callstack__agent-device/CONTEXT.md

Agent Device Domain Context

Durable vocabulary for this repo. Use these names in code, tests, issue titles, and architecture notes rather than coining parallel ones. You rarely need the whole file — jump to the section your task touches:

• Sessions, targets, devices
• Command surface & routing
• Interaction, refs, and guarantees
• Gestures & touch
• Snapshots & capture
• Recording & replay
• Maestro compatibility
• Providers, cloud, and the test harness
• Architecture — the two-registry end state
• Selector capture reliability contract — invariants any capture refactor must preserve
• Testing principles

Terms

Sessions, targets, devices

• 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.
• 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.
• iOS physical-device control: Apple-local module selected from discovery evidence. CoreDevice devices retain the devicectl controller; devices found only by xctrace use the XCTest controller for readiness, app activation/termination, and cable-bound usbmux runner transport without claiming unsupported app inventory or installation capabilities.
• 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 & routing

• 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.
• 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.

Interaction, refs, and guarantees

• 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.
• 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.
• 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.
• 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.
• 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.
• Ref frame (ADR 0014): the session's single authorization namespace for mutation @refs, kept separate from the latest operational observation (session.snapshot). It owns a frozen epoch (the refsGeneration the client received), an immutable source tree, a lifecycle state (active/expired), and an issuance scope (all for a complete snapshot, or the bounded set of ref bodies a partial publication emitted). Owned solely by src/daemon/ref-frame.ts. A complete snapshot activates an all frame; find/settled diff/replay divergence activate a bounded partial frame that supersedes the prior one; internal read captures never activate or reindex it.
• Frame expiry seam (ADR 0014): every mutating leaf calls expireRefFrame synchronously, immediately before the device op that may change element identity (after all pre-action guards), so a post-dispatch failure still leaves the frame expired — there is no success-only rollback. Ref resolution binds @eN against the frame's source tree, so an Android freshness (or any read-only) capture cannot retarget an admitted ref by positional coincidence; a fresh capture's coordinates are adopted only when its node's local identity matches.
• Mutation admission (ADR 0014): a ref mutation is admitted only against an active frame whose epoch and issuance scope authorize the ref (admitRefMutation, order-sensitive reasons ref_frame_expired → ref_generation_mismatch → plain_ref_requires_complete_frame → ref_not_issued). Rejections carry details.reason and name the lifetime failure. A ref-oriented sequence that performs several mutations must re-observe (snapshot), consume an honestly issued settled ref in pinned form, or use selectors. Read-only ref consumers stay fail-open with a staleness warning while the frame retains the ref's evidence.
• 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.
• 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.

Gestures & touch

• 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.

Snapshots & capture

• 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.
• iOS WebView semantic presentation: the interactive snapshot projection that recognizes XCTest's typed WebView root and WebKit's Other -> StaticText wrapper pairs. It keeps raw diagnostics unchanged, presents ordinary wrapper text as StaticText, and presents wrappers carrying WebKit's numeric HTML heading level as Heading.
• 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.

Recording & replay

• Script recording: opt-in session mode armed before actions so a persisted .ad can carry portable action inputs and recording-time target identity evidence. It is distinct from screen/video recording.
• Recorded input parameterization: explicit fill authoring contract that sends literal text only to the live interaction while the recorder stores ${VAR} before any durable recording/event/publication boundary. The caller owns the uppercase variable name; no selector or field-name heuristic infers sensitivity. Replay resolves the placeholder immediately before dispatch and preserves the authored placeholder if that run is recorded again.
• Open-to-destination script: self-contained .ad script with exactly one initial open, a destination guard after its last app-state mutation, no close, and an app session left active for subsequent work. Avoid: replay (artifact noun), fragment (reserved for lifecycle-free composition), partial script.
• Destination guard: portable selector-targeted wait near the end of an open-to-destination script that confirms a landmark on the ready destination screen before replay hands the live session to its caller.
• 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.

Maestro compatibility

• Maestro program: source-preserving typed representation of supported Maestro YAML. It is interpreted directly through the compatibility runtime port and never lowered through generic replay action strings. See ADR 0015.
• Maestro observation generation: explicit compatibility-engine state identifying evidence captured since the most recent mutation. Queries may share semantic evidence within one generation; every mutation attempt invalidates it before dispatch. Interaction geometry is action-local: unique exact iOS selectors resolve and tap atomically in XCTest, while coordinate dispatch uses a fresh target snapshot. Rectangles are never shared across command boundaries.

