name: hydrogen-api description: > Complete reference for Hydrogen control API endpoints. The control API runs on a dynamic port (find it via port discovery). Use these endpoints to drive Hydrogen programmatically: manage the workspace runtime, control Claude Code, manipulate VS Code, manage workspace tabs, run setup steps, trigger virgin reset, and more. ~159 endpoints. Two self-documenting sources of truth list them live: GET /_manifest (curated grouped list) and GET /test/help (the /test/* diagnostics). Trigger words: Hydrogen API, control API, Hydrogen endpoint, container exec, claude api, iframe eval, workspace tabs, setup run-all, runtime status, reload vscode, browser profiles, open url, virgin reset api, diagnostics, ad health, test window-tree, ai cursor, setup panel, screenshot mode.

Hydrogen Control API Reference

The control API exposes ~159 endpoints. Don't trust a static count or list in this file to stay exhaustive — the API is self-documenting, with two live sources of truth you should hit first:

Source What it gives you Where
GET /_manifest Curated, grouped, machine-readable list of the highest-value endpoints (path, method, args, description, visibility). hd_api forwards anything not listed. lib.rs:9144
GET /test/help Lists the /test/* diagnostics (window enumeration, UIA click, dialog classification, cascade reset). Gated behind HD_TEST_API_ENABLED=1. lib.rs:9723

Base URL: http://127.0.0.1:<dynamic> — the loopback address. The port is dynamic per launch; read the live URL from ~/.adom/hydrogen-control-url — see "Finding the Control Port" below.

Finding the Control Port

The control API port is dynamic (default 47084, auto-resolves conflicts).

# From Hydrogen log
adom-bridge-cli hd_log '{"tail":100}' | grep "control="

# From inside the workspace — USE THIS. Hydrogen writes its live control URL to a discovery
# file every launch, so you never hunt for the dynamic port:
CTRL="$(cat ~/.adom/hydrogen-control-url)"; curl -sf "$CTRL/health"

From the workspace, read ~/.adom/hydrogen-control-url (e.g. http://127.0.0.1:<control>) — a file, NOT an env var (your non-interactive Bash shells don't source .bashrc/profile.d). Hydrogen rewrites it with the live dynamic port every launch. This is the channel for the UI command bus, the live ports map, Claude control, etc. — distinct from adom-cli (ADOM_HYDROGEN_URL → SSE), which is unchanged for web-hydrogen parity.

For the host-side ways to discover the port (Hydrogen log / the ports file) and the runtime-specific host endpoints, see the platform companion skills (hydrogen-api-windows / hydrogen-api-mac).

Health & Status

Method Path Description
GET /health Hydrogen alive check — returns {ok, port, service}
GET /buildinfo Running build git SHA + build metadata (the only trustworthy "did my build ship?" check)
GET /ports The 4 editable PortConfig ports (proxy, control, cdp, code_server)
GET /ports/all LIVE full port map — every port Hydrogen has bound, with status info

ab-health diagnostics (/ad/*)

These verify the adom-bridge-cli / relay / embedded-ab half of Hydrogen is alive (the bridge that connects this cloud container to Hydrogen). All GET, all return {ok, ...}.

Method Path Description
GET /ad/health Overall embedded-ab health roll-up
GET /ad/process Is the adom-bridge-cli process running
GET /ad/embedded Embedded-ab module status
GET /ad/workspace-direct ⭐ The converged check — direct path to the workspace relay (use this one)
GET /ad/relay Relay (WS/HTTP) reachability
GET /ad/liveness-beacon Liveness beacon freshness
GET /ad/direct-api Direct-API reachability
GET /ad/discovery-file Discovery file present + parseable

Driving Hydrogen's UI (command bus)

Open/close/toggle any Hydrogen menu, dialog, or panel — the first-class alternative to CDP clicking. See the hydrogen-ui skill.

Method Path Body Description
GET /ui/actions List every drivable UI action {id,label,description,group} (+ _hints)
POST /ui/invoke {"id":"ports.open"} Run a UI action; returns {ok,value} only after the frontend ran it
GET /auth-token Hydrogen session token
GET /setup-status Overall setup completion state
GET /diagnostics/all Run all diagnostic checks
GET /diagnostics/{name} Run a single diagnostic check

Workspace / Container Management

These endpoints manage the active workspace runtime.

Method Path Body Description
GET /container-status Workspace runtime available, image/distro present, workspace exists/running
GET /container-stats CPU, memory, disk usage
POST /container-restart Restart the active workspace runtime (5s timeout)
POST /container-stop Stop the active workspace runtime
POST /container-exec {"command":"..."} Run command in the workspace as user adom
POST /container-delete Remove the workspace
POST /image-delete Remove workspace image
GET /container-images List available workspace images
POST /container-switch-image {"image":"..."} Switch to different image
POST /container-pull-image {"image":"..."} Pull an image
GET /container/logs Workspace stdout/stderr
GET /container/env Workspace environment variables
GET /container/ports Published port mappings
GET /container/disk Disk usage inside the workspace
POST /container/restart Alias for /container-restart

Runtime-specific endpoint tables (including the legacy Docker-only endpoints) live in the platform companion skills (hydrogen-api-windows / hydrogen-api-mac).

