) {
+				this._userScrolledUp = false;
+				this._autoScrollEnabled = true;
+			}
+		}, AUTO_SCROLL_INTERVAL);
+
+		this._lastScrollTop = scrollTop;
+	}
+
+	/**
+	 * Scrolls the container to the bottom.
+	 */
+	scrollToBottom(behavior: ScrollBehavior = 'smooth'): void {
+		if (this._disabled || !this._container) return;
+
+		this._container.scrollTo({
+			top: this._container.scrollHeight,
+			behavior
+		});
+	}
+
+	/**
+	 * Enables auto-scroll (e.g., when user sends a message).
+	 */
+	enable(): void {
+		if (this._disabled) return;
+		this._userScrolledUp = false;
+		this._autoScrollEnabled = true;
+	}
+
+	/**
+	 * Starts the auto-scroll interval for continuous scrolling during streaming.
+	 */
+	startInterval(): void {
+		if (this._disabled || this._scrollInterval) return;
+
+		this._scrollInterval = setInterval(() => {
+			this.scrollToBottom();
+		}, AUTO_SCROLL_INTERVAL);
+	}
+
+	/**
+	 * Stops the auto-scroll interval.
+	 */
+	stopInterval(): void {
+		if (this._scrollInterval) {
+			clearInterval(this._scrollInterval);
+			this._scrollInterval = undefined;
+		}
+	}
+
+	/**
+	 * Updates the auto-scroll interval based on streaming state.
+	 * Call this in a $effect to automatically manage the interval.
+	 */
+	updateInterval(isStreaming: boolean): void {
+		if (this._disabled) {
+			this.stopInterval();
+			return;
+		}
+
+		if (isStreaming && this._autoScrollEnabled) {
+			if (!this._scrollInterval) {
+				this.startInterval();
+			}
+		} else {
+			this.stopInterval();
+		}
+	}
+
+	/**
+	 * Cleans up resources. Call this in onDestroy or when the component unmounts.
+	 */
+	destroy(): void {
+		this.stopInterval();
+		if (this._scrollTimeout) {
+			clearTimeout(this._scrollTimeout);
+			this._scrollTimeout = undefined;
+		}
+	}
+}
+
+/**
+ * Creates a new AutoScrollController instance.
+ */
+export function createAutoScrollController(options: AutoScrollOptions = {}): AutoScrollController {
+	return new AutoScrollController(options);
+}

tools/server/webui/src/lib/hooks/use-processing-state.svelte.ts

@@ -1,7 +1,9 @@
 import { activeProcessingState } from '$lib/stores/chat.svelte';
 import { config } from '$lib/stores/settings.svelte';
+import { STATS_UNITS } from '$lib/constants/processing-info';
+import type { ApiProcessingState } from '$lib/types';
 
-export interface LiveProcessingStats {
+interface LiveProcessingStats {
 	tokensProcessed: number;
 	totalTokens: number;
 	timeMs: number;
@@ -9,7 +11,7 @@ export interface LiveProcessingStats {
 	etaSecs?: number;
 }
 
-export interface LiveGenerationStats {
+interface LiveGenerationStats {
 	tokensGenerated: number;
 	timeMs: number;
 	tokensPerSecond: number;
@@ -18,6 +20,7 @@ export interface LiveGenerationStats {
 export interface UseProcessingStateReturn {
 	readonly processingState: ApiProcessingState | null;
 	getProcessingDetails(): string[];
+	getTechnicalDetails(): string[];
 	getProcessingMessage(): string;
 	getPromptProgressText(): string | null;
 	getLiveProcessingStats(): LiveProcessingStats | null;
@@ -138,8 +141,31 @@ export function useProcessingState(): UseProcessingStateReturn {
 
 		const details: string[] = [];
 
+		// Show prompt processing progress with ETA during preparation phase
+		if (stateToUse.promptProgress) {
+			const { processed, total, time_ms, cache } = stateToUse.promptProgress;
+			const actualProcessed = processed - cache;
+			const actualTotal = total - cache;
+
+			if (actualProcessed < actualTotal && actualProcessed > 0) {
+				const percent = Math.round((actualProcessed / actualTotal) * 100);
+				const eta = getETASecs(actualProcessed, actualTotal, time_ms);
+
+				if (eta !== undefined) {
+					const etaSecs = Math.ceil(eta);
+					details.push(`Processing ${percent}% (ETA: ${etaSecs}s)`);
+				} else {
+					details.push(`Processing ${percent}%`);
+				}
+			}
+		}
+
 		// Always show context info when we have valid data
-		if (stateToUse.contextUsed >= 0 && stateToUse.contextTotal > 0) {
+		if (
+			typeof stateToUse.contextTotal === 'number' &&
+			stateToUse.contextUsed >= 0 &&
+			stateToUse.contextTotal > 0
+		) {
 			const contextPercent = Math.round((stateToUse.contextUsed / stateToUse.contextTotal) * 100);
 
 			details.push(
@@ -163,7 +189,57 @@ export function useProcessingState(): UseProcessingStateReturn {
 		}
 
 		if (stateToUse.tokensPerSecond && stateToUse.tokensPerSecond > 0) {
-			details.push(`${stateToUse.tokensPerSecond.toFixed(1)} tokens/sec`);
+			details.push(`${stateToUse.tokensPerSecond.toFixed(1)} ${STATS_UNITS.TOKENS_PER_SECOND}`);
+		}
+
+		if (stateToUse.speculative) {
+			details.push('Speculative decoding enabled');
+		}
+
+		return details;
+	}
+
+	/**
+	 * Returns technical details without the progress message (for bottom bar)
+	 */
+	function getTechnicalDetails(): string[] {
+		const stateToUse = processingState || lastKnownState;
+		if (!stateToUse) {
+			return [];
+		}
+
+		const details: string[] = [];
+
+		// Always show context info when we have valid data
+		if (
+			typeof stateToUse.contextTotal === 'number' &&
+			stateToUse.contextUsed >= 0 &&
+			stateToUse.contextTotal > 0
+		) {
+			const contextPercent = Math.round((stateToUse.contextUsed / stateToUse.contextTotal) * 100);
+
+			details.push(
+				`Context: ${stateToUse.contextUsed}/${stateToUse.contextTotal} (${contextPercent}%)`
+			);
+		}
+
+		if (stateToUse.outputTokensUsed > 0) {
+			// Handle infinite max_tokens (-1) case
+			if (stateToUse.outputTokensMax <= 0) {
+				details.push(`Output: ${stateToUse.outputTokensUsed}/∞`);
+			} else {
+				const outputPercent = Math.round(
+					(stateToUse.outputTokensUsed / stateToUse.outputTokensMax) * 100
+				);
+
+				details.push(
+					`Output: ${stateToUse.outputTokensUsed}/${stateToUse.outputTokensMax} (${outputPercent}%)`
+				);
+			}
+		}
+
+		if (stateToUse.tokensPerSecond && stateToUse.tokensPerSecond > 0) {
+			details.push(`${stateToUse.tokensPerSecond.toFixed(1)} ${STATS_UNITS.TOKENS_PER_SECOND}`);
 		}
 
 		if (stateToUse.speculative) {
@@ -251,6 +327,7 @@ export function useProcessingState(): UseProcessingStateReturn {
 			return processingState;
 		},
 		getProcessingDetails,
+		getTechnicalDetails,
 		getProcessingMessage,
 		getPromptProgressText,
 		getLiveProcessingStats,

tools/server/webui/src/lib/markdown/enhance-code-blocks.ts

@@ -13,6 +13,16 @@
 import type { Plugin } from 'unified';
 import type { Root, Element, ElementContent } from 'hast';
 import { visit } from 'unist-util-visit';
+import {
+	CODE_BLOCK_SCROLL_CONTAINER_CLASS,
+	CODE_BLOCK_WRAPPER_CLASS,
+	CODE_BLOCK_HEADER_CLASS,
+	CODE_BLOCK_ACTIONS_CLASS,
+	CODE_LANGUAGE_CLASS,
+	COPY_CODE_BTN_CLASS,
+	PREVIEW_CODE_BTN_CLASS,
+	RELATIVE_CLASS
+} from '$lib/constants/code-blocks';
 
 declare global {
 	interface Window {
@@ -42,7 +52,7 @@ function createCopyButton(codeId: string): Element {
 		type: 'element',
 		tagName: 'button',
 		properties: {
-			className: ['copy-code-btn'],
+			className: [COPY_CODE_BTN_CLASS],
 			'data-code-id': codeId,
 			title: 'Copy code',
 			type: 'button'
@@ -56,7 +66,7 @@ function createPreviewButton(codeId: string): Element {
 		type: 'element',
 		tagName: 'button',
 		properties: {
-			className: ['preview-code-btn'],
+			className: [PREVIEW_CODE_BTN_CLASS],
 			'data-code-id': codeId,
 			title: 'Preview code',
 			type: 'button'
@@ -75,30 +85,39 @@ function createHeader(language: string, codeId: string): Element {
 	return {
 		type: 'element',
 		tagName: 'div',
-		properties: { className: ['code-block-header'] },
+		properties: { className: [CODE_BLOCK_HEADER_CLASS] },
 		children: [
 			{
 				type: 'element',
 				tagName: 'span',
-				properties: { className: ['code-language'] },
+				properties: { className: [CODE_LANGUAGE_CLASS] },
 				children: [{ type: 'text', value: language }]
 			},
 			{
 				type: 'element',
 				tagName: 'div',
-				properties: { className: ['code-block-actions'] },
+				properties: { className: [CODE_BLOCK_ACTIONS_CLASS] },
 				children: actions
 			}
 		]
 	};
 }
 
