diff --git a/src/lib/components/chat/FileNav.svelte b/src/lib/components/chat/FileNav.svelte
index 5b34f7dce..46df84b48 100644
--- a/src/lib/components/chat/FileNav.svelte
+++ b/src/lib/components/chat/FileNav.svelte
@@ -119,6 +119,8 @@
 	$: isMarkdown = MD_EXTS.has(getFileExt(selectedFile));
 	$: isCsv = CSV_EXTS.has(getFileExt(selectedFile));
 	$: isHtml = HTML_EXTS.has(getFileExt(selectedFile));
+	$: isJson = ['json', 'jsonc', 'jsonl', 'json5'].includes(getFileExt(selectedFile));
+	$: isSvg = getFileExt(selectedFile) === 'svg';
 	$: isCode = isCodeFile(selectedFile);
 	$: isOfficeFile = OFFICE_EXTS.has(getFileExt(selectedFile));
 	$: isTextFile =
@@ -182,7 +184,7 @@
 	}
 
 	// ── Helpers ──────────────────────────────────────────────────────────
-	const IMAGE_EXTS = new Set(['jpg', 'jpeg', 'png', 'gif', 'webp', 'svg', 'bmp', 'ico', 'avif']);
+	const IMAGE_EXTS = new Set(['jpg', 'jpeg', 'png', 'gif', 'webp', 'bmp', 'ico', 'avif']);
 	const VIDEO_EXTS = new Set(['mp4', 'webm', 'mov', 'ogv', 'avi', 'mkv']);
 	const AUDIO_EXTS = new Set(['mp3', 'wav', 'ogg', 'oga', 'flac', 'm4a', 'aac', 'wma', 'opus']);
 	const isImage = (path: string) => IMAGE_EXTS.has(path.split('.').pop()?.toLowerCase() ?? '');
@@ -634,7 +636,7 @@
 					</button>
 				</Tooltip>
 			{/if}
-			{#if (isMarkdown || isCsv || isHtml || isCode) && fileContent !== null && !editing}
+			{#if (isMarkdown || isCsv || isHtml || isCode || isJson || isSvg) && fileContent !== null && !editing}
 				<Tooltip content={showRaw ? $i18n.t('Preview') : $i18n.t('Source')}>
 					<button
 						class="shrink-0 p-1 rounded hover:bg-gray-100 dark:hover:bg-gray-800 transition text-gray-400 dark:text-gray-500 hover:text-gray-600 dark:hover:text-gray-400"
diff --git a/src/lib/components/chat/FileNav/FilePreview.svelte b/src/lib/components/chat/FileNav/FilePreview.svelte
index 6878b2980..a2b212527 100644
--- a/src/lib/components/chat/FileNav/FilePreview.svelte
+++ b/src/lib/components/chat/FileNav/FilePreview.svelte
@@ -7,6 +7,7 @@
 	import { isCodeFile, highlightCode } from '$lib/utils/codeHighlight';
 	import Spinner from '../../common/Spinner.svelte';
 	import PDFViewer from '../../common/PDFViewer.svelte';
+	import JsonTreeView from './JsonTreeView.svelte';
 
 	let pdfViewerRef: PDFViewer;
 
@@ -72,11 +73,14 @@
 	const MD_EXTS = new Set(['md', 'markdown', 'mdx']);
 	const CSV_EXTS = new Set(['csv', 'tsv']);
 	const HTML_EXTS = new Set(['html', 'htm']);
+	const JSON_EXTS = new Set(['json', 'jsonc', 'jsonl', 'json5']);
 	const getExt = (path: string | null) => path?.split('.').pop()?.toLowerCase() ?? '';
 
 	$: isMarkdown = MD_EXTS.has(getExt(selectedFile));
 	$: isCsv = CSV_EXTS.has(getExt(selectedFile));
 	$: isHtml = HTML_EXTS.has(getExt(selectedFile));
+	$: isJson = JSON_EXTS.has(getExt(selectedFile));
+	$: isSvg = getExt(selectedFile) === 'svg';
 	$: isCode = isCodeFile(selectedFile);
 	$: csvDelimiter = getExt(selectedFile) === 'tsv' ? '\t' : ',';
 	$: renderedHtml =
@@ -131,10 +135,20 @@
 	let highlightedHtml: string | null = null;
 	let highlightingFile: string | null = null; // track which file we're highlighting
 
