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+# Mem0 OSS Memory Plugin
+
+Self-hosted, privacy-first long-term memory using the open-source
+[mem0ai](https://github.com/mem0ai/mem0) library.  No cloud API key or
+external service needed — everything runs on your machine.
+
+## How it works
+
+- **LLM fact extraction** — after each conversation turn, mem0 uses an LLM
+  to extract important facts, preferences, and context from the exchange.
+- **Semantic search** — memories are stored in a local [Qdrant](https://qdrant.tech/)
+  vector database.  Searches use embedding-based similarity so natural-language
+  queries work well.
+- **Automatic deduplication** — mem0 merges new facts with existing ones to
+  avoid duplicate storage.
+- **Built-in memory mirroring** — writes via the built-in `memory` tool are
+  automatically mirrored into mem0 via `on_memory_write`, so nothing is lost
+  whether you use the native tool or the mem0-specific tools.
+
+## Setup
+
+### 1. Install dependencies
+
+```bash
+pip install mem0ai qdrant-client
+```
+
+### 2. Configure a backend
+
+**Zero extra config — auto-detect (recommended)**
+
+If you already have a Hermes provider configured (OpenRouter, Anthropic, OpenAI,
+or AWS Bedrock), mem0 OSS will automatically pick it up — no `MEM0_OSS_*` vars
+needed.  The plugin mirrors the standard Hermes auxiliary provider priority:
+
+```
+OPENROUTER_API_KEY  →  uses OpenRouter (openrouter → openai adapter)
+ANTHROPIC_API_KEY   →  uses Anthropic directly
+OPENAI_API_KEY      →  uses OpenAI (+ OPENAI_BASE_URL if set)
+AWS_ACCESS_KEY_ID   →  uses AWS Bedrock (boto3 reads creds automatically)
+```
+
+The first matching key wins.
+
+**Option A — config.yaml (preferred for per-provider control)**
+
+The plugin inherits from `auxiliary.default` if no `auxiliary.mem0_oss` block
+exists, so if you've already set a default auxiliary provider for other tasks
+you get mem0 OSS for free:
+
+```yaml
+# ~/.hermes/config.yaml
+auxiliary:
+  default:                    # inherited by mem0_oss and all other aux tasks
+    provider: auto
+    model: us.anthropic.claude-haiku-4-5-20251001-v1:0
+
+  # Optional — override just for mem0_oss:
+  mem0_oss:
+    provider: openrouter      # or openai, anthropic, ollama, aws_bedrock, custom
+    model: openai/gpt-4o-mini
+    # api_key: ...            # optional — falls back to provider's standard env var
+    # base_url: ...           # optional — for custom/local endpoints
+```
+
+Supported provider values: `openrouter`, `openai`, `anthropic`, `ollama`,
+`lmstudio`, `aws_bedrock` (alias: `bedrock`), `custom`, `auto`.
+`auto` uses the same env-var detection order as zero-config.
+
+**Option B — AWS Bedrock**
+
+If you already use Hermes with Bedrock, no additional config is needed.
+The plugin reuses `AWS_ACCESS_KEY_ID` / `AWS_SECRET_ACCESS_KEY` / `AWS_REGION`.
+
+LLM default: `us.anthropic.claude-haiku-4-5-20251001-v1:0`
+Embedder default: `amazon.titan-embed-text-v2:0` (1024-dim)
+
+**Option C — OpenAI**
+
+```bash
+# If OPENAI_API_KEY is already set, nothing more is needed.
+# Override model/embedder explicitly if desired:
+export MEM0_OSS_LLM_MODEL=gpt-4o-mini
+export MEM0_OSS_EMBEDDER_MODEL=text-embedding-3-small
+export MEM0_OSS_EMBEDDER_DIMS=1536
+```
+
+**Option D — Ollama (fully local, no API key)**
+
+```bash
+export MEM0_OSS_LLM_PROVIDER=ollama
+export MEM0_OSS_LLM_MODEL=llama3.2
+export MEM0_OSS_EMBEDDER_PROVIDER=ollama
+export MEM0_OSS_EMBEDDER_MODEL=nomic-embed-text
+export MEM0_OSS_EMBEDDER_DIMS=768
+```
+
+### 3. Activate
+
+```yaml
+# ~/.hermes/config.yaml
+memory:
+  provider: mem0_oss
+```
+
+Or use the interactive setup wizard:
+
+```bash
+hermes memory setup    # select "mem0_oss"
+```
+
+## Storage
+
+| Path | Contents |
+|------|----------|
+| `$HERMES_HOME/mem0_oss/qdrant/` | Qdrant vector store (all memories) |
+| `$HERMES_HOME/mem0_oss/history.db` | mem0 history SQLite database |
+
+Override with `MEM0_OSS_VECTOR_STORE_PATH` and `MEM0_OSS_HISTORY_DB_PATH`.
