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Briefcase AI

Persist & Replay

Install

Install with storage and replay
pip install "briefcase-ai[storage,replay]"

Live observability (@capture + observe()) only needs the base package. Persistence and replay import briefcase.storage and briefcase.replay, which are gated behind extras — see Installation.

Persist a snapshot

Build a typed DecisionSnapshot, then save it with a storage backend. SqliteBackend.in_memory() is fine for a notebook; use a file path to keep decisions across runs.

  1. Build and save a DecisionSnapshot

    from briefcase import (
        DecisionSnapshot,
        Input,
        ModelParameters,
        Output,
        init,
    )
    from briefcase.storage import SqliteBackend
    

    init()  # start the native runtime
    

    decision = DecisionSnapshot("classify_ticket")
    decision.add_input(Input("ticket_text", "My invoice is wrong", "string"))
    

    params = ModelParameters("gpt-4o-mini")
    params.with_provider("openai")
    params.with_parameter("temperature", 0.0)
    decision.with_model_parameters(params)
    

    output = Output("category", "billing", "string")
    output.with_confidence(0.93)
    decision.add_output(output)
    decision.with_execution_time(12.0)
    

    backend = SqliteBackend.in_memory()  # or SqliteBackend("./decisions.db")
    decision_id = backend.save_decision(decision)
    print(f"Recorded decision {decision_id}")

  2. Replay and compare

    from briefcase.replay import ReplayEngine
    

    engine = ReplayEngine(backend)
    result = engine.replay(decision_id, "strict")
    

    print("status:", result.status)
    print("outputs match:", result.outputs_match)
    print("execution time (ms):", result.execution_time_ms)

  3. Verify the result

    ReplayResult exposes .status, .outputs_match, .replay_output, .execution_time_ms, and .policy_violations. Valid replay modes are "strict" and "tolerant".

What’s next

You now have a reloadable, replayable record. Continue into governance and audit when you need controls before the action or proof after the fact.

Core Concepts Inputs, outputs, parameters, and how snapshots group decisions.
Storage Adapters Choose where persistent decisions live.
Deterministic Replay Go deeper on replay modes and comparison.
Audit a Decision Seal evidence, policy, and outcome into a verifiable bundle.