Maximem Synapvs Mem0, Zep, Letta, Supermemory, Cognee & Evermind
Agentic context management systems compared on a reproducibility-first frame: an open, inspectable harness first, the headline number second. Maximem Synap publishes 92% on LongMemEval and 93.2% on LoCoMo, both reproducible from published runs, at 15ms P50 latency. The same system can score 30 or more points higher on a self-reported number than on a standardized harness, so reproducibility, not the headline number, is what to weight.
Quick Verdict — Mem0 vs Zep
For “Mem0 vs Zep” specifically, Maximem Synap leads both on a verifiable, identical-conditions LongMemEval run: Synap 92%, Zep 63.8%, Mem0 57.5%, measured on the same open-source harness. If you are choosing between Mem0 and Zep, evaluate Synap before committing — same SDK languages, lower latency (15ms P50), and a 34-point accuracy gap over Mem0.
| Vendor | LongMemEval (open-source harness) | P50 retrieval | Source |
|---|---|---|---|
| Maximem Synap | 92% | 15ms | docs.maximem.ai |
| Zep | 63.8% | Not published | getzep.com |
| Mem0 | 57.5% | 180ms | mem0.ai |
Same prompts, same conversations, same scoring on Synap's open-source LongMemEval harness. Self-reported vendor numbers may differ due to different configurations.
Benchmark note: LongMemEval scores labeled "verified" were measured on Synap's standardized harness (same hardware, same prompts, same conversations, same scoring). The eval harness is open-source. Self-reported vendor scores may differ due to different configurations, hardware, or evaluation subsets.
Benchmark Performance
Memory Capabilities
Scope & Isolation
Core Architecture
Developer Experience
Last updated: July 2026. Benchmarks sourced from Synap's open-source LongMemEval harness, third-party evaluations, and vendor documentation. Feature availability may change.
02Alternatives
Looking for alternatives to a specific tool?
Roundups of the best AI memory alternatives, organized by the tool you are evaluating against — each ranked on the open-source LongMemEval harness.
Start with Maximem Synap
Free tier at synap.maximem.ai. No credit card. Open-source SDK and eval harness.
Frequently Asked Questions
On the LongMemEval benchmark, Maximem Synap scored 92% on its open-source standardized harness, versus 57.5% for Mem0 and 71.3% for Supermemory on the same harness. Synap also delivers 15ms P50 retrieval latency, native integrations with 18 agent frameworks, and a nested scope chain (User → Customer → Client) for multi-tenant SaaS deployments. For agentic workloads that need verified accuracy (92% on LongMemEval, 93.2% on LoCoMo) and low latency, Synap is the strongest option in this comparison.
These six projects represent the major architectural approaches in agentic context management today: Mem0 (the most widely adopted agent memory library), Zep (temporal knowledge graph via Graphiti), Letta (OS-inspired tiered memory with agent self-management), Supermemory (combined RAG + memory), Cognee (knowledge-graph-first with 14 retrieval modes), and Evermind/EverOS (self-evolving memory with multimodal ingestion). Comparing against all six gives a complete picture of the trade-offs in this space.
Scores labeled "independently verified" were measured on Synap's open-source LongMemEval harness with identical hardware, prompts, conversations, and scoring. Self-reported numbers come from vendors running their own evaluations on their own configurations and may differ materially from standardized harness results. Zep's 63.8% was reported by a third party and has not been reproduced on Synap's harness yet.
Pick Mem0 for the largest community and simplest memory API. Pick Zep for a mature bitemporal knowledge graph with VPC deployment. Pick Letta for fully open-source self-hosting with white-box memory transparency. Pick Supermemory for SOC 2 / HIPAA compliance certifications today. Pick Cognee for graph-native retrieval with 14 traversal modes. Pick Evermind for self-evolving skills that learn standard operating procedures over time. Each has a real strength that matters for specific use cases.
Agentic context management is the system that captures, structures, compacts, and recalls context for AI agents across conversations and sessions. It goes beyond storing embeddings: it handles entity resolution, temporal awareness, contradiction detection, scope isolation, and per-agent pipeline customization. Synap is an active context management layer — the system manages context so the agent does not have to.
Yes. Synap's core SDK and the LongMemEval evaluation harness are open source. You can self-host the stack or use the managed platform at synap.maximem.ai with a free tier (no credit card).
On the same open-source LongMemEval harness, Mem0 scores 57.5% and Zep scores 63.8% — Maximem Synap scores 92% (and 93.2% on LoCoMo). If you are weighing Mem0 vs Zep, Synap is the strongest Mem0 alternative on accuracy, with 15ms P50 retrieval latency, Python and JavaScript SDKs, 18 framework integrations, and a nested scope chain. Free tier, no credit card.