-	$: if (isCode && fileContent !== null && selectedFile) {
+	$: if ((isCode || isSvg) && fileContent !== null && selectedFile) {
 		const currentFile = selectedFile;
 		highlightingFile = currentFile;
-		highlightCode(fileContent, selectedFile)
+		const lang = isSvg ? 'xml' : undefined;
+		(lang
+			? import('shiki').then(({ codeToHtml }) =>
+					codeToHtml(fileContent!, {
+						lang: 'xml',
+						themes: { light: 'github-light', dark: 'github-dark' },
+						defaultColor: 'light'
+					})
+				)
+			: highlightCode(fileContent!, selectedFile!)
+		)
 			.then((html) => {
 				if (highlightingFile === currentFile) highlightedHtml = html;
 			})
@@ -145,6 +159,23 @@
 		highlightedHtml = null;
 	}
 
+	// ── JSON parsing ────────────────────────────────────────────────────
+	let parsedJson: unknown = undefined;
+	let jsonError: string | null = null;
+
+	$: if (isJson && fileContent !== null) {
+		try {
+			parsedJson = JSON.parse(fileContent);
+			jsonError = null;
+		} catch (e) {
+			parsedJson = undefined;
+			jsonError = e instanceof Error ? e.message : 'Invalid JSON';
+		}
+	} else {
+		parsedJson = undefined;
+		jsonError = null;
+	}
+
 	export let showRaw = false;
 	$: selectedFile, (showRaw = false); // reset to preview mode when switching files
 
