CONTEXT.md

Agent Device Domain Context

Terms

• Provider-backed integration scenario: device-free integration test that runs the real daemon request path and replaces only external device or host tool execution.
• Provider: request-scoped adapter interface for external device, runner, or host tool execution.
• Cloud WebDriver runtime: package-shaped ProviderDeviceRuntime implementation that maps a cloud-owned Appium/WebDriver session into agent-device lease, inventory, install, interactor, and release hooks without adding provider-specific branches to daemon routing. Cloud WebDriver adapters must expose explicit command capabilities because snapshots come from Appium page source rather than agent-device native iOS runner or Android helper backends.
• CloudArtifact: provider-hosted session output such as video, Appium logs, device logs, automation logs, or provider dashboard links. Cloud artifacts stay under the cloudArtifacts response field so they do not collide with daemon-managed local/downloadable artifacts.
• DaemonArtifactType: optional semantic category supplied by the command or adapter that owns a daemon-managed downloadable artifact, such as screenshot, screen-recording, or trace-log. Finalization and inventory code must preserve this value when present, not infer it from filenames, fields, or MIME types. Missing artifact types must not prevent artifact registration. The type documents known values while allowing provider or command owners to introduce more specific strings.
• Provider transcript: exact record of provider calls used when a test must verify platform command translation.
• Scenario transcript: command-level integration flow that describes user-visible behavior through daemon commands.
• In-process provider scenario harness: integration runner that invokes the daemon request handler directly without opening an HTTP listener.
• HTTP contract test: narrow test that verifies JSON-RPC transport, auth, and response finalization over the daemon HTTP boundary.
• Daemon RPC protocol version: integer advertised by daemon/proxy /health and checked by remote clients before HTTP JSON-RPC; bump only for breaking transport/request/response compatibility across the remote daemon boundary.
• Interactor: semantic interface between command dispatch and platform behavior.
• Platform module: platform-specific implementation behind the Interactor.
• Target: selected automation destination, such as mobile, tv, or desktop.
• Modality: broad supported device family, such as mobile, tv, or desktop.
• Session: daemon-owned state for a selected target and opened app or surface.
• Recording backend: daemon-internal module interface selected per recording target that owns platform recording validation, output path policy, start/stop execution, and record-only cleanup below the daemon recording lifecycle.
• Device lease: logical remote ownership of one selected device for a tenant/run/client and lease provider, separate from platform helper process locking.
• Device key: stable provider-scoped device identity used for lease contention, such as a simulator UDID, physical device id, or provider inventory id.
• Lease provider: remote connection source that routes and owns a device lease, such as proxy, cloud bridge, or limrun.
• Runner/process lease: backend helper mutual-exclusion guard for platform runners or tools; it is not the remote client ownership boundary.
• Host process primitive: low-level host PID helpers in src/utils/host-process.ts for liveness, start-time/command reads, process listing, process-tree expansion, PID de-duplication, and best-effort signaling. It must not own domain cleanup policy such as browser ownership markers, runner lease reclamation, daemon takeover checks, or app-log PID metadata verification.
• Command surface: catalog of public command identity, interface exposure, adapter policy, and shared command metadata across CLI, Node.js, MCP, and batch entrypoints.
• Daemon command registry: daemon-side source of truth for command route ownership and request-policy traits, including admission exemptions, session locking, selector validation, replay-scoped actions, recording invalidation, Android dialog guards, and request provider device resolution.
• Runner command traits: per-command-type classification for iOS/macOS runner lifecycle behavior, distinct from the public command surface and daemon command registry. The Swift runner traits classify interaction, read-only, and runner-lifecycle axes for XCTest execution; Swift resolves the alert command as read-only only for its get action. The TypeScript runner command traits classify daemon-side runner send/recovery policy such as read-only retry routing, readiness probes, and recent-healthy-mutation preflight skips; the TypeScript table is command-type keyed and currently classifies alert as read-only for daemon retry policy. Each side keeps one source of truth keyed by runner command type.
