ios: add Agent attachments and shared transcript fade

ios/Tests/Fixtures/agent_server.py

@@ -5,6 +5,10 @@ Run with Python + aiohttp, then xcodebuild test -scheme SybilAgentUI.
 import asyncio
 import datetime
 import json
+import hashlib
+import unicodedata
+import uuid
+from urllib.parse import quote
 from aiohttp import web
 
 sockets = set()
@@ -16,6 +20,21 @@ busy = False
 attempts = {}
 log = []
 reply_tasks = set()
+attachments = {}
+uploads = {}
+attachment_capability = True
+next_upload_error = None
+blocked_proxy = False
+transcript_comparison = False
+CAPABILITY = dict(version=1, maxCount=8, maxTotalBytes=33554432, maxImageBytes=6291456,
+                  maxFileBytes=8388608, imageMimeTypes=['image/png', 'image/jpeg', 'image/gif', 'image/webp'],
+                  maxImagePixels=50000000, maxImageDimension=16384, quotaBytes=1073741824, usedBytes=0,
+                  remainingBytes=1073741824, maxConcurrentUploads=2, maxConcurrentDecodes=1)
+
+def attachment_error(status, code, message, **fields):
+    return web.json_response(dict(error=True, message=message, statusCode=status, code=code, **fields), status=status,
+                             headers={"Retry-After": "2"} if status == 429 else None)
+
 
 def stamp():
     return datetime.datetime.now(datetime.timezone.utc).isoformat(timespec='milliseconds').replace('+00:00', 'Z')
@@ -69,7 +88,7 @@ async def reply(content):
     await broadcast(dict(type='activity', conversationId='fixture-root', activity=activity()))
 
 async def route(request):
-    global read_cursor, cursor, busy
+    global read_cursor, cursor, busy, attachment_capability, next_upload_error, blocked_proxy, transcript_comparison
     path = request.path
     log.append(dict(method=request.method, path=path, query=dict(request.query)))
     if path == '/control':
@@ -80,8 +99,21 @@ async def route(request):
                 task.cancel()
             reply_tasks.clear()
             messages.clear(); requests.clear(); attempts.clear(); cursor = 0; read_cursor = 0; busy = False
+            attachment_capability = True; next_upload_error = None; blocked_proxy = False; transcript_comparison = False
             for i in range(body.get('count', 3)):
                 message(f'History message {i + 1}: local simulator fixture.')
+        elif action == 'transcript-comparison':
+            transcript_comparison = True
+        elif action == 'capability':
+            attachment_capability = body.get('enabled', True)
+        elif action == 'upload-error':
+            next_upload_error = body
+        elif action == 'blocked-proxy':
+            blocked_proxy = body.get('enabled', True)
+        elif action == 'attachment-history':
+            selected = [attachments[key]['descriptor'] for key in body['ids']]
+            row = message(body.get('content') or 'Attached: ' + ', '.join(a['filename'] for a in selected) + '.', 'user', info={'agentAttachments': selected})
+            await broadcast(dict(type='messages', **page([row])))
         elif action == 'reply':
             await emit(body.get('content', 'Late asynchronous fixture reply'))
         elif action == 'long-tool':
@@ -102,10 +134,13 @@ async def route(request):
         return web.json_response(dict(cursor=cursor, readCursor=read_cursor, messages=messages, requests=requests, log=log))
     if path == '/api/v1/auth/session':
         return web.json_response(dict(authenticated=True, mode='token'))
+    comparison = dict(id='fade-comparison', title='Transcript fade comparison', createdAt=stamp(), updatedAt=stamp())
     if path == '/api/v1/workspace-items':
-        return web.json_response(dict(items=[], hasMore=False))
+        return web.json_response(dict(items=[dict(comparison, type='chat')] if transcript_comparison else [], hasMore=False))
     if path == '/api/v1/chats':
-        return web.json_response(dict(chats=[]))
+        return web.json_response(dict(chats=[comparison] if transcript_comparison else []))
+    if path == '/api/v1/chats/fade-comparison' and transcript_comparison:
+        return web.json_response(dict(chat=dict(comparison, messages=messages)))
     if path == '/api/v1/searches':
         return web.json_response(dict(searches=[]))
     if path == '/api/v1/models':
@@ -115,8 +150,70 @@ async def route(request):
     if path.startswith('/api/v1/agent') and path != '/api/v1/agent/ws':
         if request.headers.get('Authorization') != 'Bearer fixture-token':
             return web.json_response(dict(error='Fixture token missing'), status=401)
+        if blocked_proxy:
+            return attachment_error(503, 'attachments_unavailable', 'Synthetic proxy requires safely authenticated Agent access.')
