---
type: Software
resource: https://hermes-agent.nousresearch.com/docs/user-guide/features/memory-providers
generated: { by: reference_agent/gemini-3.7-flash, at: 2026-08-23T15:58:45Z }
tags:
  - ai
  - memory
  - agents
  - opensource
sources:
  - resource: https://hermes-agent.nousresearch.com/docs/user-guide/features/memory-providers
    title: "Hermes Agent Memory Providers Documentation"
  - resource: https://github.com/NousResearch/Hermes-Agent
    title: "Hermes Agent GitHub Repository"
---

# Hermes Agent Memory Providers

Hermes Agent Memory Providers is a pluggable memory subsystem within Nous Research's autonomous Hermes Agent framework. While Hermes Agent includes a built-in file-based memory foundation (utilizing local `MEMORY.md` and `USER.md` markdown files), the memory provider interface enables users to attach specialized external memory engines for structured context capture, multi-hop recall, and cross-session knowledge synchronization.

```mermaid
graph TD
    Agent[Hermes Agent Core] <--> LocalBase["Default Local Foundation (MEMORY.md / USER.md)"]
    Agent <--> ProviderManager[Memory Provider Manager]

    subgraph "External Pluggable Memory Providers"
        ProviderManager <--> Honcho["Honcho (User modeling & plasticity)"]
        ProviderManager <--> Mem0["Mem0 (Cloud / local fact extraction)"]
        ProviderManager <--> OpenViking["OpenViking (Tiered L0/L1/L2 retrieval)"]
        ProviderManager <--> Holographic["Holographic (Local SQLite HRR algebra)"]
        ProviderManager <--> RetainDB["RetainDB (Hybrid BM25 + Vector)"]
        ProviderManager <--> ByteRover["ByteRover (Hierarchical markdown tree)"]
        ProviderManager <--> Hindsight["Hindsight (Knowledge graph reflection)"]
        ProviderManager <--> Supermemory["Supermemory (MCP context engine)"]
    end
```

## How Hermes Memory Providers Work

External memory providers in Hermes Agent operate alongside (rather than replacing) the built-in foundation:
1. **Pre-Turn Context Injection**: Before each agent turn, the active provider prefetches relevant memories based on the user's latest message and injects them into the system prompt context.
2. **Post-Turn Synchronization**: After the agent responds or executes tools, the provider synchronizes conversation turns and extracts new facts asynchronously.
3. **Agent Memory Tools**: Provides the agent with specialized tools to search, update, or clear stored memories.

---

## Supported Providers Breakdown

| Provider | Storage Architecture | Local / Open Source | Unique Strengths |
| :--- | :--- | :--- | :--- |
| **[Honcho](honcho.md)** | Relational / Dynamic User Graph | Yes (Local Docker / SaaS) | AI-native user modeling, dialectic reasoning, and theory-of-mind plasticity. |
| **[Mem0](mem0.md)** | Vector + Structured Fact Layer | Yes (Local / Cloud) | Automated fact extraction, deduplication, and user/agent/session scoping. |
| **OpenViking** | Tiered Context Storage | Yes (Self-hosted) | Multi-tier L0/L1/L2 loading designed to reduce context token usage by 80–90%. |
| **Holographic** | Local SQLite Embedded DB | Yes (Local embedded) | Uses Holographic Reduced Representations (HRR) vector-symbolic algebra with zero cloud dependencies. |
| **RetainDB** | Hybrid Database Index | Cloud / Self-hosted | Multi-modal hybrid search combining dense vectors, BM25 keyword matching, and rerankers. |
| **ByteRover** | Markdown Knowledge Tree | Yes (Local / Cloud) | Hierarchical knowledge tree stored in human-readable Markdown with tiered retrieval pipelines. |
| **Hindsight** | Reflective Knowledge Graph | Local / Cloud | Extracts discrete entity facts and performs multi-hop reflective reasoning over conversational history. |
| **[Supermemory](supermemory.md)** | Knowledge Graph + MCP Connectors | Yes (Local / Cloud) | Universal context engine connecting bookmarks, documents, and external apps. |

---

## Configuration & Usage

Hermes Agent allows selecting and switching memory providers via CLI or YAML configuration:

### Interactive Setup
```bash
hermes memory setup
```

### Check Memory Status
```bash
hermes memory status
```

### Manual Configuration (`~/.hermes/config.yaml`)
```yaml
memory:
  provider: "honcho" # Options: honcho, mem0, openviking, holographic, retaindb, byterover, hindsight, supermemory
  sync_enabled: true
  prefetch_limit: 5
```

## Related Concepts

- [LLM and Agent Memory](memory.md) - Foundational agent memory concepts and cognitive taxonomy.
- [Honcho](honcho.md) - Dynamic user modeling and plasticity engine.
- [Mem0](mem0.md) - Vector-first memory layer.
- [Supermemory](supermemory.md) - Context engine and second brain.
- [Claude-Mem (cmem.ai)](cmem.md) - Persistent memory stream for coding agents.