Three I/O Modes

Fresh

Source: BIBLE.md (Three I/O backends), bible/understand-everything.md (The three modes)

Every browser session runs in one of three modes, dispatched by hybrid-router.mjs.

Mode comparison

Mode	Input source	CDP traces	Use case	Latency
Ghost	OS-level (desktop) or ADB (mobile) plus vision	Zero	Reddit, LinkedIn, Facebook, Instagram, Nextdoor	~50 ms (desktop), ~20 ms (mobile)
Hybrid	OS-level for clicks/typing, CDP for reading	Minimal (reads only)	Yelp, Substack, Gmail	~50 ms input, ~5 ms reads
Speed	Pure CDP (same as V1)	Full	YouTube, Google Search	~5 ms

Per-platform defaults

ghost:  reddit, linkedin, facebook, instagram, twitter, nextdoor
hybrid: yelp, substack, gmail
speed:  youtube, google

Backends

Three I/O backends decide where the events actually go:

Backend	Use	isTrusted
cdp	Puppeteer, desktop, speed mode default	false
os	Windows SendInput, desktop, ghost and hybrid mode default	true
adb	Android Debug Bridge, mobile, always forces ghost mode	true

Mode plus backend selection

flowchart TD
  L[POST /browser/launch] --> P{platform default}
  P -- reddit --> G[mode=ghost, backend=os]
  P -- yelp --> H[mode=hybrid, backend=os]
  P -- google --> S[mode=speed, backend=cdp]
  L -. override .-> O[Explicit mode in body]
  M[POST /mobile/connect] --> A[mode=ghost, backend=adb]

Why three modes exist

V1's CDP-only architecture has a ceiling. Platforms like Reddit, LinkedIn, and Facebook check whether input events came from real hardware. CDP produces isTrusted: false on every event. That is a dead giveaway.

Ghost Engine fixes this with three new capabilities. The router picks which mode is needed per platform.

Ghost mode

Everything OS-level or ADB plus vision. Zero CDP interaction traces.

• Mouse clicks go through Windows SendInput. isTrusted: true
• Keyboard goes through Windows SendInput. isTrusted: true
• Navigation uses vision: screenshot to VLM to coordinates
• Zero CDP interaction traces

Hybrid mode

Best of both worlds. OS-level for the things that matter for detection (clicks and typing). CDP for reads (which do not leave detectable traces).

• Clicks and typing OS-level (isTrusted: true)
• Reads, navigation, evaluation, cookies via CDP

Speed mode

Identical to V1. Maximum throughput, full CDP traces.

• All input via CDP Input.dispatchMouseEvent/KeyEvent
• All reads via CDP
• isTrusted is false
• Multiple parallel sessions allowed

How to use each mode

Launch with a specific mode

# Ghost mode (default for Reddit)
curl -s -X POST http://localhost:4700/browser/launch \
  -H "Content-Type: application/json" \
  -H "x-api-key: ghost-engine-key" \
  -d '{"email":"someone@gmail.com","mode":"ghost","platform":"reddit","headless":false}'

# Hybrid mode for Yelp
curl -s -X POST http://localhost:4700/browser/launch \
  -H "Content-Type: application/json" \
  -H "x-api-key: ghost-engine-key" \
  -d '{"email":"someone@gmail.com","mode":"hybrid","platform":"yelp","headless":false}'

# Speed mode for YouTube (default)
curl -s -X POST http://localhost:4700/browser/launch \
  -H "Content-Type: application/json" \
  -H "x-api-key: ghost-engine-key" \
  -d '{"email":"someone@gmail.com","mode":"speed","platform":"youtube","headless":false}'

Switch mode mid-session

curl -s -X POST http://localhost:4700/browser/abc123/set-mode \
  -H "Content-Type: application/json" \
  -d '{"mode":"speed"}'

Mobile (always ghost)

curl -s -X POST http://localhost:4700/mobile/connect \
  -H "Content-Type: application/json" \
  -d '{"serial":"192.168.1.100:5555"}'

The router automatically sets mode=ghost, backend=adb, vision=true.

RouterSession class

Tracks per-session state:

• instanceId: session ID
• mode: ghost, hybrid, or speed
• backend: cdp, os, or adb
• serial: ADB device (mobile only)
• vision: whether vision-based navigation is enabled
• platform: platform identifier (reddit, yelp, etc.)
• windowBounds: cached for OS mode (5-second refresh)
• screenSize: cached for ADB mode

Cost control

Vision is expensive: about $0.003 per VLM call (Claude Sonnet). Use it only for navigation decisions in ghost mode. Data reads (get text, check URL, extract content) always go through CDP regardless of mode.

Constraints

• One desktop ghost session at a time. SendInput goes to the foreground window
• Mobile ghost sessions are unlimited. Each ADB session targets a unique serial
• Ghost mode requires window focus on desktop
• Vision calls have probabilistic accuracy. Use a 0.5 confidence threshold with 2 retries