+function createScrollContainer(preElement: Element): Element {
+	return {
+		type: 'element',
+		tagName: 'div',
+		properties: { className: [CODE_BLOCK_SCROLL_CONTAINER_CLASS] },
+		children: [preElement]
+	};
+}
+
 function createWrapper(header: Element, preElement: Element): Element {
 	return {
 		type: 'element',
 		tagName: 'div',
-		properties: { className: ['code-block-wrapper'] },
-		children: [header, preElement]
+		properties: { className: [CODE_BLOCK_WRAPPER_CLASS, RELATIVE_CLASS] },
+		children: [header, createScrollContainer(preElement)]
 	};
 }
 

tools/server/webui/src/lib/services/database.service.ts

@@ -0,0 +1,368 @@
+import Dexie, { type EntityTable } from 'dexie';
+import { findDescendantMessages } from '$lib/utils';
+
+class LlamacppDatabase extends Dexie {
+	conversations!: EntityTable<DatabaseConversation, string>;
+	messages!: EntityTable<DatabaseMessage, string>;
+
+	constructor() {
+		super('LlamacppWebui');
+
+		this.version(1).stores({
+			conversations: 'id, lastModified, currNode, name',
+			messages: 'id, convId, type, role, timestamp, parent, children'
+		});
+	}
+}
+
+const db = new LlamacppDatabase();
+import { v4 as uuid } from 'uuid';
+import { MessageRole } from '$lib/enums/chat';
+
+export class DatabaseService {
+	/**
+	 *
+	 *
+	 * Conversations
+	 *
+	 *
+	 */
+
+	/**
+	 * Creates a new conversation.
+	 *
+	 * @param name - Name of the conversation
+	 * @returns The created conversation
+	 */
+	static async createConversation(name: string): Promise<DatabaseConversation> {
+		const conversation: DatabaseConversation = {
+			id: uuid(),
+			name,
+			lastModified: Date.now(),
+			currNode: ''
+		};
+
+		await db.conversations.add(conversation);
+		return conversation;
+	}
+
+	/**
+	 *
+	 *
+	 * Messages
+	 *
+	 *
+	 */
+
+	/**
+	 * Creates a new message branch by adding a message and updating parent/child relationships.
+	 * Also updates the conversation's currNode to point to the new message.
+	 *
+	 * @param message - Message to add (without id)
+	 * @param parentId - Parent message ID to attach to
+	 * @returns The created message
+	 */
+	static async createMessageBranch(
+		message: Omit<DatabaseMessage, 'id'>,
+		parentId: string | null
+	): Promise<DatabaseMessage> {
+		return await db.transaction('rw', [db.conversations, db.messages], async () => {
+			// Handle null parent (root message case)
+			if (parentId !== null) {
+				const parentMessage = await db.messages.get(parentId);
+				if (!parentMessage) {
+					throw new Error(`Parent message ${parentId} not found`);
+				}
+			}
+
+			const newMessage: DatabaseMessage = {
+				...message,
+				id: uuid(),
+				parent: parentId,
+				toolCalls: message.toolCalls ?? '',
+				children: []
+			};
+
+			await db.messages.add(newMessage);
+
+			// Update parent's children array if parent exists
+			if (parentId !== null) {
+				const parentMessage = await db.messages.get(parentId);
+				if (parentMessage) {
+					await db.messages.update(parentId, {
+						children: [...parentMessage.children, newMessage.id]
+					});
+				}
+			}
+
+			await this.updateConversation(message.convId, {
+				currNode: newMessage.id
+			});
+
+			return newMessage;
+		});
+	}
+
+	/**
+	 * Creates a root message for a new conversation.
+	 * Root messages are not displayed but serve as the tree root for branching.
+	 *
+	 * @param convId - Conversation ID
+	 * @returns The created root message
+	 */
+	static async createRootMessage(convId: string): Promise<string> {
+		const rootMessage: DatabaseMessage = {
+			id: uuid(),
+			convId,
+			type: 'root',
+			timestamp: Date.now(),
+			role: MessageRole.SYSTEM,
+			content: '',
+			parent: null,
+			toolCalls: '',
+			children: []
+		};
+
+		await db.messages.add(rootMessage);
+		return rootMessage.id;
+	}
+
+	/**
+	 * Creates a system prompt message for a conversation.
+	 *
+	 * @param convId - Conversation ID
+	 * @param systemPrompt - The system prompt content (must be non-empty)
+	 * @param parentId - Parent message ID (typically the root message)
+	 * @returns The created system message
+	 * @throws Error if systemPrompt is empty
+	 */
+	static async createSystemMessage(
+		convId: string,
+		systemPrompt: string,
+		parentId: string
+	): Promise<DatabaseMessage> {
+		const trimmedPrompt = systemPrompt.trim();
+		if (!trimmedPrompt) {
+			throw new Error('Cannot create system message with empty content');
+		}
+
+		const systemMessage: DatabaseMessage = {
+			id: uuid(),
+			convId,
+			type: MessageRole.SYSTEM,
+			timestamp: Date.now(),
+			role: MessageRole.SYSTEM,
+			content: trimmedPrompt,
+			parent: parentId,
+			children: []
+		};
+
+		await db.messages.add(systemMessage);
+
+		const parentMessage = await db.messages.get(parentId);
+		if (parentMessage) {
+			await db.messages.update(parentId, {
+				children: [...parentMessage.children, systemMessage.id]
+			});
+		}
+
+		return systemMessage;
+	}
+
+	/**
+	 * Deletes a conversation and all its messages.
+	 *
+	 * @param id - Conversation ID
+	 */
+	static async deleteConversation(id: string): Promise<void> {
+		await db.transaction('rw', [db.conversations, db.messages], async () => {
+			await db.conversations.delete(id);
+			await db.messages.where('convId').equals(id).delete();
+		});
+	}
+
+	/**
+	 * Deletes a message and removes it from its parent's children array.
+	 *
+	 * @param messageId - ID of the message to delete
+	 */
+	static async deleteMessage(messageId: string): Promise<void> {
+		await db.transaction('rw', db.messages, async () => {
+			const message = await db.messages.get(messageId);
+			if (!message) return;
+
+			// Remove this message from its parent's children array
+			if (message.parent) {
+				const parent = await db.messages.get(message.parent);
+				if (parent) {
+					parent.children = parent.children.filter((childId: string) => childId !== messageId);
+					await db.messages.put(parent);
+				}
+			}
+
+			// Delete the message
+			await db.messages.delete(messageId);
+		});
+	}
+
+	/**
+	 * Deletes a message and all its descendant messages (cascading deletion).
+	 * This removes the entire branch starting from the specified message.
+	 *
+	 * @param conversationId - ID of the conversation containing the message
+	 * @param messageId - ID of the root message to delete (along with all descendants)
+	 * @returns Array of all deleted message IDs
+	 */
+	static async deleteMessageCascading(
+		conversationId: string,
+		messageId: string
+	): Promise<string[]> {
+		return await db.transaction('rw', db.messages, async () => {
+			// Get all messages in the conversation to find descendants
+			const allMessages = await db.messages.where('convId').equals(conversationId).toArray();
+
+			// Find all descendant messages
+			const descendants = findDescendantMessages(allMessages, messageId);
+			const allToDelete = [messageId, ...descendants];
+
+			// Get the message to delete for parent cleanup
+			const message = await db.messages.get(messageId);
+			if (message && message.parent) {
+				const parent = await db.messages.get(message.parent);
+				if (parent) {
+					parent.children = parent.children.filter((childId: string) => childId !== messageId);
+					await db.messages.put(parent);
+				}
+			}
+
+			// Delete all messages in the branch
+			await db.messages.bulkDelete(allToDelete);
+
+			return allToDelete;
+		});
+	}
+
+	/**
+	 * Gets all conversations, sorted by last modified time (newest first).
+	 *
+	 * @returns Array of conversations
+	 */
+	static async getAllConversations(): Promise<DatabaseConversation[]> {
+		return await db.conversations.orderBy('lastModified').reverse().toArray();
+	}
+
+	/**
+	 * Gets a conversation by ID.
+	 *
+	 * @param id - Conversation ID
+	 * @returns The conversation if found, otherwise undefined
+	 */
+	static async getConversation(id: string): Promise<DatabaseConversation | undefined> {
+		return await db.conversations.get(id);
+	}
+
+	/**
+	 * Gets all messages in a conversation, sorted by timestamp (oldest first).
+	 *
+	 * @param convId - Conversation ID
+	 * @returns Array of messages in the conversation
+	 */
+	static async getConversationMessages(convId: string): Promise<DatabaseMessage[]> {
+		return await db.messages.where('convId').equals(convId).sortBy('timestamp');
+	}
+
+	/**
+	 * Updates a conversation.
+	 *
+	 * @param id - Conversation ID
+	 * @param updates - Partial updates to apply
+	 * @returns Promise that resolves when the conversation is updated
+	 */
+	static async updateConversation(
+		id: string,
+		updates: Partial<Omit<DatabaseConversation, 'id'>>
+	): Promise<void> {
+		await db.conversations.update(id, {
+			...updates,
+			lastModified: Date.now()
+		});
+	}
+
+	/**
+	 *
+	 *
+	 * Navigation
+	 *
+	 *
+	 */
+
+	/**
+	 * Updates the conversation's current node (active branch).
+	 * This determines which conversation path is currently being viewed.
+	 *
+	 * @param convId - Conversation ID
+	 * @param nodeId - Message ID to set as current node
+	 */
+	static async updateCurrentNode(convId: string, nodeId: string): Promise<void> {
+		await this.updateConversation(convId, {
+			currNode: nodeId
+		});
+	}
+
+	/**
+	 * Updates a message.
+	 *
+	 * @param id - Message ID
+	 * @param updates - Partial updates to apply
+	 * @returns Promise that resolves when the message is updated
+	 */
+	static async updateMessage(
+		id: string,
+		updates: Partial<Omit<DatabaseMessage, 'id'>>
+	): Promise<void> {
+		await db.messages.update(id, updates);
+	}
+
+	/**
+	 *
+	 *
+	 * Import
+	 *
+	 *
+	 */
+
+	/**
+	 * Imports multiple conversations and their messages.
+	 * Skips conversations that already exist.
+	 *
+	 * @param data - Array of { conv, messages } objects
+	 */
+	static async importConversations(
+		data: { conv: DatabaseConversation; messages: DatabaseMessage[] }[]
+	): Promise<{ imported: number; skipped: number }> {
+		let importedCount = 0;
+		let skippedCount = 0;
+
+		return await db.transaction('rw', [db.conversations, db.messages], async () => {
+			for (const item of data) {
+				const { conv, messages } = item;
+
+				const existing = await db.conversations.get(conv.id);
+				if (existing) {
+					console.warn(`Conversation "${conv.name}" already exists, skipping...`);
+					skippedCount++;
+					continue;
+				}
+
+				await db.conversations.add(conv);
+				for (const msg of messages) {
+					await db.messages.put(msg);
+				}
+
+				importedCount++;
+			}
+
+			return { imported: importedCount, skipped: skippedCount };
+		});
+	}
+}

