feat(mobile): preview agent devices with scoped stream access

[rynfar]

What changed

Mobile now shows device sessions for the current thread and opens a full-screen viewer with live video and controls. The viewer shares Pylon's device stream transport with web, keeps host identity when switching devices, and stops decoding when the viewer loses focus, the app backgrounds, or the route closes.

Simulator testing exposed two release-blocking bugs in the first draft: the live subscription's waiting flag kept the preview button hidden even after a valid session arrived, and the iOS full-screen modal hid its Close, Home, and device menu controls. Device inventory is now tied to the exact RPC session and supervisor generation; the iOS header is visible from the modal's initial render. Stream tickets remain fenced to the prepared connection and generation, and neither React keys nor errors contain ticket material.

Adapted from upstream sources 823119350ee29cca434b1295aa5c560f4c9ef98a and the shared/mobile recovery portions of 9f73ca3677; Pylon's existing web recovery remains in place.

iOS evidence

Before the final fix, the viewer streamed the device but had no native controls:

After the fix, an iPhone 17 showed a live iPhone 16e Settings screen with Close, device options, and Home controls:

Validation

• 90 focused mobile, shared-runtime, and web device tests passed; mobile, web, and client-runtime typechecks passed.
• Scoped lint, format, and diff checks passed. The generated mobile WebView stream bundle built successfully.
• Isolated iOS Simulator verification used a synthetic thread and separate viewer/target simulators. The viewer updated when the target opened Settings; Home moved the target to the iOS home screen. The device menu opened, and Close returned to the thread.
• Independent adversarial review of the reconciled feature and the simulator-driven fix found no concrete issue.

Limits

Android native rendering was not tested because this host has no Android SDK or emulator. Android has an explicit decoder error when WebCodecs is unavailable; remote Android streaming needs a secure context such as HTTPS or loopback. Older servers without device-state and hub endpoints cannot provide this viewer; the existing mobile thread UI remains usable.

Model/harness: GPT-6 Codex implementation; GPT-6 Sol (low) independent review.

[vercel]

Deployment failed for project pylon-marketing with the following error:

Resource is limited - try again in 24 hours (more than 100, code: "api-deployments-free-per-day").

Learn More: https://vercel.com/pylon-code?upgradeToPro=build-rate-limit

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	14.0 KiB	14.0 KiB	+12 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.3 KiB	7.3 KiB	−3 B (−0.0%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.7 KiB	6.7 KiB	+15 B (+0.2%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.0 KiB	58.0 KiB	+44 B (+0.1%)	66.4 KiB	✅
Codex	Live turn messages	9	10	+1 (+11.1%)	21	✅
Claude	Total thread wire	14.0 KiB	14.0 KiB	+7 B (+0.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.3 KiB	7.2 KiB	−9 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.7 KiB	6.8 KiB	+16 B (+0.2%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	58.9 KiB	58.9 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	9	9	0 (0.0%)	21	✅

Baseline: c05418c · PR result: 7ebae69 · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 115.7 KiB
• Claude decoded thread snapshot: 116.4 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

1 Skipped Deployment

Project	Deployment	Actions	Updated
pylon-marketing	Ignored	Preview	Sep 27, 2026 12:05am UTC