WebView & VS Code

Method Path Body Description
POST /eval {"js":"..."} JS eval in main Hydrogen webview
POST /iframe-eval {"js":"...","contextIndex":N} JS eval in a specific iframe context (0-14)
POST /cdp-eval {"expression":"..."} Direct Chrome DevTools Protocol eval
POST /click {"x":N,"y":N} Click at coordinates in webview
POST /mouse-click {"x":N,"y":N,"button":"left"} Mouse click with options
POST /query {"selector":"..."} Query DOM elements
POST /reload-vscode Reload the VS Code iframe
POST /vscode/hide-activity-items Hide activity-bar items (persisted, overflow-proof)
GET /targets List CDP targets (all webview contexts)
GET /cdp-info CDP connection info (port, URL)
GET /devtools DevTools status

AI cursor (visible cursor for demos / clicking)

Distinct from /click and /mouse-click — this renders a visible AI cursor, glides it, and can click. Use for demos or when the user should see where the AI clicks.

Method Path Body Description
POST /ai-cursor/move {"x":N,"y":N} Move (glide) the visible AI cursor to coordinates
POST /ai-cursor/click {"x":N,"y":N} Move the visible AI cursor there + click
POST /ai-cursor/hide Hide the visible AI cursor

Screenshot primitives

Method Path Body Description
GET /capture/viewport Capture the Hydrogen webview viewport (PNG)
POST /shot {...} Screenshot primitive (see hydrogen-self-screenshot for the full workflow)

Port hints

Method Path Body Description
GET /adom-port-hints Read the workspace port-hints map
POST /adom-port-hints {...} Write/merge the workspace port-hints map

Claude Code

Status / auth state (GET)

Method Path Description
GET /claude/status Install state, auth, active session, version
GET /claude/auth-check Deep auth check — file exists, token, expiry
GET /claude/auth-status Auth-status detail
GET /claude/auth-page-state Which auth screen the panel shows: continue-in-browser | subscription-button | chat; returns oauth_url + at_browser_auth_gate
GET /claude/detect-auth-failure Scan webview contexts for auth button/errors
GET /claude/sessions List active Claude sessions

Auth actions (POST)

Method Path Body Description
POST /claude/find-auth-button Find + highlight the sign-in button WITHOUT clicking (validation)
POST /claude/start-auth Find + highlight + CLICK the "Claude.ai Subscription" button to begin OAuth
POST /claude/trigger-auth Alias for start-auth
POST /claude/detect-state Detect current auth/panel state
POST /claude/authorize-in-browser {"timeout_ms":N,"dry_run":B,"fresh":B,"oauth_url":"..."} Auto-click the "Authorize" button on the claude.ai OAuth page (unattended sign-in)
POST /claude/authorize-tab-enter Approve the Adom OAuth tab via Enter (branded picker flow)
POST /claude/inject-creds Push host backup credentials into the workspace
POST /claude/wipe-creds {"backup":B} Wipe Claude credentials (destructive); backup:false keeps the host backup so reinject can restore

Panel / conversation control (POST unless noted)

Method Path Body Description
POST /claude/open Open Claude Code panel (claude-vscode.editor.open)
POST /claude/ensure-open Ensure the panel is open (strict readiness; recovery if not rendered)
POST /claude/open-with-message {"message":"..."} Open + pre-fill message
POST /claude/focus Focus Claude panel
POST /claude/new-conversation Start a fresh conversation (shows sign-in panel when unauthenticated)
POST /claude/new-chat-and-send {"text":"...","typed":B,"submit":B,"delay_ms":N} Open fresh conversation, wait for compose box, type + (default) submit
POST /claude/submit Find + click send button
POST /claude/send {"message":"..."} Send message to Claude
POST /claude/inject {"message":"..."} Inject text into the compose box
POST /claude/inject-message {"message":"..."} Inject into conversation
POST /claude/type-and-submit {"message":"...","delay_ms":N} Type char-by-char (human-paced) + submit
POST /claude/remote-control {"name":"..."} Turn on Claude Code Remote Control (submits /remote-control slash command)
POST /claude/highlight-open-button {"duration":N} Glow animation on Claude button
POST /claude/clear-open-highlight Clear the open-button highlight