tools/server/webui/src/lib/services/models.service.ts

@@ -0,0 +1,99 @@
+import { ServerModelStatus } from '$lib/enums';
+import { apiFetch, apiPost } from '$lib/utils/api-fetch';
+
+export class ModelsService {
+	/**
+	 *
+	 *
+	 * Listing
+	 *
+	 *
+	 */
+
+	/**
+	 * Fetch list of models from OpenAI-compatible endpoint.
+	 * Works in both MODEL and ROUTER modes.
+	 *
+	 * @returns List of available models with basic metadata
+	 */
+	static async list(): Promise<ApiModelListResponse> {
+		return apiFetch<ApiModelListResponse>('/v1/models');
+	}
+
+	/**
+	 * Fetch list of all models with detailed metadata (ROUTER mode).
+	 * Returns models with load status, paths, and other metadata
+	 * beyond what the OpenAI-compatible endpoint provides.
+	 *
+	 * @returns List of models with detailed status and configuration info
+	 */
+	static async listRouter(): Promise<ApiRouterModelsListResponse> {
+		return apiFetch<ApiRouterModelsListResponse>('/v1/models');
+	}
+
+	/**
+	 *
+	 *
+	 * Load/Unload
+	 *
+	 *
+	 */
+
+	/**
+	 * Load a model (ROUTER mode only).
+	 * Sends POST request to `/models/load`. Note: the endpoint returns success
+	 * before loading completes — use polling to await actual load status.
+	 *
+	 * @param modelId - Model identifier to load
+	 * @param extraArgs - Optional additional arguments to pass to the model instance
+	 * @returns Load response from the server
+	 */
+	static async load(modelId: string, extraArgs?: string[]): Promise<ApiRouterModelsLoadResponse> {
+		const payload: { model: string; extra_args?: string[] } = { model: modelId };
+		if (extraArgs && extraArgs.length > 0) {
+			payload.extra_args = extraArgs;
+		}
+
+		return apiPost<ApiRouterModelsLoadResponse>('/models/load', payload);
+	}
+
+	/**
+	 * Unload a model (ROUTER mode only).
+	 * Sends POST request to `/models/unload`. Note: the endpoint returns success
+	 * before unloading completes — use polling to await actual unload status.
+	 *
+	 * @param modelId - Model identifier to unload
+	 * @returns Unload response from the server
+	 */
+	static async unload(modelId: string): Promise<ApiRouterModelsUnloadResponse> {
+		return apiPost<ApiRouterModelsUnloadResponse>('/models/unload', { model: modelId });
+	}
+
+	/**
+	 *
+	 *
+	 * Status
+	 *
+	 *
+	 */
+
+	/**
+	 * Check if a model is loaded based on its metadata.
+	 *
+	 * @param model - Model data entry from the API response
+	 * @returns True if the model status is LOADED
+	 */
+	static isModelLoaded(model: ApiModelDataEntry): boolean {
+		return model.status.value === ServerModelStatus.LOADED;
+	}
+
+	/**
+	 * Check if a model is currently loading.
+	 *
+	 * @param model - Model data entry from the API response
+	 * @returns True if the model status is LOADING
+	 */
+	static isModelLoading(model: ApiModelDataEntry): boolean {
+		return model.status.value === ServerModelStatus.LOADING;
+	}
+}