     if path == '/api/v1/agent':
-        return web.json_response(dict(id='fixture-root', title='Sybil Agent', type='persistent-agent', model='fixture', protocol='pi-room.v1', websocket='/v1/agent/ws', activity=activity()))
+        descriptor = dict(id='fixture-root', title='Sybil Agent', type='persistent-agent', model='fixture', protocol='pi-room.v1', websocket='/v1/agent/ws', activity=activity())
+        if attachment_capability:
+            descriptor['capabilities'] = {'attachments': CAPABILITY}
+        return web.json_response(descriptor)
+    if path == '/api/v1/agent/attachments' and request.method == 'POST':
+        if not attachment_capability:
+            return attachment_error(503, 'attachments_unavailable', 'Attachments are unavailable.')
+        if next_upload_error:
+            failure = next_upload_error; next_upload_error = None
+            return attachment_error(failure.get('status', 507), failure.get('code', 'attachment_quota_exceeded'),
+                                    'Synthetic attachment storage is full; contact the operator or retry later.', **({'quotaBytes': 1073741824, 'remainingBytes': 0, 'requiredBytes': 20000} if failure.get('status', 507) == 507 else {}))
+        reader = await request.multipart()
+        parts = {}
+        while part := await reader.next():
+            if part.name not in ('file', 'uploadId') or part.name in parts:
+                return attachment_error(400, 'invalid_upload', 'Exactly one file and uploadId are required.')
+            parts[part.name] = (part.filename, part.headers.get('Content-Type'), bytes(await part.read(decode=False)))
+        if set(parts) != {'file', 'uploadId'}:
+            return attachment_error(400, 'invalid_upload', 'Missing file or uploadId.')
+        try:
+            upload_id = str(uuid.UUID(parts['uploadId'][2].decode()))
+            filename = unicodedata.normalize('NFC', parts['file'][0])
+            assert filename and len(filename.encode()) <= 255 and filename not in ('.', '..')
+            assert not any(c in '/\\' or unicodedata.category(c) == 'Cc' for c in filename)
+        except (ValueError, AssertionError, TypeError):
+            return attachment_error(400, 'invalid_upload', 'Invalid upload ID or filename.')
+        _, mime, data = parts['file']
+        mime = (mime or 'application/octet-stream').lower()
+        if len(data) > CAPABILITY['maxFileBytes']:
+            return attachment_error(413, 'attachment_limit_exceeded', 'File exceeds the upload limit.')
+        digest = hashlib.sha256(data).hexdigest()
+        identity = (filename, mime, digest)
+        if upload_id in uploads:
+            old_identity, attachment_id = uploads[upload_id]
+            if old_identity != identity:
+                return attachment_error(409, 'idempotency_conflict', 'Upload ID already belongs to another original.')
+            return web.json_response({'attachment': attachments[attachment_id]['descriptor']})
+        kind = 'file'
+        if mime in CAPABILITY['imageMimeTypes']:
+            kind = 'image'  # Synthetic fixture images are generated by the test; runtime validates decoding.
+        elif mime.startswith('text/'):
+            try:
+                if '\0' not in data.decode('utf-8-sig'):
+                    kind = 'text'
+            except UnicodeDecodeError:
+                pass
+        attachment_id = 'fixture-' + str(uuid.uuid4())
+        descriptor = dict(id=attachment_id, kind=kind, filename=filename, mimeType=mime, sizeBytes=len(data), sha256=digest,
+                          workspacePath='/data/workspace/uploads/' + attachment_id + '/' + ('_' + filename[1:] if filename.startswith('.') else filename))
+        attachments[attachment_id] = dict(descriptor=descriptor, data=data)
+        uploads[upload_id] = (identity, attachment_id)
+        return web.json_response({'attachment': descriptor}, status=201)
+    if path.startswith('/api/v1/agent/attachments/') and path.endswith('/content'):
+        attachment_id = path.removeprefix('/api/v1/agent/attachments/').removesuffix('/content')
+        stored = attachments.get(attachment_id)
+        if stored is None:
+            return attachment_error(404, 'attachment_not_found', 'The original is unavailable.')
