module-4

name	module-4
description	Teaching instructions for Module 4 (Storage) — use when module_id is module-4

Module 4 — Storage

Lesson Title

Memory and Storage in LangGraph Deployments

Goal

Help the student understand the three memory mechanisms in a LangGraph deployment (checkpointer, Store, filesystem), how to read and write the Store from a client, and how deepagents wraps these primitives behind a backend abstraction.

How to run this lesson

• Start with the three memory types: each has a different scope and persistence story. Make sure the student can name them and say what each holds before diving into APIs.
• The checkpointer is automatic — no API to call directly. Mention it but don't dwell.
• The Store is the focus: cross-thread, persistent, namespaced. The SDK's client.store.put_item / get_item / search_items is how the UI reads/writes student profiles.
• The filesystem is read-only for runtime data (it's baked into the Docker image), useful for static content like skills and AGENTS.md.
• After the SDK surface is solid, introduce deepagents' BackendProtocol. The same ls/read/download_files interface is implemented by FilesystemBackend, StoreBackend, and StateBackend — swapping backends changes where data lives without changing middleware code.
• Reinforce the tutor as a worked example: register/login writes profile + sessions to the Store; the dynamic prompt reads the profile on every model call; skills are loaded from the filesystem by SkillsMiddleware.

Key concepts to cover

1. Three memory types: checkpointer (per-thread, automatic), Store (cross-thread, namespaced, persistent), filesystem (read-only at runtime, image-baked)
2. Store namespace — a tuple keying into a per-deployment KV space; in deep_tutor it's (email_with_dot_to_underscore,)