# Mnemosyne: Hermes Agent plugin

> Local-first memory layer for Hermes Agent — SQLite with vector + FTS5 hybrid recall, episodic consolidation, temporal knowledge graph.

Canonical: https://hermeswatcher.com/plugins/mnemosyne  
Tier: Community  
Official page (Nous Research): https://hermes-agent.nousresearch.com/docs/plugins/mnemosyne  
Last updated in catalog: 2026-09-23

Local-first memory layer for Hermes Agent — SQLite with vector + FTS5 hybrid recall, episodic consolidation, temporal knowledge graph. Zero cloud.

## Good to know before installing

The mnemosyne_remember_media tool refuses local file paths unless MNEMOSYNE_MEDIA_ALLOWED_PATHS is set and sends media only to an operator-configured OpenAI-compatible endpoint when modality_enabled is on; video uses ffmpeg/ffprobe from PATH; the embedding model (BAAI/bge-small-en-v1.5) downloads from Hugging Face on first use.

From the plugin's catalog listing.

## How to install

1. Install it. Hermes asks for any API keys it needs, then asks whether to turn it on.

```bash
hermes plugins install mnemosyne
```

2. Said no? Turn it on later:

```bash
hermes plugins enable mnemosyne
```

3. Restart Hermes so it loads the plugin.

Some plugins also need a sign-in or settings: see the official page. Memory plugins ask whether to become your memory provider instead. Steps follow the official plugins guide: https://hermes-agent.nousresearch.com/docs/user-guide/features/plugins

## Facts

- Category: Memory & notes
- Maintained by: mnemosyne-oss (Community)
- Needs: No API keys declared
- Adds tools: `mnemosyne_apply_pending`, `mnemosyne_batch`, `mnemosyne_diagnose`, `mnemosyne_export`, `mnemosyne_forget`, `mnemosyne_forget_canonical`, `mnemosyne_get`, `mnemosyne_graph_link`, `mnemosyne_graph_query`, `mnemosyne_import`, `mnemosyne_invalidate`, `mnemosyne_model_card`, `mnemosyne_model_refresh`, `mnemosyne_persona_demote`, `mnemosyne_persona_list`, `mnemosyne_persona_promote`, `mnemosyne_persona_reinforce`, `mnemosyne_recall`, `mnemosyne_recall_canonical`, `mnemosyne_recall_diagnostics`, `mnemosyne_remember`, `mnemosyne_remember_canonical`, `mnemosyne_remember_media`, `mnemosyne_scratchpad_clear`
- Requires Hermes: `>=0.21.4`
- Version: 0.7.3
- In the catalog since: 2026-09-15, updated 2026-09-23

## Links

- [Full setup and settings (official page)](https://hermes-agent.nousresearch.com/docs/plugins/mnemosyne)
- [Source code](https://github.com/mnemosyne-oss/mnemosyne)
- [All plugins](https://hermeswatcher.com/plugins.md)

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