+        descriptor = stored['descriptor']
+        mime = descriptor['mimeType'] if descriptor['kind'] == 'image' else 'text/plain' if descriptor['kind'] == 'text' else 'application/octet-stream'
+        return web.Response(body=stored['data'], content_type=mime, headers={'Cache-Control': 'private, no-store',
+                            'Content-Disposition': 'attachment; filename="original"; filename*=UTF-8\'\'' + quote(descriptor['filename'], safe=''), 'X-Content-Type-Options': 'nosniff'})
     if path == '/api/v1/agent/read-state':
         if request.method == 'PUT':
             read_cursor = max(read_cursor, int((await request.json())['cursor']))
@@ -125,13 +222,29 @@ async def route(request):
         if request.method == 'POST':
             body = await request.json()
             key, content = body['requestId'], body['content']
+            refs = body.get('attachments', [])
+            ids = [ref.get('id') for ref in refs]
+            if refs and not attachment_capability:
+                return attachment_error(503, 'attachments_unavailable', 'Attachments are unavailable.')
+            if any(set(ref) != {'id'} for ref in refs) or len(ids) != len(set(ids)) or len(ids) > 8:
+                return attachment_error(400, 'invalid_attachment', 'Invalid ordered references.')
+            if any(key not in attachments for key in ids):
+                return attachment_error(404, 'attachment_not_found', 'The attachment does not exist.')
+            if not content.strip() and not ids:
+                return attachment_error(400, 'invalid_attachment', 'Enter a caption or attach files.')
+            if key in requests and (ids or requests[key].get('attachmentIds')) and requests[key].get('_payload') != [content, ids]:
+                return attachment_error(409, 'idempotency_conflict', 'Message identity is already bound to another payload.')
             attempts[key] = attempts.get(key, 0) + 1
             if content == 'retry fixture' and attempts[key] == 1:
                 return web.json_response(dict(error='Simulated uncertain admission; retry'), status=502)
             receipt = dict(id=len(requests) + 1, status='queued', messageId=f'inbound:sybil:{key}')
+            if ids:
+                receipt['attachmentIds'] = ids
             if key not in requests:
-                requests[key] = receipt
-                row = message(content, 'user', id=receipt['messageId'])
+                requests[key] = dict(receipt, _payload=[content, ids])
+                descriptors = [attachments[key]['descriptor'] for key in ids]
+                display = content if content.strip() else 'Attached: ' + ', '.join(a['filename'] for a in descriptors) + '.'
+                row = message(display, 'user', id=receipt['messageId'], info={'agentAttachments': descriptors} if ids else None)
                 busy = True
                 await broadcast(dict(type='messages', **page([row])))
                 await broadcast(dict(type='activity', conversationId='fixture-root', activity=activity()))
@@ -141,7 +254,7 @@ async def route(request):
             if content == 'echo wins fixture':
                 await asyncio.sleep(0.3)
                 return web.json_response(dict(error='Lost HTTP acknowledgement'), status=502)
-            return web.json_response(requests[key], status=202)
+            return web.json_response({k: v for k, v in requests[key].items() if k != '_payload'}, status=202)
         after = int(request.query.get('after', 0))
         rows = [m for m in messages if m['metadata']['entryId'] > after]
         limit = min(int(request.query.get('limit', 200)), 200)
@@ -151,6 +264,9 @@ async def route(request):
         if request.query:
             return web.Response(status=400)
         socket = web.WebSocketResponse(); await socket.prepare(request)
+        if blocked_proxy:
+            await socket.close(code=4503, message=b'attachments_unavailable')
+            return socket
         auth = await socket.receive_json(timeout=5)
         if auth.get('token') != 'fixture-token' or auth.get('type') != 'auth':
             await socket.close(code=4401); return socket
@@ -172,6 +288,6 @@ async def route(request):
 
 for i in range(3):
     message(f'History message {i + 1}: local simulator fixture.')