• Coordinate-first resolved element activation: iOS/macOS runner interaction pattern where a selector or text query resolves the semantic XCUIElement, then activation uses the element's resolved center coordinate when a frame is available. This keeps target selection semantic while avoiding XCUIElement.tap() post-action element re-resolution after normal navigation. tvOS remains focus/remote-driven.
• Interaction dispatch path: one concrete route an interaction command takes to the device (runtime selector/ref resolution, direct iOS selector, native ref via web clickRef, coordinate, maestro non-hittable fallback). Every path classifies every guarantee in the ADR 0011 registry.
• Gesture plan: typed, platform-neutral normalization of one- or two-contact gesture intent into bounded pointer trajectories. Contact topology is separate from motion; two-contact intent remains pan/pinch/rotate/transform even when native injection shares one executor. See ADR 0013.
• Android planned-touch executor: Android-local adapter seam that accepts AndroidTouchPlan—the platform-neutral GesturePlan plus Android's stationary long-press plan—and selects the paired provider-native touch/viewport adapter or bundled instrumentation-helper adapter. Scroll and long-press retain their command semantics and only share physical touch execution through this seam. Helper long-press executes its absolute stationary path without a viewport probe; provider long-press receives its paired provider-owned viewport. See ADR 0013.
• Multi-touch geometry: the internal initial span and angle plus centroid translation, scale, and rotation used to build both contact trajectories. Geometry is viewport-aware and fails early when the requested motion cannot fit; it is not a public tuning surface.
• Guarantee cell: one (dispatch path, guarantee) entry in src/contracts/interaction-guarantees.ts, classified as runtime/runner/delegated/inapplicable/waived. Completeness is a compile error; honesty is gate-tested.
• Owned waiver: a gap:-prefixed waived cell carrying a trackingIssue URL. Waivers are diffable debt with an owner, never folklore.
• Parity table: golden JSON fixture under contracts/fixtures/ consumed by both vitest and the runner's gated Swift tests, so a cross-language rule (e.g. tap-point policy) cannot drift silently. Change the rule only via the table.
• Coverage manifest: CONTRACT_COVERAGE export beside each interaction contract test file claiming which matrix cells it proves; the coverage gate requires every enforced/delegated cell to be claimed and rejects overclaims of waived cells.
• Delegation-on-error: a fast path falling back to the runtime path on semantic failure shapes. It closes failure-side guarantee cells only — never success-path parity.
• Ref generation pin: optional ~s<n> suffix on an @ref carrying the snapshot generation it was minted from. Accepted as input everywhere, emitted by no tree output (snapshot token budget), auto-appended by the MCP layer, stripped and ignored by replay.
• Settled observation: opt-in (--settle) post-action payload on press/click/fill/longpress — the quiet-window stable loop re-captures until the UI settles, and the response carries the diff vs the pre-action tree (changed lines only, added lines with fresh refs, refsGeneration when the settled tree was stored). Best-effort: never fails the action; settled: false plus a hint on never-quiet content.
• Snapshot capture plan: per-strategy ordered chain of iOS snapshot capture backends (recursive tree, query sweep, private AX) run by one plan runner under a shared wall-clock budget; recovery ordering is declared data, never a per-call-site branch.
• Snapshot quality verdict: structured outcome (state, backend, reason code, effective depth, collapsed leaves) computed once by the plan runner and shipped with every planned snapshot payload; the daemon and CLI render it instead of re-deriving degradation from node shapes.
• AX-unavailable target invalidation: iOS/macOS runner behavior where a root accessibility snapshot failure such as kAXErrorIllegalArgument marks the cached XCUIApplication target handle suspect. The runner fails closed for degraded interactive snapshots, clears the cached target, and lets the next command reacquire the app through normal activation.
• Resolution disclosure (ADR 0012 decision 2): additive resolution field on press/click/fill/longpress responses discloses how the acting path resolved its target — runtime/unique or runtime/disambiguated (with matchCount/winnerDiagnostic/tiebreak/up-to-5 alternatives) on the daemon tree, ref/exact for a resolved @ref (runtime-ref and native-ref), ref/label-fallback when runtime-ref recovered a stale @ref via its recorded trailing label, or direct-ios/not-observed on the XCTest fast path; absent entirely on the coordinate path and on dispatches whose runner actually executed the maestro non-hittable coordinate fallback (permission alone keeps the direct path's not-observed). Pre-action diagnostics only: winnerDiagnostic/alternatives entries carry an opaque, non-@ diagnosticRef that is never ref-issued, never MCP-pinned, and cannot be reused as an @ref target — a fresh snapshot/find is required before acting on an alternative.