tools/server/webui/src/lib/services/parameter-sync.service.spec.ts

@@ -0,0 +1,148 @@
+import { describe, it, expect } from 'vitest';
+import { ParameterSyncService } from './parameter-sync.service';
+
+describe('ParameterSyncService', () => {
+	describe('roundFloatingPoint', () => {
+		it('should fix JavaScript floating-point precision issues', () => {
+			// Test the specific values from the screenshot
+			const mockServerParams = {
+				top_p: 0.949999988079071,
+				min_p: 0.009999999776482582,
+				temperature: 0.800000011920929,
+				top_k: 40,
+				samplers: ['top_k', 'typ_p', 'top_p', 'min_p', 'temperature']
+			};
+
+			const result = ParameterSyncService.extractServerDefaults({
+				...mockServerParams,
+				// Add other required fields to match the API type
+				n_predict: 512,
+				seed: -1,
+				dynatemp_range: 0.0,
+				dynatemp_exponent: 1.0,
+				xtc_probability: 0.0,
+				xtc_threshold: 0.1,
+				typ_p: 1.0,
+				repeat_last_n: 64,
+				repeat_penalty: 1.0,
+				presence_penalty: 0.0,
+				frequency_penalty: 0.0,
+				dry_multiplier: 0.0,
+				dry_base: 1.75,
+				dry_allowed_length: 2,
+				dry_penalty_last_n: -1,
+				mirostat: 0,
+				mirostat_tau: 5.0,
+				mirostat_eta: 0.1,
+				stop: [],
+				max_tokens: -1,
+				n_keep: 0,
+				n_discard: 0,
+				ignore_eos: false,
+				stream: true,
+				logit_bias: [],
+				n_probs: 0,
+				min_keep: 0,
+				grammar: '',
+				grammar_lazy: false,
+				grammar_triggers: [],
+				preserved_tokens: [],
+				chat_format: '',
+				reasoning_format: '',
+				reasoning_in_content: false,
+				thinking_forced_open: false,
+				'speculative.n_max': 0,
+				'speculative.n_min': 0,
+				'speculative.p_min': 0.0,
+				timings_per_token: false,
+				post_sampling_probs: false,
+				lora: [],
+				top_n_sigma: 0.0,
+				dry_sequence_breakers: []
+			} as ApiLlamaCppServerProps['default_generation_settings']['params']);
+
+			// Check that the problematic floating-point values are rounded correctly
+			expect(result.top_p).toBe(0.95);
+			expect(result.min_p).toBe(0.01);
+			expect(result.temperature).toBe(0.8);
+			expect(result.top_k).toBe(40); // Integer should remain unchanged
+			expect(result.samplers).toBe('top_k;typ_p;top_p;min_p;temperature');
+		});
+
+		it('should preserve non-numeric values', () => {
+			const mockServerParams = {
+				samplers: ['top_k', 'temperature'],
+				max_tokens: -1,
+				temperature: 0.7
+			};
+
+			const result = ParameterSyncService.extractServerDefaults({
+				...mockServerParams,
+				// Minimal required fields
+				n_predict: 512,
+				seed: -1,
+				dynatemp_range: 0.0,
+				dynatemp_exponent: 1.0,
+				top_k: 40,
+				top_p: 0.95,
+				min_p: 0.05,
+				xtc_probability: 0.0,
+				xtc_threshold: 0.1,
+				typ_p: 1.0,
+				repeat_last_n: 64,
+				repeat_penalty: 1.0,
+				presence_penalty: 0.0,
+				frequency_penalty: 0.0,
+				dry_multiplier: 0.0,
+				dry_base: 1.75,
+				dry_allowed_length: 2,
+				dry_penalty_last_n: -1,
+				mirostat: 0,
+				mirostat_tau: 5.0,
+				mirostat_eta: 0.1,
+				stop: [],
+				n_keep: 0,
+				n_discard: 0,
+				ignore_eos: false,
+				stream: true,
+				logit_bias: [],
+				n_probs: 0,
+				min_keep: 0,
+				grammar: '',
+				grammar_lazy: false,
+				grammar_triggers: [],
+				preserved_tokens: [],
+				chat_format: '',
+				reasoning_format: '',
+				reasoning_in_content: false,
+				thinking_forced_open: false,
+				'speculative.n_max': 0,
+				'speculative.n_min': 0,
+				'speculative.p_min': 0.0,
+				timings_per_token: false,
+				post_sampling_probs: false,
+				lora: [],
+				top_n_sigma: 0.0,
+				dry_sequence_breakers: []
+			} as ApiLlamaCppServerProps['default_generation_settings']['params']);
+
+			expect(result.samplers).toBe('top_k;temperature');
+			expect(result.max_tokens).toBe(-1);
+			expect(result.temperature).toBe(0.7);
+		});
+
+		it('should merge webui settings from props when provided', () => {
+			const result = ParameterSyncService.extractServerDefaults(null, {
+				pasteLongTextToFileLen: 0,
+				pdfAsImage: true,
+				renderUserContentAsMarkdown: false,
+				theme: 'dark'
+			});
+
+			expect(result.pasteLongTextToFileLen).toBe(0);
+			expect(result.pdfAsImage).toBe(true);
+			expect(result.renderUserContentAsMarkdown).toBe(false);
+			expect(result.theme).toBeUndefined();
+		});
+	});
+});

tools/server/webui/src/lib/services/parameter-sync.service.ts

@@ -0,0 +1,400 @@
+import { normalizeFloatingPoint } from '$lib/utils';
+import { SyncableParameterType, ParameterSource } from '$lib/enums/settings';
+
+type ParameterValue = string | number | boolean;
+type ParameterRecord = Record<string, ParameterValue>;
+
+interface ParameterInfo {
+	value: string | number | boolean;
+	source: ParameterSource;
+	serverDefault?: string | number | boolean;
+	userOverride?: string | number | boolean;
+}
+
+interface SyncableParameter {
+	key: string;
+	serverKey: string;
+	type: SyncableParameterType;
+	canSync: boolean;
+}
+
+/**
+ * Mapping of webui setting keys to server parameter keys.
+ * Only parameters listed here can be synced from the server `/props` endpoint.
+ * Each entry defines the webui key, corresponding server key, value type,
+ * and whether sync is enabled.
+ */
+export const SYNCABLE_PARAMETERS: SyncableParameter[] = [
+	{
+		key: 'temperature',
+		serverKey: 'temperature',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{ key: 'top_k', serverKey: 'top_k', type: SyncableParameterType.NUMBER, canSync: true },
+	{ key: 'top_p', serverKey: 'top_p', type: SyncableParameterType.NUMBER, canSync: true },
+	{ key: 'min_p', serverKey: 'min_p', type: SyncableParameterType.NUMBER, canSync: true },
+	{
+		key: 'dynatemp_range',
+		serverKey: 'dynatemp_range',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'dynatemp_exponent',
+		serverKey: 'dynatemp_exponent',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'xtc_probability',
+		serverKey: 'xtc_probability',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'xtc_threshold',
+		serverKey: 'xtc_threshold',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{ key: 'typ_p', serverKey: 'typ_p', type: SyncableParameterType.NUMBER, canSync: true },
+	{
+		key: 'repeat_last_n',
+		serverKey: 'repeat_last_n',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'repeat_penalty',
+		serverKey: 'repeat_penalty',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'presence_penalty',
+		serverKey: 'presence_penalty',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'frequency_penalty',
+		serverKey: 'frequency_penalty',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'dry_multiplier',
+		serverKey: 'dry_multiplier',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{ key: 'dry_base', serverKey: 'dry_base', type: SyncableParameterType.NUMBER, canSync: true },
+	{
+		key: 'dry_allowed_length',
+		serverKey: 'dry_allowed_length',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'dry_penalty_last_n',
+		serverKey: 'dry_penalty_last_n',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{ key: 'max_tokens', serverKey: 'max_tokens', type: SyncableParameterType.NUMBER, canSync: true },
+	{ key: 'samplers', serverKey: 'samplers', type: SyncableParameterType.STRING, canSync: true },
+	{
+		key: 'pasteLongTextToFileLen',
+		serverKey: 'pasteLongTextToFileLen',
+		type: SyncableParameterType.NUMBER,
+		canSync: true
+	},
+	{
+		key: 'pdfAsImage',
+		serverKey: 'pdfAsImage',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'showThoughtInProgress',
+		serverKey: 'showThoughtInProgress',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'keepStatsVisible',
+		serverKey: 'keepStatsVisible',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'showMessageStats',
+		serverKey: 'showMessageStats',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'askForTitleConfirmation',
+		serverKey: 'askForTitleConfirmation',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'disableAutoScroll',
+		serverKey: 'disableAutoScroll',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'renderUserContentAsMarkdown',
+		serverKey: 'renderUserContentAsMarkdown',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'autoMicOnEmpty',
+		serverKey: 'autoMicOnEmpty',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'pyInterpreterEnabled',
+		serverKey: 'pyInterpreterEnabled',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	},
+	{
+		key: 'enableContinueGeneration',
+		serverKey: 'enableContinueGeneration',
+		type: SyncableParameterType.BOOLEAN,
+		canSync: true
+	}
+];
+
+export class ParameterSyncService {
+	/**
+	 *
+	 *
+	 * Extraction
+	 *
+	 *
+	 */
+
+	/**
+	 * Round floating-point numbers to avoid JavaScript precision issues.
+	 * E.g., 0.1 + 0.2 = 0.30000000000000004 → 0.3
+	 *
+	 * @param value - Parameter value to normalize
+	 * @returns Precision-normalized value
+	 */
+	private static roundFloatingPoint(value: ParameterValue): ParameterValue {
+		return normalizeFloatingPoint(value) as ParameterValue;
+	}
+
+	/**
+	 * Extract server default parameters that can be synced from `/props` response.
+	 * Handles both generation settings parameters and webui-specific settings.
+	 * Converts samplers array to semicolon-delimited string for UI display.
+	 *
+	 * @param serverParams - Raw generation settings from server `/props` endpoint
+	 * @param webuiSettings - Optional webui-specific settings from server
+	 * @returns Record of extracted parameter key-value pairs with normalized precision
+	 */
+	static extractServerDefaults(
+		serverParams: ApiLlamaCppServerProps['default_generation_settings']['params'] | null,
+		webuiSettings?: Record<string, string | number | boolean>
+	): ParameterRecord {
+		const extracted: ParameterRecord = {};
+
+		if (serverParams) {
+			for (const param of SYNCABLE_PARAMETERS) {
+				if (param.canSync && param.serverKey in serverParams) {
+					const value = (serverParams as unknown as Record<string, ParameterValue>)[
+						param.serverKey
+					];
+					if (value !== undefined) {
+						// Apply precision rounding to avoid JavaScript floating-point issues
+						extracted[param.key] = this.roundFloatingPoint(value);
+					}
+				}
+			}
+
+			// Handle samplers array conversion to string
+			if (serverParams.samplers && Array.isArray(serverParams.samplers)) {
+				extracted.samplers = serverParams.samplers.join(';');
+			}
+		}
+
+		if (webuiSettings) {
+			for (const param of SYNCABLE_PARAMETERS) {
+				if (param.canSync && param.serverKey in webuiSettings) {
+					const value = webuiSettings[param.serverKey];
+					if (value !== undefined) {
+						extracted[param.key] = this.roundFloatingPoint(value);
+					}
+				}
+			}
+		}
+
+		return extracted;
+	}
+
+	/**
+	 *
+	 *
+	 * Merging
+	 *
+	 *
+	 */
+
+	/**
+	 * Merge server defaults with current user settings.
+	 * User overrides always take priority — only parameters not in `userOverrides`
+	 * set will be updated from server defaults.
+	 *
+	 * @param currentSettings - Current parameter values in the settings store
+	 * @param serverDefaults - Default values extracted from server props
+	 * @param userOverrides - Set of parameter keys explicitly overridden by the user
+	 * @returns Merged parameter record with user overrides preserved
+	 */
+	static mergeWithServerDefaults(
+		currentSettings: ParameterRecord,
+		serverDefaults: ParameterRecord,
+		userOverrides: Set<string> = new Set()
+	): ParameterRecord {
+		const merged = { ...currentSettings };
+
+		for (const [key, serverValue] of Object.entries(serverDefaults)) {
+			// Only update if user hasn't explicitly overridden this parameter
+			if (!userOverrides.has(key)) {
+				merged[key] = this.roundFloatingPoint(serverValue);
+			}
+		}
+
+		return merged;
+	}
+
+	/**
+	 *
+	 *
+	 * Info
+	 *
+	 *
+	 */
+
+	/**
+	 * Get parameter information including source and values.
+	 * Used by ChatSettingsParameterSourceIndicator to display the correct badge
+	 * (Custom vs Default) for each parameter in the settings UI.
+	 *
+	 * @param key - The parameter key to get info for
+	 * @param currentValue - The current value of the parameter
+	 * @param propsDefaults - Server default values from `/props`
+	 * @param userOverrides - Set of parameter keys explicitly overridden by the user
+	 * @returns Parameter info with source, server default, and user override values
+	 */
+	static getParameterInfo(
+		key: string,
+		currentValue: ParameterValue,
+		propsDefaults: ParameterRecord,
+		userOverrides: Set<string>
+	): ParameterInfo {
+		const hasPropsDefault = propsDefaults[key] !== undefined;
+		const isUserOverride = userOverrides.has(key);
+
+		// Simple logic: either using default (from props) or custom (user override)
+		const source = isUserOverride ? ParameterSource.CUSTOM : ParameterSource.DEFAULT;
+
+		return {
+			value: currentValue,
+			source,
+			serverDefault: hasPropsDefault ? propsDefaults[key] : undefined, // Keep same field name for compatibility
+			userOverride: isUserOverride ? currentValue : undefined
+		};
+	}
+
+	/**
+	 * Check if a parameter can be synced from server.
+	 *
+	 * @param key - The parameter key to check
+	 * @returns True if the parameter is in the syncable parameters list
+	 */
+	static canSyncParameter(key: string): boolean {
+		return SYNCABLE_PARAMETERS.some((param) => param.key === key && param.canSync);
+	}
+
+	/**
+	 * Get all syncable parameter keys.
+	 *
+	 * @returns Array of parameter keys that can be synced from server
+	 */
+	static getSyncableParameterKeys(): string[] {
+		return SYNCABLE_PARAMETERS.filter((param) => param.canSync).map((param) => param.key);
+	}
+
+	/**
+	 * Validate a server parameter value against its expected type.
+	 *
+	 * @param key - The parameter key to validate
+	 * @param value - The value to validate
+	 * @returns True if value matches the expected type for this parameter
+	 */
+	static validateServerParameter(key: string, value: ParameterValue): boolean {
+		const param = SYNCABLE_PARAMETERS.find((p) => p.key === key);
+		if (!param) return false;
+
+		switch (param.type) {
+			case SyncableParameterType.NUMBER:
+				return typeof value === 'number' && !isNaN(value);
+			case SyncableParameterType.STRING:
+				return typeof value === 'string';
+			case SyncableParameterType.BOOLEAN:
+				return typeof value === 'boolean';
+			default:
+				return false;
+		}
+	}
+
+	/**
+	 *
+	 *
+	 * Diff
+	 *
+	 *
+	 */
+
+	/**
+	 * Create a diff between current settings and server defaults.
+	 * Shows which parameters differ from server values, useful for debugging
+	 * and for the "Reset to defaults" functionality.
+	 *
+	 * @param currentSettings - Current parameter values in the settings store
+	 * @param serverDefaults - Default values extracted from server props
+	 * @returns Record of parameter diffs with current value, server value, and whether they differ
+	 */
+	static createParameterDiff(
+		currentSettings: ParameterRecord,
+		serverDefaults: ParameterRecord
+	): Record<string, { current: ParameterValue; server: ParameterValue; differs: boolean }> {
+		const diff: Record<
+			string,
+			{ current: ParameterValue; server: ParameterValue; differs: boolean }
+		> = {};
+
+		for (const key of this.getSyncableParameterKeys()) {
+			const currentValue = currentSettings[key];
+			const serverValue = serverDefaults[key];
+
+			if (serverValue !== undefined) {
+				diff[key] = {
+					current: currentValue,
+					server: serverValue,
+					differs: currentValue !== serverValue
+				};
+			}
+		}
+
+		return diff;
+	}
+}