-app = web.Application()
+app = web.Application(client_max_size=8 * 1024 * 1024 + 64 * 1024)
 app.router.add_route('*', '/{path:.*}', route)
 web.run_app(app, host='127.0.0.1', port=8799)

ios/Tests/SybilUITests/AgentUITests.swift

@@ -1,5 +1,6 @@
 import XCTest
 import UIKit
+import Photos
 
 @MainActor
 final class AgentUITests: XCTestCase {
@@ -10,7 +11,9 @@ final class AgentUITests: XCTestCase {
         app.launchArguments = ["-sybil.ios.apiBaseURL", "http://127.0.0.1:8799/api", "-sybil.ios.adminToken", "fixture-token"]
         app.launch()
         openAgent()
+        try clearComposer()
     }
+    override func tearDown() async throws { app.terminate() }
     private func openAgent() {
         if !app.buttons["agent-sidebar"].waitForExistence(timeout: 2) || !app.buttons["agent-sidebar"].isHittable {
             XCTAssertTrue(app.buttons["Show sidebar"].waitForExistence(timeout: 15))
@@ -23,6 +26,16 @@ final class AgentUITests: XCTestCase {
     private var composer: XCUIElement {
         app.textFields["agent-composer"].exists ? app.textFields["agent-composer"] : app.textViews["agent-composer"]
     }
+    private func clearComposer() throws {
+        guard let existing = composer.value as? String, !existing.isEmpty, existing != "Enter Prompt" else { return }
+        composer.tap(); composer.press(forDuration: 1)
+        let selectAll = app.descendants(matching: .any).matching(NSPredicate(format: "label == %@", "Select All")).firstMatch
+        if selectAll.waitForExistence(timeout: 2) { selectAll.tap() }
+        else { composer.typeText(String(repeating: XCUIKeyboardKey.rightArrow.rawValue, count: existing.count)) }
+        composer.typeText(String(repeating: XCUIKeyboardKey.delete.rawValue, count: existing.count))
+        let value = composer.value as? String ?? ""
+        _ = try XCTUnwrap(value.isEmpty || value == "Enter Prompt" ? true : nil, "Clear the synthetic fixture caption before the next test")
+    }
     private func send(_ text: String) {
         composer.tap(); composer.typeText(text); app.buttons["agent-send"].tap()
     }
@@ -37,6 +50,171 @@ final class AgentUITests: XCTestCase {
         let (data, _) = try await URLSession.shared.data(for: request)
         return try XCTUnwrap(JSONSerialization.jsonObject(with: data) as? [String: Any])
     }
+    private func uploadOriginal(name: String, mime: String, bytes: Data) async throws -> [String: Any] {
+        let boundary = "Fixture-" + UUID().uuidString
+        let uploadID = UUID().uuidString
+        var body = Data("--\(boundary)\r\nContent-Disposition: form-data; name=\"uploadId\"\r\n\r\n\(uploadID)\r\n--\(boundary)\r\nContent-Disposition: form-data; name=\"file\"; filename=\"\(name)\"\r\nContent-Type: \(mime)\r\n\r\n".utf8)
+        body.append(bytes); body.append(Data("\r\n--\(boundary)--\r\n".utf8))
+        var request = URLRequest(url: URL(string: "http://127.0.0.1:8799/api/v1/agent/attachments")!)
+        request.httpMethod = "POST"; request.httpBody = body
+        request.setValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")
+        request.setValue("Bearer fixture-token", forHTTPHeaderField: "Authorization")
+        let (data, response) = try await URLSession.shared.data(for: request)
+        XCTAssertEqual((response as? HTTPURLResponse)?.statusCode, 201)
+        let json = try XCTUnwrap(JSONSerialization.jsonObject(with: data) as? [String: Any])
+        return try XCTUnwrap(json["attachment"] as? [String: Any])
+    }
+
+    func testAttachmentHistoryDownloadAndReload() async throws {
+        let original = Data("Synthetic original text. <script>plain text only</script>".utf8)
+        let file = try await uploadOriginal(name: "fixture-original.txt", mime: "text/plain", bytes: original)
+        let image = UIGraphicsImageRenderer(size: CGSize(width: 64, height: 48)).image { context in
+            UIColor.systemTeal.setFill(); context.fill(CGRect(x: 0, y: 0, width: 64, height: 48))
+        }
+        let photo = try await uploadOriginal(name: "fixture-image.png", mime: "image/png", bytes: try XCTUnwrap(image.pngData()))
+        let ids = [try XCTUnwrap(file["id"] as? String), try XCTUnwrap(photo["id"] as? String)]
+        try await control(["action": "attachment-history", "ids": ids, "content": "Synthetic attachments caption"])
+        XCTAssertTrue(app.staticTexts["Synthetic attachments caption"].waitForExistence(timeout: 8))
+        XCTAssertTrue(app.staticTexts["fixture-original.txt"].exists)
+        XCTAssertTrue(app.staticTexts["fixture-image.png"].exists)
+        let path = try XCTUnwrap(file["workspacePath"] as? String)
+        XCTAssertTrue(app.buttons["Copy workspace path: " + path].exists)
+        let download = app.buttons["agent-download"].firstMatch
+        if !download.isHittable { app.scrollViews.firstMatch.swipeDown() }
+        XCTAssertTrue(download.waitForExistence(timeout: 5)); download.tap()
+        XCTAssertTrue(app.buttons["Save or share original"].waitForExistence(timeout: 8))
+        XCTAssertTrue(app.staticTexts.containing(NSPredicate(format: "label CONTAINS %@", "<script>plain text only</script>")).firstMatch.exists)
+        capture("agent-attachment-original-and-preview")
+        try await control(["action": "long-tool"])
+        XCTAssertFalse(app.staticTexts["Local tool output"].exists)
+        app.terminate(); app.launch(); openAgent()
+        XCTAssertTrue(app.staticTexts["fixture-image.png"].waitForExistence(timeout: 8))
+        XCTAssertTrue(app.staticTexts["fixture-original.txt"].exists)
+        XCTAssertFalse(app.staticTexts["Local tool output"].exists)
+        capture("agent-attachment-reloaded")
+        // The real app's authenticated content request is recorded by the loopback fixture.