Providers, cloud, and the test harness

• Provider: request-scoped adapter interface for external device, runner, or host tool execution.
• Provider-backed integration scenario: device-free integration test that runs the real daemon request path and replaces only external device 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.

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/vega/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.
• Vega platform model. Initial Vega OS support is deliberately VVD-only: discovery returns VirtualDevice, and platform capability admission rejects physical Fire TV devices until durable hardware evidence validates discovery, lifecycle, and the complete remote-control contract. Vega capture, selector, inventory, install, logging, and performance backends remain separate follow-up surfaces.
• Folder DAG + layering lint. scripts/layering/check.ts enforces five rules across four 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. R1-R3 are declared as data in scripts/layering/zone-policy.ts (ZONE_POLICIES): which zones a boundary governs, which import kinds it tolerates, and which path prefixes are its declared seam. A fourth zone boundary is a table entry, not a fourth predicate. zone-policy.test.ts asserts each boundary fires and each exemption holds — necessary because the tree is clean, so a rule that stopped matching would look exactly like a rule being obeyed. 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, utils, replay, recording, snapshot, screenshot-diff, cloud-webdriver } ◄ { core, providers } ◄ { commands, cli-schema, mcp } ◄ { client, daemon-server, compat, remote, metro, sdk } ◄ daemon-client ◄ cli — and rejects every back-edge within it. Only (root) is unranked (UNRANKED_ZONES in scripts/layering/model.ts): it holds the entrypoints and the composition roots that wire the command surface into the daemon, and R2 forbids daemon/ from importing commands/, so those files sit outside the spine by construction. The satellite zones used to be unranked too, on the grounds that ranking them would invent an order the architecture had not committed to; once utils joined the spine and (root) was emptied of shared contracts, every one of them turned out to have a consistent rank already. model.test.ts guards that no new zone escapes this classification silently. Thirdly, R6 ratchets the SAME inversion measured over TYPE-ONLY edges, which R5 ignores by design: a type-only import is free at runtime, but "zone A is declared in terms of zone B" is still a boundary claim, and ranking type edges surfaced 61 inversions the gate had never seen. TYPE_INVERSION_BASELINE in check.ts holds the remaining pairs with their counts; the numbers may only shrink, and a new pair fails outright. Down to 7, and each is a deliberate position rather than a misplaced declaration: 4 are AgentDeviceClient used as an opaque handle (the facade is built from commands/'s own projection registry, so moving it down is a design call about where that registry belongs, not a file move), and 3 are the ADR 0003 daemon descriptor, whose route type is keyof typeof DAEMON_ROUTE_HANDLERS — derived from what the server actually implements. Both are explained at the baseline.
• SessionState ownership (R7). SessionStore.get() returns the live record out of a private Map and set() re-puts the same reference, so any session.<field> = … in the daemon is a durable write to store-owned state — persistence depends on aliasing, not on an API call. That is workable while each field has an owner that keeps its invariants, so SESSION_STATE_FIELD_OWNERS (scripts/layering/session-state.ts) records them and the gate stops the set from growing quietly: a new field must declare an owner, a foreign write fails with the owner to call instead, and an owner that stops writing must be removed. The classification is exhaustive — every field is either in that table or in STORE_OWNED_SESSION_STATE_FIELDS, the positive claim "the store establishes this and nothing mutates it later". Without that parity a new field with no direct write would satisfy the gate by being invisible to it, and R7 would silently stop covering part of the type it covers. A direct write to a store-established field fails, naming both remedies. Detection follows session records through aliased bindings (nextSession, provisionalSession, completedSession), not just a local named session: matching the literal name is what let three genuine foreign writes sit unreported. Since there is no type information in the gate, the binding test is a name test paired with the declared-field filter — a provider or runner session only registers if it also writes a field SessionState owns, and the remedy is then the same. ADR 0014's ref frame and the snapshot lineage are the worked examples: the frame's four fields moved together across two modules until activateRefFrame took the transition, and snapshotScopeSource + snapshotGeneration were assigned in snapshot-runtime.ts until setSnapshotLineage took theirs.
• Type-cycle growth (R9). R4 keeps the VALUE import graph acyclic, so every remaining cycle is created by type-only imports — free at runtime, invisible to R5/R6, and the largest single obstacle to reading a subsystem in isolation: inside a strongly-connected component of 102 files, no file has a self-contained slice. TYPE_CYCLE_BASELINE in check.ts ratchets it for growth only, deliberately unlike R6: reducing it is a real refactor rather than a file move, so a hard equality would turn every unrelated improvement into a baseline edit. A shrunk tree is reported in the success line instead of failing. Hubs by in-component dependents: runtime-contract.ts (25), commands/runtime-types.ts (21), backend.ts (15), commands/runtime-common.ts (12).
• Zero-dep CI jobs (R8). Some jobs run scripts straight from a checkout with install-deps: false, so they have no node_modules. Nothing local can feel that constraint — every dev machine has node_modules sitting right there — so a script grows a package import, passes locally, and fails the runner on the resolve. R8 reads the zero-dep job list out of .github/workflows/ (declaring a job zero-dep is what puts it under the rule; there is no second list to update), walks each job's entry scripts and their whole relative-import closure, and requires every specifier to be a Node builtin or another repo file. A zero-dep job whose entry scripts the scan cannot identify fails too, so the rule cannot be escaped by changing how the job invokes them. Specifiers come from oxc-parser's module record rather than a line scan, because these closures include --test files whose fixtures legitimately contain import syntax inside strings.
• Agent-cost. Responses carry a cost block and MCP outputSchema, rendered through a leveled ResponseView.