tools/server/webui/src/lib/services/props.service.ts

@@ -0,0 +1,47 @@
+import { apiFetchWithParams } from '$lib/utils/api-fetch';
+
+export class PropsService {
+	/**
+	 *
+	 *
+	 * Fetching
+	 *
+	 *
+	 */
+
+	/**
+	 * Fetches global server properties from the `/props` endpoint.
+	 * In MODEL mode, returns modalities for the single loaded model.
+	 * In ROUTER mode, returns server-wide settings without model-specific modalities.
+	 *
+	 * @param autoload - If false, prevents automatic model loading (default: false)
+	 * @returns Server properties including default generation settings and capabilities
+	 * @throws {Error} If the request fails or returns invalid data
+	 */
+	static async fetch(autoload = false): Promise<ApiLlamaCppServerProps> {
+		const params: Record<string, string> = {};
+		if (!autoload) {
+			params.autoload = 'false';
+		}
+
+		return apiFetchWithParams<ApiLlamaCppServerProps>('./props', params, { authOnly: true });
+	}
+
+	/**
+	 * Fetches server properties for a specific model (ROUTER mode only).
+	 * Required in ROUTER mode because global `/props` does not include per-model modalities.
+	 *
+	 * @param modelId - The model ID to fetch properties for
+	 * @param autoload - If false, prevents automatic model loading (default: false)
+	 * @returns Server properties specific to the requested model
+	 * @throws {Error} If the request fails, model not found, or model not loaded
+	 */
+	static async fetchForModel(modelId: string, autoload = false): Promise<ApiLlamaCppServerProps> {
+		const params: Record<string, string> = { model: modelId };
+		if (!autoload) {
+			params.autoload = 'false';
+		}
+
+		return apiFetchWithParams<ApiLlamaCppServerProps>('./props', params, { authOnly: true });
+	}
+}

tools/server/webui/src/lib/types/api.d.ts

@@ -1,8 +1,19 @@
-import type { ServerModelStatus, ServerRole } from '$lib/enums';
-import type { ChatMessagePromptProgress } from './chat';
+import type { ContentPartType, ServerModelStatus, ServerRole } from '$lib/enums';
+import type { ChatMessagePromptProgress, ChatRole } from './chat';
+
+export interface ApiChatCompletionToolFunction {
+	name: string;
+	description?: string;
+	parameters: Record<string, unknown>;
+}
+
+export interface ApiChatCompletionTool {
+	type: 'function';
+	function: ApiChatCompletionToolFunction;
+}
 
 export interface ApiChatMessageContentPart {
-	type: 'text' | 'image_url' | 'input_audio';
+	type: ContentPartType;
 	text?: string;
 	image_url?: {
 		url: string;
@@ -34,6 +45,8 @@ export interface ApiErrorResponse {
 export interface ApiChatMessageData {
 	role: ChatRole;
 	content: string | ApiChatMessageContentPart[];
+	tool_calls?: ApiChatCompletionToolCall[];
+	tool_call_id?: string;
 	timestamp?: number;
 }
 
@@ -188,6 +201,7 @@ export interface ApiChatCompletionRequest {
 	stream?: boolean;
 	model?: string;
 	return_progress?: boolean;
+	tools?: ApiChatCompletionTool[];
 	// Reasoning parameters
 	reasoning_format?: string;
 	// Generation parameters
@@ -247,6 +261,7 @@ export interface ApiChatCompletionStreamChunk {
 			model?: string;
 			tool_calls?: ApiChatCompletionToolCallDelta[];
 		};
+		finish_reason?: string | null;
 	}>;
 	timings?: {
 		prompt_n?: number;
@@ -267,8 +282,9 @@ export interface ApiChatCompletionResponse {
 			content: string;
 			reasoning_content?: string;
 			model?: string;
-			tool_calls?: ApiChatCompletionToolCallDelta[];
+			tool_calls?: ApiChatCompletionToolCall[];
 		};
+		finish_reason?: string | null;
 	}>;
 }
 