+        let state = try await control(["action": "state"])
+        let log = try XCTUnwrap(state["log"] as? [[String: Any]])
+        XCTAssertTrue(log.contains { ($0["path"] as? String) == "/api/v1/agent/attachments/\(ids[0])/content" })
+    }
+
+    func testAttachmentCapabilityAndPickerCancellation() async throws {
+        XCTAssertTrue(app.buttons["agent-attach"].waitForExistence(timeout: 8))
+        composer.tap(); composer.typeText("Preserved attachment draft caption")
+        app.buttons["agent-attach"].tap()
+        app.buttons["Files"].tap()
+        XCTAssertTrue(app.buttons["Cancel"].firstMatch.waitForExistence(timeout: 5))
+        app.buttons["Cancel"].firstMatch.tap()
+        XCTAssertEqual(composer.value as? String, "Preserved attachment draft caption")
+        app.buttons["agent-attach"].tap(); app.buttons["Photo Library"].tap()
+        XCTAssertTrue(app.buttons["Cancel"].firstMatch.waitForExistence(timeout: 5))
+        app.buttons["Cancel"].firstMatch.tap()
+        XCTAssertEqual(composer.value as? String, "Preserved attachment draft caption")
+        capture("agent-attachment-pickers-cancelled")
+        try await control(["action": "capability", "enabled": false])
+        app.terminate(); app.launch(); openAgent()
+        XCTAssertFalse(app.buttons["agent-attach"].exists)
+        XCTAssertEqual(composer.value as? String, "Preserved attachment draft caption")
+        try clearComposer()
+        capture("agent-text-only-capability")
+    }
+
+    func testPhotoSelectionToAttachmentOnlySend() async throws {
+        try XCTSkipIf(true, "Manual/device pre-release check: iOS 26.5 XCTest Photos authorization, callback isolation and cleanup are unreliable in this fixture. Selection-to-send is NOT validated; keep the general suite free of photo mutations.")
+        // Only synthetic assets are touched; no unrelated photo bytes are read.
+        if PHPhotoLibrary.authorizationStatus(for: .readWrite) != .authorized {
+            // XCTest's synchronous UI waits must not block the authorization request.
+            let permission = Task.detached { await PHPhotoLibrary.requestAuthorization(for: .readWrite) }
+            try await Task.sleep(for: .milliseconds(300))
+            let allow = XCUIApplication(bundleIdentifier: "com.apple.springboard").buttons.matching(
+                NSPredicate(format: "label IN %@", ["Allow Full Access", "Allow Access to All Photos", "Allow Access"])).firstMatch
+            if allow.waitForExistence(timeout: 5) { allow.tap(); _ = await permission.value }
+            else if PHPhotoLibrary.authorizationStatus(for: .readWrite) != .notDetermined { _ = await permission.value }
+        }
+        try XCTSkipUnless(PHPhotoLibrary.authorizationStatus(for: .readWrite) == .authorized,
+                          "Simulator Photos authorization \(PHPhotoLibrary.authorizationStatus(for: .readWrite).rawValue) is unavailable to \(Bundle.main.bundleIdentifier ?? "test runner")")
+        // Recover only fixtures from an interrupted test, identified by BOTH our unique
+        // date and original-filename prefix, before creating this run's asset.
