Your self-hosted AI agent, now in your pocket.

You self-hosted your AI agent for privacy and control. Then you open a browser on your phone, navigate to a web UI that wasn't designed for a 6-inch screen, and watch streaming responses stutter in a non-native view.

The hermes-webui browser UI technically works on mobile via Cloudflare Tunnel — but it wasn't designed for it. You lose the native iOS feel, streaming stutters in a web view, your session state vanishes if the screen turns off, and your server password sits in browser state instead of the Keychain.

You went through the trouble of self-hosting for privacy and control. You deserve an interface that takes mobile seriously.

The problem

The gapNative streaming, offline cache, Keychain auth, Live Activities, App Intents — none of these exist in a browser wrapper. They only exist in a real native app.

Hermex (Xcode target: HermesMobile) is a SwiftUI app, free on the App Store, that talks exclusively to your own hermes-webui server over HTTPS. The phone is the control plane. The server is the execution plane.

Everything your agent can do — start sessions, watch responses stream token-by-token, steer or stop a run, manage tasks and skills, browse the workspace file system — you can do from your iPhone. No relay. No telemetry. No cloud.

The architecture is deliberately minimal: the app is a control surface that never touches your models or your data. Your server handles all compute. Hermex handles all mobile interaction quality.

The big idea

Hermex does something architecturally elegant — it never tries to run AI models on the device. Instead, it uses Server-Sent Events to stream the server's output in real time, the same way browsers do, but consumed by a native URLSession-based SSE client.

This means the app is fast, battery-efficient, and completely model-agnostic. You can switch between GPT-4, Claude, Gemini, or any local model your server supports — Hermex just streams whatever the server emits.

When Cloudflare closes the SSE connection during quiet periods (a known risk for long-running quiet streams), the app detects the drop, queries GET /api/chat/stream/status, confirms the run is still active, and reattaches via a new GET /api/chat/stream?stream_id=... — using the same stream_id the server already knows about. Your message was never sent twice.

The aha

One POST sends the message. If the SSE connection drops, the app reattaches to the same stream_id — never resending your message, never losing progress.

Clean separation of concerns: a Swift actor-based API client owns all HTTP, an SSE client owns the streaming connection, feature modules own their UI and state, and SwiftData owns the offline cache.

The main target (HermesMobile) is organized into Auth, Networking, Persistence, and feature modules (Chat, Sessions, Tasks, Skills, Workspace, Memory, Insights). Two extension targets handle the Dynamic Island live activity (HermesLiveActivityWidget) and the iOS share sheet (HermesShareExtension).

The Networking layer's APIClient is a Swift actor — meaning all HTTP state is protected from data races by the Swift concurrency model. It has 13 extensions, one per domain (chat, sessions, tasks, skills, workspace, memory, TTS, transcribe, etc.). The SSEClient wraps LDSwiftEventSource and handles reconnect logic transparently.

Architecture

Data flow

Hermex is a tool for developers and power users who self-host their AI infrastructure. Here's who it's for:

In the real world

Hermex is a client only — you bring your own hermes-webui server. Prerequisites: a machine you control (Mac, Linux, or Windows/WSL2), Python 3.11+, Cloudflare Tunnel or Tailscale for HTTPS, and an iPhone on iOS 18+.

App Store (free) · or build from source with Xcode 26+

1. Run the server pip install hermes-webui && HERMES_WEBUI_PASSWORD=yourpassword hermes-webui — the server starts on port 8787. Verify: curl http://localhost:8787/health → {"status":"ok"}.
2. Expose over HTTPS cloudflared tunnel --url http://localhost:8787 — gives you a real HTTPS URL (e.g. https://random-name.trycloudflare.com). iOS App Transport Security needs real HTTPS. Tailscale (100.64.x.x range) also works for plain HTTP within the mesh.
3. Download Hermex (free) Search Hermex on the App Store, or go to apps.apple.com/app/hermex/id6767006319. No account required, no subscription.
4. Connect Open Hermex → enter your HTTPS URL and password → tap Test Connection. A green checkmark means the app hit GET /health successfully. You land on the session list.
5. Start your first session Tap + → choose workspace and model → type your prompt → send. You'll see tokens appear character-by-character in a native SwiftUI bubble, with tool-call detail and thinking blocks expandable inline.

This explainer ships a downloadable AI knowledge pack: a portable RVF knowledge base your AI assistant can query to deeply understand the Hermex codebase — the same KB that grounded every claim on this page. It includes the full primer, structured module index, and the ask-kb tool for conversational querying.