OAuth & Auth

Method Path Body Description
POST /claude-auth Full PKCE OAuth flow — opens browser, sets up callback
GET /oauth/callback OAuth callback handler (receives auth code)
POST /auth/proxy varies Proxy auth requests to carbon.adom.inc
POST /open-url {"url":"..."} Open URL (triggers browser picker)
POST /start-oauth-proxy {"port":N} Start OAuth callback proxy on a port
GET /browser-profiles List browsers + profiles with avatars
POST /open-in-profile {"url":"...","browser":"...","profileDir":"..."} Open URL in specific browser profile
POST /browser-picker/opened {...} Frontend reports the browser picker was opened
GET /browser-picker/last-open Last browser-picker open event

Setup Steps & Setup Panel

State / trigger / step control

Method Path Body Description
GET /setup/state Get current setup state (never-run | in-progress | complete)
POST /setup/state {"state":"..."} Set setup state
POST /setup/step/<id> {"continue_after":B} ⭐ Run one step by id (forces panel visible first); continue_after:true runs this step + every step after it
POST /setup/force-close Force-close setup panel
POST /setup/countdown {"seconds":N,"message":"..."} Show countdown overlay
GET /setup/trigger Read trigger file
DELETE /setup/trigger Delete trigger file
POST /config-reset Reset Hydrogen config

REFUSED as deprecated (headless runs with no visible UI): POST /setup/run-all, POST /setup/run-step, POST /setup/virgin-reset. They return a refusal pointing at the UI-visible path. To run steps: use POST /setup/step/<id> or relaunch Hydrogen to auto-run the cascade.

Setup panel control

Method Path Body Description
POST /setup/panel/show Force the setup panel visible
POST /setup/panel/hide Hide the setup panel
POST /setup/panel/show-virgin-reset Show panel + expand the Virgin Reset section
POST /setup/panel/virgin/show Show the Virgin Reset section only
POST /setup/panel/virgin/hide Hide the Virgin Reset section
POST /setup/panel/set-virgin-options {"options":{...}} Set the virgin-reset checkboxes
POST /setup/panel/run-virgin-reset ⭐ The ONLY allowed virgin-reset trigger — UI-visible by construction (shows panel + checkboxes + progress before deleting anything)
POST /setup/panel/wipe-keep-auth Synchronous wipe that KEEPS Adom + Claude tokens
POST /setup/screenshot-mode {"enabled":B} Toggle per-step screenshot capture (default OFF)
GET /setup/screenshot-mode Whether per-step screenshot mode is on

Workspace Tabs

Method Path Body Description
GET /workspace/tabs List all workspace tabs
GET /workspace/tabs/find?name=X Find tab by name (404 if not found)
POST /workspace/tabs {tab spec} Add a new tab

App lifecycle & window

Method Path Body Description
POST /app/restart Restart the Hydrogen app (kills + respawns the binary)
POST /app/relaunch-frontend Relaunch the Hydrogen GUI (kill+respawn) while it is responsive
POST /window/foreground Bring the Hydrogen window to the foreground (unminimize + focus)

Host OS reboot (/system/*) is platform-specific — see the platform companion skills (hydrogen-api-windows / hydrogen-api-mac).

Diagnostics (/test/*)

Window enumeration, UIA clicking, native-dialog classification, and cascade diagnostics. Gated behind HD_TEST_API_ENABLED=1 (return 404 / "test API disabled" otherwise). GET /test/help self-lists the whole cluster.

Method Path Body Description
GET /test/help Self-lists every /test/* endpoint
GET /test/window-tree Enumerate all visible top-level windows
POST /test/focus {"window":"..."} Focus Hydrogen (self) or a window by title substring
POST /test/click-uia {...} Poll UIAutomation for a Button by Name; Invoke when found
GET /test/setup-steps Raw setup-steps.json + derived summary (alias: /test/install-steps)
POST /test/dump-state {...} Write a diagnostic bundle (logs, install-steps, runtime state, tasklist, window-tree)
POST /test/reset-cascade Delete install-steps.json + emit setup-reset event
POST /test/screenshot-hydrogen-window {...} Capture Hydrogen's own window to a PNG file

The /test/probe-dialogs endpoint (classifies Windows-only blocker dialogs) is Windows-specific — see the hydrogen-api-windows companion.

Key Patterns

iframe-eval context discovery

Contexts 0-14 cover all webview frames. Context numbers shift when panels open/close. Always scan, never hardcode. The Claude Code extension webview IS reachable through these contexts.

POST /iframe-eval {"js":"document.body.innerText.substring(0,100)","contextIndex":3}

container-exec

Runs as user adom inside the workspace. Use full paths (/home/adom/ not ~/). Tilde doesn't expand through the exec chain.

POST /container-exec {"command":"ls /home/adom/project"}

Trigger setup re-run after completion

The trigger file poller STOPS when all steps are done. Use the step API instead:

POST /setup/step/<id> {"continue_after": true}