Principles and their gates

The architecture rules this repo runs on are Clean-Architecture-shaped. Some are fully gate-enforced, some carry an open ledger that only shrinks, and some are norms with local evidence but no gate yet — each bullet below says which. When judging a design change, argue from the rule; when landing it, satisfy the gate where one exists.

• Dependency Rule (source dependencies point toward policy; details depend on abstractions). Gate: layering R1–R3 import direction plus the ranked spine's no-back-edges check (scripts/layering/check.ts). #1405's "shared contracts below their consumers" is dependency inversion stated as a merge gate. Ledger: TYPE_INVERSION_BASELINE — type-only inversions where types still flow the wrong way; the ratchet only tightens, and the long-term target is zero.
• Acyclic components. Gate: R4 bans value-import cycles globally. Type-only and dynamic-import cycles are deliberately tolerated by the gate; a report surfacing them as data is proposed in #1410 (the analysis half of the graph tooling, kept after the #1409 viewer was rejected) and is not landed yet.
• Policy × detail boundaries on demonstrated axes of change. The two registries are the two demonstrated axes: CommandDescriptor (what the system does) × PlatformPlugin (how a device does it), ADR 0008/0009. Boundary-crossing enforcement is narrower than the principle: the apple-platform leak guard (publicPlatformString, provider-integration suite) gates one specific DTO class — internal apple never reaching serialized public output — and the injectable Apple runner transport (runnerProvider, #1389) is one adopted seam, not a rule covering every boundary. Wider DTO/seam coverage is direction, not current enforcement.
• Information hiding. Gate: R7 — every SessionState field is classified and every write must occur inside its declared owner. Encapsulation of the one shared mutable object, enforced per-field. This covers SessionState; other shared state has no equivalent gate today.
• Boundaries are earned, not speculative. Norm with local evidence, not a gate: the platform descriptor layer (~600 LOC of boundary nobody needed) was deleted, and the depgraph viewer (#1409) was closed unmerged. A new abstraction layer needs a demonstrated second consumer or axis of change. The one gated slice of this norm is tests: CI forbids test-only DI seams — a missing seam gets added as a real one or not at all.
• Tests couple to stable interfaces. Norm (see Testing Principles) backed by the test-only-DI-seam gate above; broader test-strength enforcement is planned, not present — tracked under #1412.
• Component metrics are observatory data, never gates. Instability/abstractness per zone is a proposal (#1423, building on #1410's graph model) to locate concrete, high-fan-in modules worth pinning harder — explicitly never a CI threshold.

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. @refs resolve against the authorized ref frame's source tree (ADR 0014), not whatever now sits at that index in a newer observation; 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 and policy-owned. Coordinate dispatch always uses a fresh target snapshot. A unique exact iOS match may instead reuse bound same-generation semantic evidence and dispatch through XCTest's atomic selector tap; structured live-selector failures return to fresh Maestro resolution. This optimization must not erase Maestro regex/string selector behavior, visibility filtering, provider-order first-match selection, explicit index selection, or assertion/wait semantics. Provider normalization belongs below the compatibility layer. Plain text is exact and regex-aware; do not add substring/fuzzy recovery, synthetic geometry, or hierarchy-shape heuristics that change authored selector meaning.

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-typed.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.

Gate selection, speed rules, and shared fixtures live in docs/agents/testing.md.