+        let options = PHFetchOptions()
+        options.predicate = NSPredicate(format: "creationDate == %@", ISO8601DateFormatter().date(from: "2099-12-31T20:00:00Z")! as NSDate)
+        let previous = PHAsset.fetchAssets(with: .image, options: options)
+        let owned = previous.objects(at: IndexSet(integersIn: 0..<previous.count)).filter {
+            PHAssetResource.assetResources(for: $0).contains { $0.originalFilename.hasPrefix("sybil-attachment-ui-") }
+        }.map(\.localIdentifier)
+        if !owned.isEmpty { try await removeSyntheticPhotos(owned) }
+        let name = "sybil-attachment-ui-" + UUID().uuidString + ".png"
+        let url = FileManager.default.temporaryDirectory.appendingPathComponent(name)
+        let photo = UIGraphicsImageRenderer(size: CGSize(width: 96, height: 64)).image { context in
+            UIColor.systemPurple.setFill(); context.fill(CGRect(x: 0, y: 0, width: 96, height: 64))
+        }
+        try XCTUnwrap(photo.pngData()).write(to: url)
+        defer { try? FileManager.default.removeItem(at: url) }
+        nonisolated(unsafe) var assetID: String?
+        try await PHPhotoLibrary.shared().performChanges { @Sendable in
+            let creation = PHAssetCreationRequest.forAsset()
+            // A unique synthetic date lets us find this asset without enumerating other photos.
+            creation.creationDate = ISO8601DateFormatter().date(from: "2099-12-31T20:00:00Z")
+            let options = PHAssetResourceCreationOptions(); options.originalFilename = name
+            creation.addResource(with: .photo, fileURL: url, options: options)
+            assetID = creation.placeholderForCreatedAsset?.localIdentifier
+        }
+        let ownedID = try XCTUnwrap(assetID)
+        let identity = XCTAttachment(string: ownedID); identity.name = "synthetic-photo-owned-identifier"; identity.lifetime = .keepAlways; add(identity)
+        addTeardownBlock { try await Self.eraseSyntheticPhotos([ownedID]) }
+        do { try await exercisePhotoSelection() }
+        catch {
+            try await removeSyntheticPhotos([ownedID])
+            throw error
+        }
+        try await removeSyntheticPhotos([ownedID])
+    }
+
+    private func removeSyntheticPhotos(_ identifiers: [String]) async throws {
+        try await Self.eraseSyntheticPhotos(identifiers)
+        let evidence = XCTAttachment(string: "Removed \(identifiers.count) synthetic asset(s) by owned identifier; remaining count 0.")
+        evidence.name = "synthetic-photo-cleanup"; evidence.lifetime = .keepAlways; add(evidence)
+    }
+
+    nonisolated private static func eraseSyntheticPhotos(_ identifiers: [String]) async throws {
+        try await Task.detached {
+            let owned = PHAsset.fetchAssets(withLocalIdentifiers: identifiers, options: nil)
+            if owned.count > 0 { try await PHPhotoLibrary.shared().performChanges { PHAssetChangeRequest.deleteAssets(owned) } }
+            let remaining = PHAsset.fetchAssets(withLocalIdentifiers: identifiers, options: nil).count
+            XCTAssertEqual(remaining, 0)
+            print("Synthetic photo cleanup: \(identifiers.count) owned identifier(s), \(remaining) remaining.")
+        }.value
+    }
+
+    private func exercisePhotoSelection() async throws {
+        app.activate()
+        XCTAssertFalse(app.buttons["agent-send"].isEnabled)
+        app.buttons["agent-attach"].tap(); app.buttons["Photo Library"].tap()
+        let cell = app.descendants(matching: .any).matching(NSPredicate(format:
+            "label BEGINSWITH %@ AND NOT label CONTAINS %@", "Photo, December 31, 2099", ", Photo,")).firstMatch
+        XCTAssertTrue(cell.waitForExistence(timeout: 8))
+        cell.tap()
+        app.buttons.matching(NSPredicate(format: "label BEGINSWITH %@", "Add")).firstMatch.tap()
+        let ready = XCTNSPredicateExpectation(predicate: NSPredicate(format: "enabled == true"), object: app.buttons["agent-send"])
+        await fulfillment(of: [ready], timeout: 15)
+        XCTAssertFalse(app.buttons["agent-upload-retry"].exists)
+        capture("agent-photo-upload-ready")
+        app.buttons["agent-send"].tap()
+        let fallback = app.staticTexts.containing(NSPredicate(format: "label BEGINSWITH %@", "Attached: ")).firstMatch
+        XCTAssertTrue(fallback.waitForExistence(timeout: 12))
+        XCTAssertFalse(app.buttons["agent-retry"].exists)
+        let state = try await control(["action": "state"])
+        let requests = try XCTUnwrap(state["requests"] as? [String: [String: Any]])
+        XCTAssertEqual(requests.count, 1)
+        let submission = try XCTUnwrap(requests.values.first)
+        XCTAssertEqual((submission["_payload"] as? [Any])?.first as? String, "")
+        XCTAssertEqual((submission["attachmentIds"] as? [String])?.count, 1)
+        capture("agent-photo-attachment-only-canonical")
+        app.terminate(); app.launch(); openAgent()
+        XCTAssertTrue(app.staticTexts.containing(NSPredicate(format: "label BEGINSWITH %@", "Attached: ")).firstMatch.waitForExistence(timeout: 8))
+        XCTAssertFalse(app.buttons["agent-retry"].exists)
+        capture("agent-photo-attachment-only-reloaded")
+    }
+
     func testSendQueueToolsAndRetry() async throws {
         capture("agent-history")
         send("first fixture")

ios/Tests/SybilUITests/TranscriptFadeUITests.swift

@@ -0,0 +1,138 @@
+import XCTest
+import UIKit
+
+/// Loopback-only regressions. No picker selection or external backend writes.