@@ -335,7 +351,7 @@ export interface ApiProcessingState {
 	tokensDecoded: number;
 	tokensRemaining: number;
 	contextUsed: number;
-	contextTotal: number;
+	contextTotal: number | null;
 	outputTokensUsed: number; // Total output tokens (thinking + regular content)
 	outputTokensMax: number; // Max output tokens allowed
 	temperature: number;

tools/server/webui/src/lib/types/models.d.ts

@@ -1,8 +1,5 @@
 import type { ApiModelDataEntry, ApiModelDetails } from '$lib/types/api';
 
-/**
- * Model modalities - vision and audio capabilities
- */
 export interface ModelModalities {
 	vision: boolean;
 	audio: boolean;
@@ -14,8 +11,15 @@ export interface ModelOption {
 	model: string;
 	description?: string;
 	capabilities: string[];
-	/** Model modalities from /props endpoint */
 	modalities?: ModelModalities;
 	details?: ApiModelDetails['details'];
 	meta?: ApiModelDataEntry['meta'];
 }
+
+/**
+ * Modality capabilities for file validation
+ */
+export interface ModalityCapabilities {
+	hasVision: boolean;
+	hasAudio: boolean;
+}

tools/server/webui/src/lib/utils/abort.ts

@@ -0,0 +1,151 @@
+/**
+ * Abort Signal Utilities
+ *
+ * Provides utilities for consistent AbortSignal propagation across the application.
+ * These utilities help ensure that async operations can be properly cancelled
+ * when needed (e.g., user stops generation, navigates away, etc.).
+ */
+
+/**
+ * Throws an AbortError if the signal is aborted.
+ * Use this at the start of async operations to fail fast.
+ *
+ * @param signal - Optional AbortSignal to check
+ * @throws DOMException with name 'AbortError' if signal is aborted
+ *
+ * @example
+ * ```ts
+ * async function fetchData(signal?: AbortSignal) {
+ *   throwIfAborted(signal);
+ *   // ... proceed with operation
+ * }
+ * ```
+ */
+export function throwIfAborted(signal?: AbortSignal): void {
+	if (signal?.aborted) {
+		throw new DOMException('Operation was aborted', 'AbortError');
+	}
+}
+
+/**
+ * Checks if an error is an AbortError.
+ * Use this to distinguish between user-initiated cancellation and actual errors.
+ *
+ * @param error - Error to check
+ * @returns true if the error is an AbortError
+ *
+ * @example
+ * ```ts
+ * try {
+ *   await fetchData(signal);
+ * } catch (error) {
+ *   if (isAbortError(error)) {
+ *     // User cancelled - no error dialog needed
+ *     return;
+ *   }
+ *   // Handle actual error
+ * }
+ * ```
+ */
+export function isAbortError(error: unknown): boolean {
+	if (error instanceof DOMException && error.name === 'AbortError') {
+		return true;
+	}
+	if (error instanceof Error && error.name === 'AbortError') {
+		return true;
+	}
+	return false;
+}
+
+/**
+ * Creates a new AbortController that is linked to one or more parent signals.
+ * When any parent signal aborts, the returned controller also aborts.
+ *
+ * Useful for creating child operations that should be cancelled when
+ * either the parent operation or their own timeout/condition triggers.
+ *
+ * @param signals - Parent signals to link to (undefined signals are ignored)
+ * @returns A new AbortController linked to all provided signals
+ *
+ * @example
+ * ```ts
+ * // Link to user's abort signal and add a timeout
+ * const linked = createLinkedController(userSignal, timeoutSignal);
+ * await fetch(url, { signal: linked.signal });
+ * ```
+ */
+export function createLinkedController(...signals: (AbortSignal | undefined)[]): AbortController {
+	const controller = new AbortController();
+
+	for (const signal of signals) {
+		if (!signal) continue;
+
+		// If already aborted, abort immediately
+		if (signal.aborted) {
+			controller.abort(signal.reason);
+			return controller;
+		}
+
+		// Link to parent signal
+		signal.addEventListener('abort', () => controller.abort(signal.reason), { once: true });
+	}
+
+	return controller;
+}
+
+/**
+ * Creates an AbortSignal that times out after the specified duration.
+ *
+ * @param ms - Timeout duration in milliseconds
+ * @returns AbortSignal that will abort after the timeout
+ *
+ * @example
+ * ```ts
+ * const signal = createTimeoutSignal(5000); // 5 second timeout
+ * await fetch(url, { signal });
+ * ```
+ */
+export function createTimeoutSignal(ms: number): AbortSignal {
+	return AbortSignal.timeout(ms);
+}
+
+/**
+ * Wraps a promise to reject if the signal is aborted.
+ * Useful for making non-abortable promises respect an AbortSignal.
+ *
+ * @param promise - Promise to wrap
+ * @param signal - AbortSignal to respect
+ * @returns Promise that rejects with AbortError if signal aborts
+ *
+ * @example
+ * ```ts
+ * // Make a non-abortable operation respect abort signal
+ * const result = await withAbortSignal(
+ *   someNonAbortableOperation(),
+ *   signal
+ * );
+ * ```
+ */
+export async function withAbortSignal<T>(promise: Promise<T>, signal?: AbortSignal): Promise<T> {
+	if (!signal) return promise;
+
+	throwIfAborted(signal);
+
+	return new Promise<T>((resolve, reject) => {
+		const abortHandler = () => {
+			reject(new DOMException('Operation was aborted', 'AbortError'));
+		};
+
+		signal.addEventListener('abort', abortHandler, { once: true });
+
+		promise
+			.then((value) => {
+				signal.removeEventListener('abort', abortHandler);
+				resolve(value);
+			})
+			.catch((error) => {
+				signal.removeEventListener('abort', abortHandler);
+				reject(error);
+			});
+	});
+}

tools/server/webui/src/lib/utils/api-fetch.ts

@@ -0,0 +1,155 @@
+import { base } from '$app/paths';
+import { getJsonHeaders, getAuthHeaders } from './api-headers';
+
+/**
+ * API Fetch Utilities
+ *
+ * Provides common fetch patterns used across services:
+ * - Automatic JSON headers
+ * - Error handling with proper error messages
+ * - Base path resolution
+ */
+
+export interface ApiFetchOptions extends Omit<RequestInit, 'headers'> {
+	/**
+	 * Use auth-only headers (no Content-Type).
+	 * Default: false (uses JSON headers with Content-Type: application/json)
+	 */
+	authOnly?: boolean;
+	/**
+	 * Additional headers to merge with default headers.
+	 */
+	headers?: Record<string, string>;
+}
+
+/**
+ * Fetch JSON data from an API endpoint with standard headers and error handling.
+ *
+ * @param path - API path (will be prefixed with base path)
+ * @param options - Fetch options with additional authOnly flag
+ * @returns Parsed JSON response
+ * @throws Error with formatted message on failure
+ *
+ * @example
+ * ```typescript
+ * // GET request
+ * const models = await apiFetch<ApiModelListResponse>('/v1/models');
+ *
+ * // POST request
+ * const result = await apiFetch<ApiResponse>('/models/load', {
+ *   method: 'POST',
+ *   body: JSON.stringify({ model: 'gpt-4' })
+ * });
+ * ```
+ */
+export async function apiFetch<T>(path: string, options: ApiFetchOptions = {}): Promise<T> {
+	const { authOnly = false, headers: customHeaders, ...fetchOptions } = options;
+
+	const baseHeaders = authOnly ? getAuthHeaders() : getJsonHeaders();
+	const headers = { ...baseHeaders, ...customHeaders };
+
+	const url =
+		path.startsWith('http://') || path.startsWith('https://') ? path : `${base}${path}`;
+
+	const response = await fetch(url, {
+		...fetchOptions,
+		headers
+	});
+
+	if (!response.ok) {
+		const errorMessage = await parseErrorMessage(response);
+		throw new Error(errorMessage);
+	}
+
+	return response.json() as Promise<T>;
+}
+
+/**
+ * Fetch with URL constructed from base URL and query parameters.
+ *
+ * @param basePath - Base API path
+ * @param params - Query parameters to append
+ * @param options - Fetch options
+ * @returns Parsed JSON response
+ *
+ * @example
+ * ```typescript
+ * const props = await apiFetchWithParams<ApiProps>('./props', {
+ *   model: 'gpt-4',
+ *   autoload: 'false'
+ * });
+ * ```
+ */
+export async function apiFetchWithParams<T>(
+	basePath: string,
+	params: Record<string, string>,
+	options: ApiFetchOptions = {}
+): Promise<T> {
+	const url = new URL(basePath, window.location.href);
+
+	for (const [key, value] of Object.entries(params)) {
+		if (value !== undefined && value !== null) {
+			url.searchParams.set(key, value);
+		}
+	}
+
+	const { authOnly = false, headers: customHeaders, ...fetchOptions } = options;
+
+	const baseHeaders = authOnly ? getAuthHeaders() : getJsonHeaders();
+	const headers = { ...baseHeaders, ...customHeaders };
+
+	const response = await fetch(url.toString(), {
+		...fetchOptions,
+		headers
+	});
+
+	if (!response.ok) {
+		const errorMessage = await parseErrorMessage(response);
+		throw new Error(errorMessage);
+	}
+
+	return response.json() as Promise<T>;
+}
+
+/**
+ * POST JSON data to an API endpoint.
+ *
+ * @param path - API path
+ * @param body - Request body (will be JSON stringified)
+ * @param options - Additional fetch options
+ * @returns Parsed JSON response
+ */
+export async function apiPost<T, B = unknown>(
+	path: string,
+	body: B,
+	options: ApiFetchOptions = {}
+): Promise<T> {
+	return apiFetch<T>(path, {
+		method: 'POST',
+		body: JSON.stringify(body),
+		...options
+	});
+}
+
+/**
+ * Parse error message from a failed response.
+ * Tries to extract error message from JSON body, falls back to status text.
+ */
+async function parseErrorMessage(response: Response): Promise<string> {
+	try {
+		const errorData = await response.json();
+		if (errorData?.error?.message) {
+			return errorData.error.message;
+		}
+		if (errorData?.error && typeof errorData.error === 'string') {
+			return errorData.error;
+		}
+		if (errorData?.message) {
+			return errorData.message;
+		}
+	} catch {
+		// JSON parsing failed, use status text
+	}
+
+	return `Request failed: ${response.status} ${response.statusText}`;
+}