@@ -321,7 +352,20 @@
 					</tbody>
 				</table>
 			</div>
-		{:else if isCode && highlightedHtml && !showRaw}
+		{:else if isJson && !showRaw && parsedJson !== undefined}
+			<div class="overflow-auto h-full">
+				<JsonTreeView data={parsedJson} />
+			</div>
+		{:else if isJson && !showRaw && jsonError}
+			<div class="p-3 text-xs">
+				<div class="text-red-500 mb-2">JSON parse error: {jsonError}</div>
+				<pre class="text-xs font-mono text-gray-800 dark:text-gray-200 whitespace-pre-wrap break-all leading-relaxed">{fileContent}</pre>
+			</div>
+		{:else if isSvg && !showRaw && fileContent}
+			<div class="svg-preview w-full h-full flex items-center justify-center overflow-auto p-3">
+				{@html DOMPurify.sanitize(fileContent, { USE_PROFILES: { svg: true, svgFilters: true }, ADD_TAGS: ['use'] })}
+			</div>
+		{:else if (isCode || isSvg) && highlightedHtml && !showRaw}
 			<div class="shiki-preview overflow-auto h-full text-xs">
 				{@html highlightedHtml}
 			</div>
diff --git a/src/lib/components/chat/FileNav/JsonTreeView.svelte b/src/lib/components/chat/FileNav/JsonTreeView.svelte
new file mode 100644
index 000000000..a76f4f06e
--- /dev/null
+++ b/src/lib/components/chat/FileNav/JsonTreeView.svelte
@@ -0,0 +1,147 @@
+<script lang="ts">
+	export let data: unknown;
+	export let key: string | null = null;
+	export let root = true;
+	export let expandDepth = 2;
+
+	let depth = 0;
+	export { depth };
+
+	$: expanded = depth < expandDepth;
+
+	const toggle = () => {
+		expanded = !expanded;
+	};
+
+	$: type = Array.isArray(data) ? 'array' : data === null ? 'null' : typeof data;
+	$: isExpandable = type === 'object' || type === 'array';
+	$: entries = isExpandable && data !== null ? Object.entries(data as Record<string, unknown>) : [];
+	$: bracket = type === 'array' ? ['[', ']'] : ['{', '}'];
+	$: preview =
+		type === 'array'
+			? `[${(data as unknown[]).length}]`
+			: type === 'object'
+				? `{${entries.length}}`
+				: '';
+</script>
+
+{#if isExpandable}
+	<div class="json-node" class:json-root={root}>
+		<!-- svelte-ignore a11y-click-events-have-key-events -->
+		<!-- svelte-ignore a11y-no-static-element-interactions -->
+		<span class="json-toggle" on:click={toggle}>
+			<span class="json-arrow" class:json-expanded={expanded}>▶</span>
+			{#if key !== null}<span class="json-key">{key}</span><span class="json-colon">: </span>{/if}
+			{#if !expanded}<span class="json-preview">{bracket[0]} {preview} {bracket[1]}</span>{/if}
+			{#if expanded}<span class="json-bracket">{bracket[0]}</span>{/if}
+		</span>
+		{#if expanded}
+			<div class="json-children">
+				{#each entries as [k, v], i}
+					<div class="json-entry">
+						<svelte:self data={v} key={type === 'array' ? null : k} root={false} depth={depth + 1} {expandDepth} />
+						{#if i < entries.length - 1}<span class="json-comma">,</span>{/if}
+					</div>
+				{/each}
+			</div>
+			<span class="json-bracket">{bracket[1]}</span>
+		{/if}
+	</div>
+{:else}
+	<span class="json-leaf">
+		{#if key !== null}<span class="json-key">{key}</span><span class="json-colon">: </span>{/if}
+		{#if type === 'string'}
+			<span class="json-string">"{data}"</span>
+		{:else if type === 'number'}
+			<span class="json-number">{data}</span>
+		{:else if type === 'boolean'}
+			<span class="json-boolean">{data}</span>
+		{:else if type === 'null'}
+			<span class="json-null">null</span>
+		{:else}
+			<span>{String(data)}</span>
+		{/if}
+	</span>
+{/if}
+
+<style>
+	.json-root {
+		font-family: ui-monospace, SFMono-Regular, 'SF Mono', Menlo, Consolas, monospace;
+		font-size: 0.75rem;
+		line-height: 1.6;
+		padding: 0.75rem 1rem;
+	}
+	.json-node {
+		/* keep structure visible */
+	}
+	.json-toggle {
+		cursor: pointer;
+		user-select: none;
+	}
+	.json-toggle:hover {
+		opacity: 0.7;
+	}
+	.json-arrow {
+		display: inline-block;
+		width: 1em;
+		font-size: 0.55em;
+		transition: transform 0.15s ease;
+		color: #9ca3af;
+		vertical-align: middle;
+	}
+	.json-expanded {
+		transform: rotate(90deg);
+	}
+	.json-children {
+		padding-left: 1.25em;
+		border-left: 1px solid rgba(128, 128, 128, 0.15);
+		margin-left: 0.35em;
+	}
+	.json-entry {
+		/* one entry per line */
+	}
+	.json-key {
+		color: #0550ae;
+	}
+	:global(.dark) .json-key {
+		color: #79c0ff;
+	}
+	.json-colon {
+		color: #6b7280;
+	}
+	.json-string {
+		color: #0a3069;
+	}
+	:global(.dark) .json-string {
+		color: #a5d6ff;
+	}
+	.json-number {
+		color: #0550ae;
+	}
+	:global(.dark) .json-number {
+		color: #79c0ff;
+	}
+	.json-boolean {
+		color: #cf222e;
+	}
+	:global(.dark) .json-boolean {
+		color: #ff7b72;
+	}
+	.json-null {
+		color: #6b7280;
+		font-style: italic;
+	}
+	.json-bracket {
+		color: #6b7280;
+	}
+	.json-comma {
+		color: #6b7280;
+	}
+	.json-preview {
+		color: #9ca3af;
+		font-size: 0.85em;
+	}
+	:global(.dark) .json-preview {
+		color: #6b7280;
+	}
+</style>