Zep Review (2026): Pricing, Features & Honest Verdict

TLDR

Zep is a memory layer for AI agents that stores context as a temporal knowledge graph, so your agent knows not just a fact but when it was true. We found the retrieval fast and the governance serious, though credits add up. Best for: teams building production agents. Price: Free plan; Flex from $125/mo. Rating: 7.8/10.

What is Zep?

Zep is a context engineering platform that gives AI agents enterprise-grade memory. Instead of dumping an entire chat history into every prompt, Zep builds a temporal knowledge graph from chat messages, user interactions, and structured business data. Your agent queries that graph and gets back only the facts that matter, with retrieval times under 200 milliseconds regardless of how large the graph grows.

The company was founded in 2023 by Daniel Chalef. Zep leans hard into the production-agent crowd: it advertises SOC 2 compliance, access controls, retention policies, and audit trails baked in at the infrastructure level. That positioning sets it apart from lighter memory tools. Zep is not trying to be a hobbyist add-on. It wants to be the memory backbone for agents that real companies put in front of real users. The customer list reflects that, spanning Fortune 500 technology firms, AWS, and Samsung alongside fast-growing startups.

Why does this matter now? Agents are moving from demos into production, and the moment they do, memory becomes the hard problem. A chatbot that forgets what a user said two turns ago is a toy. An agent that remembers a customer’s history, knows which facts are still current, and can prove where each fact came from is something a business can trust. Zep is built for that second category, and the underlying engine, Graphiti, is the piece that makes the temporal graph work.

What Are Zep’s Key Features?

Temporal Knowledge Graph

This is Zep’s headline feature and the reason to pick it. Every fact in the graph is timestamped. When a user’s job title changes or a preference shifts, Zep tracks the new fact and marks the old one as no longer valid instead of leaving both floating around. Your agent can answer questions about what was true last month versus today. Simpler key-value memory stores cannot do this without you building the logic yourself.

Sub-200ms Retrieval at Scale

Zep claims sub-200ms retrieval times that stay flat as the graph grows to millions of context graphs. In practice that means memory lookups do not become the bottleneck in your agent’s response loop. The platform manages access controls and rate limits per project, with 600 requests per minute on Flex and 1,000 on Flex Plus.

Observations and Provenance

Flex Plus adds Observations, which surface behavioral patterns and recurrences across a user’s history rather than just raw facts. Every fact is traceable back to its source message or data record, so you can audit why your agent said what it said. For regulated teams, that provenance trail is not a nice-to-have, it is a requirement.

Framework-Agnostic SDKs

Zep ships Python, TypeScript, and Go SDKs and integrates in about three lines of code. You add messages and get context back in one call, and you can ingest structured business data into the same user graph. It works with any agent framework, so you are not locked into LangChain or any single stack. That flexibility matters because agent frameworks churn constantly, and you do not want your memory layer welded to whichever one is popular this quarter.

Custom Entities and Extraction Control

Out of the box Zep extracts entities and facts automatically, but you can also define custom entity and edge types to match your domain. The free plan allows 5 custom types, Flex allows 10, and Flex Plus allows 20. Flex Plus also unlocks custom extraction instructions, so you can steer what Zep pulls from a conversation. If your agent deals with a specialized vocabulary, medical terms, financial instruments, internal product names, this control keeps the graph clean and relevant instead of cluttered with noise.

How Much Does Zep Cost?

Zep starts free with 1,000 credits per month, then jumps to $125/month for the Flex plan and 50,000 credits. Flex Plus is $375/month for 200,000 credits and adds Observations, webhooks, and analytics. Enterprise is custom and brings SOC 2 Type II, a HIPAA BAA, and a dedicated account manager.

The credit model is where you need to do math. Overage on Flex runs $25 per 10,000 credits, and a high-traffic agent burns credits faster than you expect. Compare that to Mem0, which offers a free tier of 10,000 requests per month and a $19/month Starter plan, and Zep looks expensive on paper. The difference is what you get for the money: a temporal graph and enterprise governance versus a simpler memory store.

For a small team prototyping, the free tier is fine. For a production agent serving thousands of users, budget for Flex Plus or an Enterprise contract. This is not a tool where the entry price tells the whole story.

One thing the credit model does well is auto top-up. Flex and Flex Plus both refill credits automatically at a 20% threshold, so your agent does not suddenly go dark mid-month when it runs out. That predictability is worth something in production, even if it means your bill can creep. Just set a budget alert and watch your credit burn rate for the first few weeks, because real traffic almost always uses more than your test traffic suggested.

Who is Zep Best For?

Use Zep if you are shipping a production AI agent where memory accuracy over time actually matters. Customer support agents, health coaching apps, and sales assistants that track evolving user context are the sweet spot. The temporal graph and provenance trail pay off when wrong or stale facts cause real problems.

Use Zep if you need enterprise governance. SOC 2, HIPAA BAA support, audit logs, and access controls are built in, which saves you from bolting compliance onto a simpler tool later.

Skip Zep if you are building a weekend project or a chatbot that does not need to remember much. The free tier works for prototyping, but the graph model adds complexity you may not need. A flat key-value memory or a cheaper tool will get you there faster. Also skip it if you require a self-hosted open-source deployment, since that is not Zep’s model on paid plans.

Best Zep Alternatives

Mem0

Mem0 is the most popular general-purpose memory layer and the obvious budget alternative. It combines vector, graph, and key-value storage with automatic memory extraction, and it has the largest community in the space with tens of thousands of GitHub stars. The free tier covers 10,000 requests per month and the Starter plan is $19/month, far below Zep’s $125 Flex. Mem0 is the better pick for personalization and long-term user profiles. Zep wins when temporal relationships are the whole point.

Letta

Letta takes a different approach. Instead of a passive memory layer you query, Letta is a stateful agent runtime with memory built into the agent architecture. If you are building a new autonomous agent from scratch rather than adding memory to an existing app, Letta may fit better. Pricing runs roughly $0.00015 per second of tool execution on the API, with self-hosted deployments possible. It is more of a framework commitment than Zep’s drop-in SDK.

Cognee

Cognee is the open-source option for teams that want to self-host their memory graph. It builds a knowledge graph from your data and you run it on your own infrastructure, which means no per-credit billing and full data control. The tradeoff is you operate it yourself, with no managed sub-200ms guarantees or built-in SOC 2. Cognee suits teams with strict data residency needs or a tight budget who can handle the ops work.

Final Verdict: Is Zep Worth It?

Zep is worth it for teams that have outgrown simple memory and need an agent that understands time. The temporal knowledge graph is genuinely useful: timestamping every fact and invalidating stale data is the kind of thing you would otherwise build yourself and get wrong. Pair that with sub-200ms retrieval and enterprise governance, and Zep earns its 7.8 as a serious production tool.

The catch is cost. Credit pricing climbs quickly, and at $125/month to start, Zep is not the tool you reach for casually. If your agent needs time-aware memory and you can justify the spend, Zep is the strongest pick in the category. If you just need basic personalization, Mem0 will save you money and get the job done. Our take: try the free tier with realistic test data first, watch how fast you burn credits, and only commit once you have seen the temporal graph solve a problem your old approach could not. For the right team, it is one of the most capable memory layers shipping today.