tools/server/webui/src/lib/utils/branching.ts

@@ -15,6 +15,8 @@
  *        └── message 5 (assistant)
  */
 
+import { MessageRole } from '$lib/enums/chat';
+
 /**
  * Filters messages to get the conversation path from root to a specific leaf node.
  * If the leafNodeId doesn't exist, returns the path with the latest timestamp.
@@ -65,8 +67,13 @@ export function filterByLeafNodeId(
 		currentNode = nodeMap.get(currentNode.parent);
 	}
 
-	// Sort by timestamp to get chronological order (root to leaf)
-	result.sort((a, b) => a.timestamp - b.timestamp);
+	// Sort: system messages first, then by timestamp
+	result.sort((a, b) => {
+		if (a.role === MessageRole.SYSTEM && b.role !== MessageRole.SYSTEM) return -1;
+		if (a.role !== MessageRole.SYSTEM && b.role === MessageRole.SYSTEM) return 1;
+
+		return a.timestamp - b.timestamp;
+	});
 	return result;
 }
 

tools/server/webui/src/lib/utils/browser-only.ts

@@ -23,7 +23,7 @@ export {
 } from './pdf-processing';
 
 // File conversion utilities (depends on pdf-processing)
-export { parseFilesToMessageExtras, type FileProcessingResult } from './convert-files-to-extra';
+export { parseFilesToMessageExtras } from './convert-files-to-extra';
 
 // File upload processing utilities (depends on pdf-processing, svg-to-png, webp-to-png)
 export { processFilesToChatUploaded } from './process-uploaded-files';

tools/server/webui/src/lib/utils/cache-ttl.ts

@@ -0,0 +1,293 @@
+const DEFAULT_CACHE_TTL_MS = 5 * 60 * 1000;
+const DEFAULT_CACHE_MAX_ENTRIES = 100;
+
+/**
+ * TTL Cache - Time-To-Live cache implementation for memory optimization
+ *
+ * Provides automatic expiration of cached entries to prevent memory bloat
+ * in long-running sessions.
+ *
+ * @example
+ * ```ts
+ * const cache = new TTLCache<string, ApiData>({ ttlMs: 5 * 60 * 1000 }); // 5 minutes
+ * cache.set('key', data);
+ * const value = cache.get('key'); // null if expired
+ * ```
+ */
+
+export interface TTLCacheOptions {
+	/** Time-to-live in milliseconds. Default: 5 minutes */
+	ttlMs?: number;
+	/** Maximum number of entries. Oldest entries are evicted when exceeded. Default: 100 */
+	maxEntries?: number;
+	/** Callback when an entry expires or is evicted */
+	onEvict?: (key: string, value: unknown) => void;
+}
+
+interface CacheEntry<T> {
+	value: T;
+	expiresAt: number;
+	lastAccessed: number;
+}
+
+export class TTLCache<K extends string, V> {
+	private cache = new Map<K, CacheEntry<V>>();
+	private readonly ttlMs: number;
+	private readonly maxEntries: number;
+	private readonly onEvict?: (key: string, value: unknown) => void;
+
+	constructor(options: TTLCacheOptions = {}) {
+		this.ttlMs = options.ttlMs ?? DEFAULT_CACHE_TTL_MS;
+		this.maxEntries = options.maxEntries ?? DEFAULT_CACHE_MAX_ENTRIES;
+		this.onEvict = options.onEvict;
+	}
+
+	/**
+	 * Get a value from cache. Returns null if expired or not found.
+	 */
+	get(key: K): V | null {
+		const entry = this.cache.get(key);
+		if (!entry) return null;
+
+		if (Date.now() > entry.expiresAt) {
+			this.delete(key);
+			return null;
+		}
+
+		// Update last accessed time for LRU-like behavior
+		entry.lastAccessed = Date.now();
+		return entry.value;
+	}
+
+	/**
+	 * Set a value in cache with TTL.
+	 */
+	set(key: K, value: V, customTtlMs?: number): void {
+		// Evict oldest entries if at capacity
+		if (this.cache.size >= this.maxEntries && !this.cache.has(key)) {
+			this.evictOldest();
+		}
+
+		const ttl = customTtlMs ?? this.ttlMs;
+		const now = Date.now();
+
+		this.cache.set(key, {
+			value,
+			expiresAt: now + ttl,
+			lastAccessed: now
+		});
+	}
+
+	/**
+	 * Check if key exists and is not expired.
+	 */
+	has(key: K): boolean {
+		const entry = this.cache.get(key);
+		if (!entry) return false;
+
+		if (Date.now() > entry.expiresAt) {
+			this.delete(key);
+			return false;
+		}
+
+		return true;
+	}
+
+	/**
+	 * Delete a specific key from cache.
+	 */
+	delete(key: K): boolean {
+		const entry = this.cache.get(key);
+		if (entry && this.onEvict) {
+			this.onEvict(key, entry.value);
+		}
+		return this.cache.delete(key);
+	}
+
+	/**
+	 * Clear all entries from cache.
+	 */
+	clear(): void {
+		if (this.onEvict) {
+			for (const [key, entry] of this.cache) {
+				this.onEvict(key, entry.value);
+			}
+		}
+		this.cache.clear();
+	}
+
+	/**
+	 * Get the number of entries (including potentially expired ones).
+	 */
+	get size(): number {
+		return this.cache.size;
+	}
+
+	/**
+	 * Remove all expired entries from cache.
+	 * Call periodically for proactive cleanup.
+	 */
+	prune(): number {
+		const now = Date.now();
+		let pruned = 0;
+
+		for (const [key, entry] of this.cache) {
+			if (now > entry.expiresAt) {
+				this.delete(key);
+				pruned++;
+			}
+		}
+
+		return pruned;
+	}
+
+	/**
+	 * Get all valid (non-expired) keys.
+	 */
+	keys(): K[] {
+		const now = Date.now();
+		const validKeys: K[] = [];
+
+		for (const [key, entry] of this.cache) {
+			if (now <= entry.expiresAt) {
+				validKeys.push(key);
+			}
+		}
+
+		return validKeys;
+	}
+
+	/**
+	 * Evict the oldest (least recently accessed) entry.
+	 */
+	private evictOldest(): void {
+		let oldestKey: K | null = null;
+		let oldestTime = Infinity;
+
+		for (const [key, entry] of this.cache) {
+			if (entry.lastAccessed < oldestTime) {
+				oldestTime = entry.lastAccessed;
+				oldestKey = key;
+			}
+		}
+
+		if (oldestKey !== null) {
+			this.delete(oldestKey);
+		}
+	}
+
+	/**
+	 * Refresh TTL for an existing entry without changing the value.
+	 */
+	touch(key: K): boolean {
+		const entry = this.cache.get(key);
+		if (!entry) return false;
+
+		const now = Date.now();
+		if (now > entry.expiresAt) {
+			this.delete(key);
+			return false;
+		}
+
+		entry.expiresAt = now + this.ttlMs;
+		entry.lastAccessed = now;
+		return true;
+	}
+}
+
+/**
+ * Reactive TTL Map for Svelte stores
+ * Wraps SvelteMap with TTL functionality
+ */
+export class ReactiveTTLMap<K extends string, V> {
+	private entries = $state<Map<K, CacheEntry<V>>>(new Map());
+	private readonly ttlMs: number;
+	private readonly maxEntries: number;
+
+	constructor(options: TTLCacheOptions = {}) {
+		this.ttlMs = options.ttlMs ?? DEFAULT_CACHE_TTL_MS;
+		this.maxEntries = options.maxEntries ?? DEFAULT_CACHE_MAX_ENTRIES;
+	}
+
+	get(key: K): V | null {
+		const entry = this.entries.get(key);
+		if (!entry) return null;
+
+		if (Date.now() > entry.expiresAt) {
+			this.entries.delete(key);
+			return null;
+		}
+
+		entry.lastAccessed = Date.now();
+		return entry.value;
+	}
+
+	set(key: K, value: V, customTtlMs?: number): void {
+		if (this.entries.size >= this.maxEntries && !this.entries.has(key)) {
+			this.evictOldest();
+		}
+
+		const ttl = customTtlMs ?? this.ttlMs;
+		const now = Date.now();
+
+		this.entries.set(key, {
+			value,
+			expiresAt: now + ttl,
+			lastAccessed: now
+		});
+	}
+
+	has(key: K): boolean {
+		const entry = this.entries.get(key);
+		if (!entry) return false;
+
+		if (Date.now() > entry.expiresAt) {
+			this.entries.delete(key);
+			return false;
+		}
+
+		return true;
+	}
+
+	delete(key: K): boolean {
+		return this.entries.delete(key);
+	}
+
+	clear(): void {
+		this.entries.clear();
+	}
+
+	get size(): number {
+		return this.entries.size;
+	}
+
+	prune(): number {
+		const now = Date.now();
+		let pruned = 0;
+
+		for (const [key, entry] of this.entries) {
+			if (now > entry.expiresAt) {
+				this.entries.delete(key);
+				pruned++;
+			}
+		}
+
+		return pruned;
+	}
+
+	private evictOldest(): void {
+		let oldestKey: K | null = null;
+		let oldestTime = Infinity;
+
+		for (const [key, entry] of this.entries) {
+			if (entry.lastAccessed < oldestTime) {
+				oldestTime = entry.lastAccessed;
+				oldestKey = key;
+			}
+		}
+
+		if (oldestKey !== null) {
+			this.entries.delete(oldestKey);
+		}
+	}
+}