+@MainActor
+final class TranscriptFadeUITests: XCTestCase {
+    private let app = XCUIApplication()
+
+    override func setUp() async throws {
+        continueAfterFailure = false
+        XCUIDevice.shared.orientation = .portrait
+        try await control(["action": "reset", "count": 160])
+        try await control(["action": "transcript-comparison"])
+        app.launchArguments = ["-sybil.ios.apiBaseURL", "http://127.0.0.1:8799/api", "-sybil.ios.adminToken", "fixture-token"]
+        app.launch()
+    }
+
+    override func tearDown() async throws { app.terminate() }
+
+    private func showSidebar() {
+        if !app.buttons["agent-sidebar"].isHittable {
+            XCTAssertTrue(app.buttons["Show sidebar"].waitForExistence(timeout: 15))
+            app.buttons["Show sidebar"].tap()
+        }
+        XCTAssertTrue(app.buttons["agent-sidebar"].waitForExistence(timeout: 5))
+    }
+
+    private func openAgent() {
+        showSidebar()
+        app.buttons["agent-sidebar"].tap()
+        XCTAssertTrue(app.textFields["agent-composer"].waitForExistence(timeout: 8) || app.textViews["agent-composer"].exists)
+        XCTAssertTrue(app.staticTexts["History message 160: local simulator fixture."].waitForExistence(timeout: 8))
+    }
+
+    private var composer: XCUIElement {
+        app.textFields["agent-composer"].exists ? app.textFields["agent-composer"] : app.textViews["agent-composer"]
+    }
+
+    private var transcript: XCUIElement {
+        // The tablet sidebar is also a scroll view; select the detail by its content.
+        app.scrollViews.containing(.staticText, identifier: "History message 160: local simulator fixture.").firstMatch
+    }
+
+    private func capture(_ name: String) {
+        let attachment = XCTAttachment(screenshot: XCUIScreen.main.screenshot())
+        attachment.name = name; attachment.lifetime = .keepAlways; add(attachment)
+    }
+
+    @discardableResult private func control(_ value: [String: Any]) async throws -> [String: Any] {
+        var request = URLRequest(url: URL(string: "http://127.0.0.1:8799/control")!)
+        request.httpMethod = "POST"; request.httpBody = try JSONSerialization.data(withJSONObject: value)
+        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        let (data, response) = try await URLSession.shared.data(for: request)
+        XCTAssertEqual((response as? HTTPURLResponse)?.statusCode, 200)
+        return try XCTUnwrap(JSONSerialization.jsonObject(with: data) as? [String: Any])
+    }
+
+    func testSharedHeaderFadeGeometry() async throws {
+        showSidebar()
+        let chat = app.buttons.containing(NSPredicate(format: "label CONTAINS %@", "Transcript fade comparison")).firstMatch
+        XCTAssertTrue(chat.waitForExistence(timeout: 8)); chat.tap()
+        // Normal chat is lazy and can open at either end on phone/tablet.
+        let normal = app.scrollViews.containing(NSPredicate(format: "label BEGINSWITH %@", "History message ")).firstMatch
+        XCTAssertTrue(normal.waitForExistence(timeout: 8))
+        let normalTop = normal.frame.minY
+        let first = app.staticTexts["History message 1: local simulator fixture."]