+
+Non-secret settings can also be persisted to `$HERMES_HOME/mem0_oss.json`
+by the setup wizard (via `save_config`), or written manually — see
+[All configuration options](#all-configuration-options).
+
+## Agent tools
+
+| Tool | Description |
+|------|-------------|
+| `mem0_oss_search` | Semantic search over stored memories |
+
+Facts are extracted and stored automatically on every conversation turn via
+`sync_turn` — no explicit save call needed.
+
+Writes via the built-in `memory` tool are also mirrored automatically into
+mem0 via `on_memory_write`.  To explicitly save something mid-session, use
+the built-in `memory` tool; it will propagate to mem0 automatically.
+
+## Concurrent access (WebUI + gateway)
+
+The plugin uses embedded Qdrant which normally allows only one process at a
+time.  To avoid conflicts when both the WebUI and the gateway run on the same
+host, the plugin creates a fresh `Memory` instance per operation and releases
+the Qdrant lock immediately after each call.  If a brief overlap occurs the
+operation is skipped gracefully (logged at DEBUG, not counted as a failure)
+rather than raising an error.
+
+## All configuration options
+
+### Environment variables
+
+| Env var | Default | Description |
+|---------|---------|-------------|
+| `MEM0_OSS_LLM_PROVIDER` | auto-detected | LLM provider (`openrouter`, `openai`, `anthropic`, `ollama`, `aws_bedrock`, …) |
+| `MEM0_OSS_LLM_MODEL` | provider default | LLM model id |
+| `MEM0_OSS_EMBEDDER_PROVIDER` | mirrors LLM provider | Embedder provider |
+| `MEM0_OSS_EMBEDDER_MODEL` | provider default | Embedder model id |
+| `MEM0_OSS_EMBEDDER_DIMS` | provider default | Embedding dimensions |
+| `MEM0_OSS_COLLECTION` | `hermes` | Qdrant collection name |
+| `MEM0_OSS_USER_ID` | `hermes-user` | Memory namespace |
+| `MEM0_OSS_TOP_K` | `10` | Default search result count |
+| `MEM0_OSS_VECTOR_STORE_PATH` | `$HERMES_HOME/mem0_oss/qdrant` | On-disk Qdrant path |
+| `MEM0_OSS_HISTORY_DB_PATH` | `$HERMES_HOME/mem0_oss/history.db` | SQLite history path |
+| `MEM0_OSS_API_KEY` | _(auto-detected from provider env var)_ | Explicit API key for the LLM backend |
+| `MEM0_OSS_OPENAI_BASE_URL` | _(none)_ | OpenAI-compatible endpoint override |
+
+### config.yaml (auxiliary.mem0_oss / auxiliary.default)
+
+`auxiliary.mem0_oss` keys take precedence; any key not set there falls back to
+`auxiliary.default` (which is also used by compression, vision, and other aux tasks).
+
+| Key | Description |
+|-----|-------------|
+| `provider` | Hermes provider name (see auto-detect order above) |
+| `model` | LLM model id |
+| `base_url` | Custom OpenAI-compatible endpoint |
+| `api_key` | Explicit API key (takes precedence over env vars) |
+
+### Key resolution priority
+
+1. `MEM0_OSS_API_KEY` env var
+2. `auxiliary.mem0_oss.api_key` in `config.yaml`
+3. Provider's standard env var (`OPENROUTER_API_KEY`, `ANTHROPIC_API_KEY`,
+   `OPENAI_API_KEY`, …) resolved via the Hermes provider registry
+4. AWS credentials from environment (for Bedrock)
+
+Or put non-secret settings in `$HERMES_HOME/mem0_oss.json` (keys are the
+env-var names without the `MEM0_OSS_` prefix, in snake_case):
+
+```json
+{
+  "llm_provider": "aws_bedrock",
+  "llm_model": "us.anthropic.claude-haiku-4-5-20251001-v1:0",
+  "embedder_provider": "aws_bedrock",
+  "embedder_model": "amazon.titan-embed-text-v2:0",
+  "embedder_dims": 1024,
+  "collection": "hermes",
+  "user_id": "hermes-user",
+  "top_k": 10
+}
+```