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Zep
AI Agents Guide

What Is a Context Lake?

A Context Lake is the infrastructure that implements agent memory at enterprise scale — a governed system of context graphs. The data-lake parallel, explained.

Agent Runtime

LangChain·LlamaIndex·CrewAI·Google ADK·custom

Any agent framework — or none. The Context Lake is invoked through a single SDK.

Ingestion

chat·JSON·documents·app events

Raw signal arrives from any source the agent touches.

Context Assembly

context blocks·templates·token-efficient

Relevant context is assembled on demand into token-efficient blocks.

entity extraction·relationships·ontology·invalidation

Signal becomes a temporal context graph as new facts arrive and stale ones are invalidated.

Retrieval

sub-200ms·auto-optimized·provenance-linked·policy-filtered

Selects what's relevant and what adds the most information within the token budget.

Governance

ABAC·multi-tenant isolation·customer key encryption·retention policies·audit·provenance

Native to the substrate, not a layer bolted on. Every read and write is policy-gated for access and provenance; retention runs across the data lifecycle.

Context Graph Engine

entities·facts & edges·decision traces·episodes

Temporal context graph with provenance — sub-200ms retrieval at scale.

Key takeaways

  • A Context Lake is the infrastructure that implements agent memory at enterprise scale — a governed system of context graphs.
  • It's the data-lake pattern applied to agent context: complementary, not competing — different data and consumers, the same governance rigor.
  • Powered by the Context Graph Engine with Graphiti; sub-200ms p95 retrieval across millions of graphs. S&P Global Market Intelligence named Zep a likely de facto partner in the enterprise agent stack (coverage).

A Context Lake is the infrastructure that implements agent memory at enterprise scale — a governed system of context graphs that manages, governs, and serves everything AI agents need to know. It is to agent memory what the data lake is to analytics: a single, governed substrate that holds many sources and serves many consumers. Zep is the Context Lake for AI agents.

The problem it solves

Giving one agent memory is straightforward. Running memory for an enterprise — millions of users, hundreds of agents, dozens of data sources, all under access control, retention, and audit requirements — is an infrastructure problem. Bolting memory onto each agent produces silos, inconsistent governance, and no way to audit what an agent knew or why it acted. The Context Lake solves this the way the data lake solved analytics sprawl: one governed system, many graphs, served as a platform.

The data-lake parallel

The analogy is deliberate and precise — and complementary, not competing:

Your Data LakeContext Lake
Data

Structured, quantitative

Tables, transactions, logs, metrics.

Unstructured, qualitative

Conversations, documents, events, decisions.

Query model

SQL, batch analytics

Optimized for aggregation and retrospective analysis.

Graph traversal, semantic

Temporal context graphs with entity-aware retrieval.

Latency

Seconds-to-minutes

Batch jobs, scheduled pipelines, dashboard refresh.

Sub-200ms retrieval

Real-time context at agent inference speed.

Consumers

Dashboards & ML

BI tools, data scientists, reporting pipelines.

Agents & assistants

LLM-powered applications that need memory and context.

Governance

Row & column ACLs

Table-level permissions, role-based access.

Entity-level ABAC

Attribute-based policies, retention rules, full audit trail.

Data lakeContext Lake
HoldsRaw + processed business dataContext graphs (what agents know)
ConsumersBI tools, analysts, ML pipelinesAI agents
Access patternBatch + queryMillisecond retrieval at run time
Shared traitGoverned at the substrateGoverned at the substrate

A Context Lake doesn't replace your data lake. They hold different data for different consumers with different access patterns — but the same governance rigor. The data lake feeds analytics; the Context Lake feeds agents.

What a Context Lake is made of

  • Context graphs — temporal, bi-temporal graphs (one per user, team, or project) that track entities, relationships, and facts, with provenance and validity over time.
  • The Context Graph Engine — the runtime that persists and serves millions of these graphs with sub-200ms p95 retrieval regardless of graph size or count, using a hot-graph memory strategy (active graphs in memory, the rest snapshotted to cheap object storage).
  • Graphiti — the open-source library that constructs the context graphs from inputs. Graphiti runs on top of the Context Graph Engine when scaled with Zep.
  • Governance in the substrate — attribute-based access control (ABAC), retention policies with legal hold, and audit logging apply across every graph and every query, not bolted on per agent.

How it manages, governs, and serves

  • Manages: ingests any source (chat, business data, documents), constructs and continuously updates context graphs, and invalidates facts as they change.
  • Governs: enforces who can access what context, how long data is retained, and produces an audit trail of every request and policy decision — with provenance from every fact back to its source.
  • Serves: returns relevant, token-efficient context to any agent in milliseconds, across millions of graphs, in any deployment model (managed cloud, your own keys, or inside your VPC).

Who it's for

Engineering and AI leaders building agents at production scale — especially in regulated or data-sensitive environments (financial services, healthcare, enterprise support) where governance, provenance, and deployment control aren't optional. S&P Global Market Intelligence (451 Research) initiated coverage on Zep as a likely de facto partner in the enterprise agent stack, citing exactly this enterprise-plus-temporal-graph differentiation.


Related: What is agent memory? · Context Graph Engine · Graphiti · Enterprise & deployment

Frequently asked questions

Is a Context Lake the same as a data lake?

No, and it doesn't replace one. A data lake serves analytics; a Context Lake serves agents. Different data, different consumers, different access patterns — same governance rigor. They're complementary.

Is a Context Lake just a vector database or a knowledge graph?

No. It's a governed system that manages many temporal context graphs and serves them at scale with millisecond retrieval, access control, retention, and audit. A single vector store or graph database is a component, not the governed substrate.

How is a Context Lake different from agent memory?

Agent memory is the category — everything an agent knows over time. A Context Lake is the infrastructure that implements agent memory at enterprise scale.

What powers Zep's Context Lake?

The Context Graph Engine (the proprietary runtime) with Graphiti (open source) constructing the graphs on top of it.