+        if first.exists && first.isHittable { normal.swipeUp(velocity: .slow) }
+        else { normal.swipeDown(velocity: .slow) }
+        capture("normal-chat-content-crossing-shared-fade")
+        XCTAssertTrue(app.buttons["Attach file"].isHittable)
+
+        openAgent()
+        let scroll = transcript
+        XCTAssertTrue(scroll.exists)
+        scroll.swipeDown(velocity: .slow)
+        XCTAssertTrue(app.buttons["agent-jump-latest"].waitForExistence(timeout: 5))
+        capture("agent-content-crossing-shared-fade")
+        XCTAssertTrue(composer.isHittable)
+        XCTAssertTrue(app.buttons["agent-attach"].isHittable)
+        XCTAssertTrue(app.buttons["agent-send"].exists)
+        // A viewport padded below the header clips bubbles before they reach its fade.
+        XCTAssertEqual(scroll.frame.minY, normalTop, accuracy: 1,
+                       "Agent must scroll beneath the same workspace header as normal chat")
+    }
+
+    func testReadingPositionUnreadAndKeyboardUnderSharedFade() async throws {
+        openAgent()
+        let scroll = transcript
+        XCTAssertTrue(app.staticTexts["History message 160: local simulator fixture."].isHittable)
+        scroll.swipeDown(velocity: .slow)
+        scroll.swipeDown(velocity: .slow)
+        XCTAssertTrue(app.buttons["agent-jump-latest"].waitForExistence(timeout: 5))
+        // Stay below the header's content clearance, where text is readable.
+        let visibleTop = scroll.frame.minY + 100
+        let anchor = try XCTUnwrap(app.staticTexts.matching(NSPredicate(format: "label BEGINSWITH %@", "History message")).allElementsBoundByIndex.first {
+            $0.isHittable && $0.frame.minY > visibleTop && $0.frame.maxY < composer.frame.minY
+        })
+        let before = anchor.frame.minY
+        let stateBefore = try await control(["action": "state"])
+        try await control(["action": "reply", "content": "Fade regression reply while reading"])
+        let unread = XCTNSPredicateExpectation(predicate: NSPredicate(format: "label CONTAINS %@", "unread"), object: app.buttons["agent-jump-latest"])
+        await fulfillment(of: [unread], timeout: 8)
+        XCTAssertEqual(anchor.frame.minY, before, accuracy: 2)
+        let stateAfter = try await control(["action": "state"])
+        XCTAssertEqual(stateAfter["readCursor"] as? Int, stateBefore["readCursor"] as? Int)
+        XCTAssertLessThan(try XCTUnwrap(stateAfter["readCursor"] as? Int), try XCTUnwrap(stateAfter["cursor"] as? Int))
+        capture("agent-fade-reading-position-and-unread")
+
+        for _ in 0..<30 {
+            if app.buttons["Load earlier messages"].isHittable { break }
+            scroll.swipeDown(velocity: .fast)
+        }
+        let load = app.buttons["Load earlier messages"]
+        XCTAssertTrue(load.isHittable)
+        let first = app.staticTexts["History message 61: local simulator fixture."]
+        let beforeLoad = first.frame.minY
+        load.tap()
+        capture("agent-fade-prepend-reading-position")
+        XCTAssertEqual(first.frame.minY, beforeLoad, accuracy: 3,
+                       "Prepending must preserve the readable row's position beneath the header")
+
+        app.buttons["agent-jump-latest"].tap()
+        let latest = app.staticTexts["Fade regression reply while reading"]
+        let followed = XCTNSPredicateExpectation(predicate: NSPredicate(format: "hittable == true"), object: latest)
+        await fulfillment(of: [followed], timeout: 5)
+        composer.tap()
+        XCTAssertTrue(latest.isHittable)
+        XCTAssertTrue(app.buttons["agent-attach"].isHittable)
+        capture("agent-fade-latest-with-keyboard")
+        // No send: this only changes a local draft, then clears it.
+        composer.typeText("Fade draft\nsecond line\nthird line")
+        XCTAssertTrue(latest.isHittable)
+        composer.typeText(String(repeating: XCUIKeyboardKey.delete.rawValue, count: "Fade draft\nsecond line\nthird line".count))
+        try await Task.sleep(for: .milliseconds(500))
+        let read = try await control(["action": "state"])
+        XCTAssertEqual(read["readCursor"] as? Int, read["cursor"] as? Int)
+    }
+}