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Migrate

Migrate from LangMem

LangMem is LangChain's in-process memory library, typically backed by a local vector store or an in-memory store. This guide covers the concept mapping and migration path to SurrealDB Agent Memory.

LangMem conceptSurrealDB Agent Memory equivalentNotes
NamespaceScope + ContextSurrealDB Agent Memory uses scope tags within a named Context
Memory (document)Entities + attributesSurrealDB Agent Memory extracts structure; LangMem stores flat text
put_memories()remember()Write path is similar; extraction differs
search_memory()recall()SurrealDB Agent Memory adds graph-density reranking
get_memories()profile()Returns structured snapshot
Memory type (semantic, episodic, procedural)Memory category (knowledge, context, instructions)Categories have different volatility and expiry
delete_memories()forget()Query-driven; POST /scopes/forget erases a whole subtree
InMemoryStoreEmbedded SurrealDB Agent Memory (in-process SurrealDB)See the embedded deployment guide
from langgraph.store.memory import InMemoryStore
from langmem import create_memory_store_manager

store = InMemoryStore(
    index={"dims": 1536, "embed": embeddings}
)
memory = create_memory_store_manager(
    "openai/gpt-4o",
    namespace=("user", "alice"),
    store=store,
)

await memory.aput(
    [{"content": "Alice prefers concise, technical answers."}]
)
results = await memory.asearch("communication style")
from surrealdb.memory import AsyncMemory

client = AsyncMemory(
    context="dev",
    endpoint="https://spectron.example.com",
    api_key="sk-...",
)

await client.remember(
    "Alice prefers concise, technical answers.",
    scopes=["user/alice"],
)
results = await client.recall("communication style", k=5, lens=["user/alice"])
for hit in results.hits:
    print(hit.text)

Persistence: LangMem with InMemoryStore loses all memory when the process restarts. SurrealDB Agent Memory is durable by default - all memory lives in SurrealDB and survives restarts, deployments, and crashes.

Structured extraction: LangMem stores memories as text documents. SurrealDB Agent Memory extracts structured entities, attributes, and relations. "Alice prefers concise answers" becomes an entity Person/alice with attribute communication_style = "concise, technical" - queryable and updatable as structured data.

Conflict handling: LangMem stores all memories and relies on the retrieval layer to resolve conflicts via recency ranking. SurrealDB Agent Memory detects contradictions and supersedes old attribute values, maintaining a correct, single current value with a history chain.

Namespace vs scope: LangMem uses a tuple namespace ("user", "alice"). SurrealDB Agent Memory uses hierarchical slash paths like ["user/alice"]. For single-clause scopes, org-wide queries surface org-tagged memory while hiding user-specific records - see Contexts and scope.

Categorisation: SurrealDB Agent Memory's categories map loosely to LangMem memory types:

  • LangMem semanticknowledge (facts, preferences)

  • LangMem episodiccontext (recent, auto-expiring events)

  • LangMem proceduralinstructions (behavioural directives)

SurrealDB Agent Memory ships a LangChain memory adapter (planned). Until it is released, use the SDK directly and inject the formatted context into your chain or graph:

from langchain_core.messages import SystemMessage
from surrealdb.memory import AsyncMemory

client = AsyncMemory(context="dev", endpoint="...", api_key="...")

class AgentMemoryStore:
    def __init__(self, client: AsyncMemory, scope: list[str]):
        self.client = client
        self.scope = scope

    async def load_context(self, query: str) -> str:
        results = await self.client.recall(query, k=5, lens=self.scope)
        return "\n".join(hit.text for hit in results.hits)

    async def save_turn(self, role: str, content: str):
        await self.client.remember(f"{role}: {content}", scopes=self.scope)

# Usage in a LangGraph node
async def agent_node(state, memory: AgentMemoryStore):
    context = await memory.load_context(state["messages"][-1].content)
    messages = [
        SystemMessage(content=f"Memory:\n{context}"),
        *state["messages"],
    ]
    response = await llm.ainvoke(messages)
    await memory.save_turn("assistant", response.content)
    return {"messages": [response]}

If you are using the older LangChain ConversationBufferMemory or similar in-context memory, migration is straightforward: replace the buffer with SurrealDB Agent Memory sessions. Instead of passing the full conversation history as context (which grows without bound), pass a recalled summary from SurrealDB Agent Memory.

# Before: buffer-based
memory = ConversationBufferMemory()
chain = ConversationChain(llm=llm, memory=memory)

# After: Memory-based
async with client.sessions.create(scopes=[f"user/{user_id}"]) as session:
    # At turn start, recall relevant context
    context = await client.recall(user_message, k=5)

    # Pass context as part of the system prompt instead of full history
    response = await llm.ainvoke([
        SystemMessage(content=f"Relevant context:\n{context['hits']}"),
        HumanMessage(content=user_message),
    ])

    # Store the turn
    await client.remember(user_message, session_id=session.id, role="user")
    await client.remember(response.content, session_id=session.id, role="assistant")

This approach scales indefinitely - context window size is bounded by k on recall, not by conversation length.

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