Architecture (perfect-shape refactor, completed 2026-07)

ADR 0011 (interaction guarantee contract) is the interaction-semantics counterpart of ADR 0008's registry thesis: the dispatch-path × guarantee matrix is declared once in src/contracts/interaction-guarantees.ts, completeness is type-enforced, honesty and coverage are gate-enforced, and cross-language rules are pinned by golden parity tables. New dispatch paths and guarantees are whole-matrix decisions, not local edits.

The perfect-shape refactor is complete and merged. Its end-state:

• Two derivation registries. One CommandDescriptor per command (src/core/command-descriptor/registry.ts) is the single declaration site from which the public/internal/local command catalog, capability matrix, daemon command registry, batch allowlist, timeout policy, MCP exposure list, capability-checked CLI command list, post-action observation traits, and platform dispatch command set are derived by parity-tested projection. Command families still own surface metadata/CLI schema in src/commands/**, but descriptor/catalog coherence guards prevent surface names from drifting; system command facets now project their simple Node client command methods. Closed public Node-client result contracts are narrowed through CommandResultMap; action/backend-dependent methods remain explicitly broad until their public response projections are reconciled. See Node client result types. One PlatformPlugin per platform family (src/core/platform-plugin/) stops core/daemon from branching on platform, with the Apple plugin the first instance. See ADR 0008.
• Typed result spine. Per-command typed results replaced the ad-hoc Record-typed returns across the daemon/dispatch path; errors gained machine-readable retriable/supportedOn signals on DaemonError (#939). Error-system conventions live in ADR 0010.
• Apple platform model. Internally Platform is apple (plus android/linux/web) with an appleOs discriminant (ios | ipados | tvos | watchos | visionos | macos); the shared Apple engine lives under src/platforms/apple/core/ with per-OS leaves under src/platforms/apple/os/<os>/. The public wire stays non-breaking: PUBLIC_PLATFORMS (src/kernel/device.ts) still emits ios/macos leaf output. See ADR 0009.
• Folder DAG + layering lint. scripts/layering/check.ts enforces two different scopes in CI. GLOBALLY, across every production source file, it enforces the R1-R3 move rules (kernel-sink, commands-floor, platforms-seam) and rejects all production static value-import cycles. Separately, it ranks an explicit target spine — as rank groups, lowest (kernel sink) to highest, where A ◄ B means B may not be outranked by A (the back-edge order the gate rejects), NOT that every displayed import exists: kernel ◄ { contracts, request, selectors, platforms } ◄ core ◄ { commands, cli-schema } ◄ { client, daemon-server } ◄ daemon-client ◄ cli — and rejects every back-edge within it. Root entrypoints and peripheral zones (mcp, compat, remote, metro, replay, recording, snapshot, screenshot-diff, cloud-webdriver, sdk, utils) are deliberately unranked (UNRANKED_ZONES in scripts/layering/model.ts): they still obey R1-R4, but the gate asserts no total back-edge order over them. It is not a claim that every folder is arranged in one DAG. model.test.ts guards that no new zone escapes this classification silently.
• Agent-cost. Responses carry a cost block and MCP outputSchema, rendered through a leveled ResponseView.

Deferred

The refactor is substantively done; these follow-ups are intentionally deferred, not lost:

• Dynamic Node-client results — interactions, observability, alert, React Native overlay, and settings remain broad until their action/backend-specific payloads have accurate public projections. See Node client result types.
• Legacy alias drops — ~175 LOC of legacy aliases/barrels remain, gated to the next major.

Selector Capture Reliability Contract

Selector capture is allowed to optimize transport, helper reuse, and polling, but it must preserve the observable freshness and failure semantics below before any runtime refactor.

• Direct iOS selector queries are a narrow fast path only: iOS, simple one-term id/label/text/value selectors, and never while postGestureStabilization is pending. A direct miss may fall back to the snapshot selector path, but ambiguous matches and runner errors must surface instead of silently falling back. get text uses direct native selectors only for simple id selectors because label/text/value reads need snapshot disambiguation.
• Regular selector reads remain capture-backed. @ref reads resolve against stored session snapshots; selector get/is/find/wait capture through the backend. find and wait polling must bypass the 750 ms snapshot cache. The cache is also bypassed while Android freshness recovery or post-gesture stabilization is active.
• Sparse snapshot quality verdicts are observable failures. Sparse captures must not replace session.snapshot, and selector routes should report the sparse verdict instead of treating a root-only or sparse tree as an empty UI.
• iOS sparse and AX failures are not proof of empty UI. Regular visible snapshots can recover through the capture plan; raw and strict paths preserve failure. runnerFatal invalidates the cached target and must never refresh healthy mutation recency.
• Android helper reuse must not become snapshot result caching. Freshness is short lived, marked only after navigation-sensitive actions, compared against broad route-safe baselines, and not learned from scoped, depth-limited, interactive, or ref-refresh snapshots.
• Pending interaction outcome retry runs before post-gesture stabilization. Android freshness then composes when needed. Stabilization applies after swipe, scroll, gesture, or an explicit flag, and disables direct iOS selector shortcuts while pending.
• setSessionSnapshot is the centralized session snapshot mutation path. Sparse captures do not write back, and empty @ref-scoped snapshot output must not replace the stored session snapshot.
• Maestro target matching remains snapshot-based, fresh, and policy-rich. Native selector simplification must not erase Maestro regex/string selector behavior, visibility filtering, ranking, fuzzy fallback, visible-context preference, Android duplicate handling, tab-strip inference, or assertion/wait semantics.

Evidence: ADR 0002, ADR 0004, ADR 0005, Maestro compatibility debt map, find.test.ts, snapshot-handler.test.ts, snapshot-scoped-refs.test.ts, runtime-targets.test.ts, and android-test-suite.test.ts.

Testing Principles

• Provider-backed integration scenarios should exercise the public daemon path whenever practical.
• Prefer the in-process provider scenario harness for broad scenarios; keep HTTP contract tests narrow and transport-specific.
• Provider seams sit below platform modules so integration tests still cover platform command translation.
• Provider transcripts are for exact external command contracts.
• Scenario transcripts are for broad, user-rooted workflows that should replace mocked handler unit tests.
• Unit tests stay for pure logic, parser matrices, selector matching, capabilities, and important edge cases.