This is a public npm package in Tutti's fixed @tutti-os/* release cohort. External products install the same exact cohort version as their other Tutti dependencies:

pnpm add --save-exact @tutti-os/agent-session-replay-runner@<version>

import {
  createReplayProductPorts,
  runReplayCassetteBatch
} from "@tutti-os/agent-session-replay-runner";

Shared Go Cassette / Replay contracts stay in packages/agent/session-replay. This package owns Node orchestration helpers that must stay isomorphic across products.

Bundled contracts

The published tarball carries the canonical cross-language contracts from the Go core at these public subpaths:

@tutti-os/agent-session-replay-runner/cassette-policy.json
@tutti-os/agent-session-replay-runner/activity-contract.json

Consumers resolve those package subpaths and read the files from the installed package. They do not locate or read a Tutti source checkout.

What products must supply

Desktop / Electron launch + ports (CDP, daemon listener, control path).
Room / Workspace / shared-agent product surfaces (TSH Room bootstrap, Tutti workspace rail, ui-drive product adapters).
A ReplayProductPorts object via createReplayProductPorts(...) for path scope, transport command dialect, and session-observation mode.

Vertical slice (current)

Extracted and wired from both runners:

cassette policy loader (loadCassettePolicy) — path-agnostic bytes + shape
managed replay log prefixes + control router document helper
serial async queue
checkpoint plan load / validate (schemaVersion injected by product)
stimulus idle precondition + duplicate engine-send guard + replayStimulusRequest (scope segment: workspaces / rooms)
recording helpers (resolveRecordScenarioProject, binding verify, assertForbiddenPathAbsent, seedRecordingUserProject)
playback sub-helpers (activity clock, provider cursor math, status/failure log routing, submit-idle gate, retryable stimulus statuses, registration validation, hydration/session-terminal diagnostics, transport health GET)
turn freshness / pending-interaction identity helpers + renderer snapshot collapse (activityTurnFromRendererSnapshot)
evidence helpers (checkpoint PNG path, clip/label, settle predicates)
managed Desktop shutdown binder (bindManagedReplayShutdown; products inject stopDesktop)
wait diagnostics (configureReplayWaitDiagnostics, pollUntilReady, compact/format helpers) — no CDP/Room embedding
ui-drive scenario shell (loadUiScenario, runUiDriveScenario, checkpoint screenshot/plan helpers) — products inject prepare/launch/surface ports
createReplayPlaybackController / createReplayTurnIdentityTracker / runReplayCassetteBatch / replayStimuli / waitForSessionIdle — parameterized by ReplayProductPorts (no product-named forks); a cassette wave preserves the first failure as the shared abort cause and emits one terminal outcome per cassette
cassette verify / parse / blobs / portable activity payload / turn-identity plan (createCassetteHelpers, verifyCassette, parseActivityEvents, materializeReplayWorkspaceBlobs, …) — products bind policy + optional ports (TSH shared-agent prerequisite fork, Tutti realpath canonicalization)

Product ports (dialect injection)

Build ports with createReplayProductPorts. Command name helpers:

Concern	Typical Tutti wiring	Typical Room/TSH wiring
Timing / cursor commands	`KEBAB_REPLAY_TRANSPORT_COMMANDS`	`CAMEL_REPLAY_TRANSPORT_COMMANDS`
Timing wire values	`encodeKebabTimingModeValue`	`encodeCamelTimingModeValue`
Playback state	`normalizePlaybackStateRequireTimingMode`	`normalizePlaybackStateDeriveTimingMode`
HTTP scope	`workspaces`	`rooms`
Session GET	no `/state`	`agentSessionStateSuffix: true`
Observation	`sessionObservation: "canonical"`	`"lean-activity"` (+ baselines)
Session watch	off	`watchSessionsDuringPlayback: true`

Products keep a thin wrapper that injects their ports; shared modules must not hardcode product names.

Still product-local:

runtime / ui-drive / Room bootstrap / Electron launch / CDP evaluate waits
TSH shared-agent target rewrite + Room project-binding helpers that sit beside the shared cassette kernel ports