tools/server/webui/src/lib/utils/code.ts

@@ -0,0 +1,85 @@
+import hljs from 'highlight.js';
+import {
+	NEWLINE,
+	DEFAULT_LANGUAGE,
+	LANG_PATTERN,
+	AMPERSAND_REGEX,
+	LT_REGEX,
+	GT_REGEX,
+	FENCE_PATTERN
+} from '$lib/constants/code';
+
+export interface IncompleteCodeBlock {
+	language: string;
+	code: string;
+	openingIndex: number;
+}
+
+/**
+ * Highlights code using highlight.js
+ * @param code - The code to highlight
+ * @param language - The programming language
+ * @returns HTML string with syntax highlighting
+ */
+export function highlightCode(code: string, language: string): string {
+	if (!code) return '';
+
+	try {
+		const lang = language.toLowerCase();
+		const isSupported = hljs.getLanguage(lang);
+
+		if (isSupported) {
+			return hljs.highlight(code, { language: lang }).value;
+		} else {
+			return hljs.highlightAuto(code).value;
+		}
+	} catch {
+		// Fallback to escaped plain text
+		return code
+			.replace(AMPERSAND_REGEX, '&')
+			.replace(LT_REGEX, '<')
+			.replace(GT_REGEX, '>');
+	}
+}
+
+/**
+ * Detects if markdown ends with an incomplete code block (opened but not closed).
+ * Returns the code block info if found, null otherwise.
+ * @param markdown - The raw markdown string to check
+ * @returns IncompleteCodeBlock info or null
+ */
+export function detectIncompleteCodeBlock(markdown: string): IncompleteCodeBlock | null {
+	// Count all code fences in the markdown
+	// A code block is incomplete if there's an odd number of ``` fences
+	const fencePattern = new RegExp(FENCE_PATTERN.source, FENCE_PATTERN.flags);
+	const fences: number[] = [];
+	let fenceMatch;
+
+	while ((fenceMatch = fencePattern.exec(markdown)) !== null) {
+		// Store the position after the ```
+		const pos = fenceMatch[0].startsWith(NEWLINE) ? fenceMatch.index + 1 : fenceMatch.index;
+		fences.push(pos);
+	}
+
+	// If even number of fences (including 0), all code blocks are closed
+	if (fences.length % 2 === 0) {
+		return null;
+	}
+
+	// Odd number means last code block is incomplete
+	// The last fence is the opening of the incomplete block
+	const openingIndex = fences[fences.length - 1];
+	const afterOpening = markdown.slice(openingIndex + 3);
+
+	// Extract language and code content
+	const langMatch = afterOpening.match(LANG_PATTERN);
+	const language = langMatch?.[1] || DEFAULT_LANGUAGE;
+	const codeStartIndex = openingIndex + 3 + (langMatch?.[0]?.length ?? 0);
+	const code = markdown.slice(codeStartIndex);
+
+	return {
+		language,
+		code,
+		openingIndex
+	};
+}

tools/server/webui/src/lib/utils/data-url.ts

@@ -0,0 +1,10 @@
+/**
+ * Creates a base64 data URL from MIME type and base64-encoded data.
+ *
+ * @param mimeType - The MIME type (e.g., 'image/png', 'audio/mp3')
+ * @param base64Data - The base64-encoded data
+ * @returns A data URL string in format 'data:{mimeType};base64,{data}'
+ */
+export function createBase64DataUrl(mimeType: string, base64Data: string): string {
+	return `data:${mimeType};base64,${base64Data}`;
+}

tools/server/webui/src/lib/utils/debounce.ts

@@ -0,0 +1,22 @@
+/**
+ * @param fn - The function to debounce
+ * @param delay - The delay in milliseconds
+ * @returns A debounced version of the function
+ */
+export function debounce<T extends (...args: Parameters<T>) => void>(
+	fn: T,
+	delay: number
+): (...args: Parameters<T>) => void {
+	let timeoutId: ReturnType<typeof setTimeout> | null = null;
+
+	return (...args: Parameters<T>) => {
+		if (timeoutId) {
+			clearTimeout(timeoutId);
+		}
+
+		timeoutId = setTimeout(() => {
+			fn(...args);
+			timeoutId = null;
+		}, delay);
+	};
+}

tools/server/webui/src/lib/utils/image-error-fallback.ts

@@ -0,0 +1,10 @@
+/**
+ * Simplified HTML fallback for external images that fail to load.
+ * Displays a centered message with a link to open the image in a new tab.
+ */
+export function getImageErrorFallbackHtml(src: string): string {
+	return `<div class="image-error-content">
+		<span>Image cannot be displayed</span>
+		<a href="${src}" target="_blank" rel="noopener noreferrer">(open link)</a>
+	</div>`;
+}

tools/server/webui/src/lib/utils/index.ts

@@ -9,6 +9,7 @@
 
 // API utilities
 export { getAuthHeaders, getJsonHeaders } from './api-headers';
+export { apiFetch, apiFetchWithParams, apiPost, type ApiFetchOptions } from './api-fetch';
 export { validateApiKey } from './api-key-validation';
 
 // Attachment utilities
@@ -75,8 +76,7 @@ export { maskInlineLaTeX, preprocessLaTeX } from './latex-protection';
 export {
 	isFileTypeSupportedByModel,
 	filterFilesByModalities,
-	generateModalityErrorMessage,
-	type ModalityCapabilities
+	generateModalityErrorMessage
 } from './modality-file-validation';
 
 // Model name utilities

tools/server/webui/src/lib/utils/modality-file-validation.ts

@@ -5,12 +5,7 @@
 
 import { getFileTypeCategory } from '$lib/utils';
 import { FileTypeCategory } from '$lib/enums';
-
-/** Modality capabilities for file validation */
-export interface ModalityCapabilities {
-	hasVision: boolean;
-	hasAudio: boolean;
-}
+import type { ModalityCapabilities } from '$lib/types/models';
 
 /**
  * Check if a file type is supported by the given modalities

tools/server/webui/src/lib/utils/text-files.ts

@@ -3,10 +3,8 @@
  * Handles text file detection, reading, and validation
  */
 
-import {
-	DEFAULT_BINARY_DETECTION_OPTIONS,
-	type BinaryDetectionOptions
-} from '$lib/constants/binary-detection';
+import { DEFAULT_BINARY_DETECTION_OPTIONS } from '$lib/constants/binary-detection';
+import type { BinaryDetectionOptions } from '$lib/constants/binary-detection';
 import { FileExtensionText } from '$lib/enums';
 
 /**