--- summary: "Local-first search sidecar with BM25, vectors, reranking, and query expansion" title: "QMD memory engine" read_when: - You want to set up QMD as your memory backend - You want advanced memory features like reranking or extra indexed paths --- [QMD](https://github.com/tobi/qmd) is a local-first search sidecar that runs alongside OpenClaw. It combines BM25, vector search, and reranking in a single binary, and can index content beyond your workspace memory files. ## What it adds over builtin - **Reranking and query expansion** for better recall. - **Index extra directories** - project docs, team notes, anything on disk. - **Index session transcripts** - recall earlier conversations. - **Fully local** - runs with the official llama.cpp provider plugin and auto-downloads GGUF models. - **Automatic fallback** - if QMD is unavailable, OpenClaw falls back to the builtin engine seamlessly. ## Getting started ### Prerequisites - Install QMD: `npm install -g @tobilu/qmd` or `bun install -g @tobilu/qmd` - SQLite build that allows extensions (`brew install sqlite` on macOS). - QMD must be on the gateway's `PATH`. - macOS and Linux work out of the box. Windows is best supported via WSL2. ### Enable ```json5 { memory: { backend: "qmd", }, } ``` OpenClaw creates a self-contained QMD home under `~/.openclaw/agents//qmd/` and manages the sidecar lifecycle automatically - collections, updates, and embedding runs are handled for you. It prefers current QMD collection and MCP query shapes, but falls back to alternate collection-pattern flags and older MCP tool names when needed. Startup reconciliation also recreates stale managed collections back to their canonical patterns when an older QMD collection with the same name is still present. ## How the sidecar works - OpenClaw creates collections from your workspace memory files and any configured `memory.qmd.paths`, then runs `qmd update` when the QMD manager opens and periodically afterward (`memory.qmd.update.interval`, default `5m`). Refreshes run through QMD subprocesses, not an in-process filesystem crawl. Semantic search modes also run `qmd embed` (`memory.qmd.update.embedInterval`, default `60m`). - The default workspace collection tracks `MEMORY.md` plus the `memory/` tree. Lowercase `memory.md` is not indexed as a root memory file. - QMD's own scanner ignores hidden paths and common dependency/build directories such as `.git`, `.cache`, `node_modules`, `vendor`, `dist`, and `build`. Gateway startup does not initialize QMD by default (`memory.qmd.update.startup` defaults to `off`), so cold boot avoids importing the memory runtime or creating the long-lived watcher before memory is first used. - Set `memory.qmd.update.startup` to `idle` or `immediate` to initialize QMD at gateway start anyway. `memory.qmd.update.onBoot` defaults to `true` and runs the initial refresh at startup; set it to `false` to skip that immediate refresh (the long-lived manager still opens when update or embed intervals are configured, so QMD keeps owning its regular watcher/timers). - Searches use the configured `searchMode` (default: `search`; also supports `vsearch` and `query`). `search` is BM25-only, so OpenClaw skips semantic vector readiness probes and embedding maintenance in that mode. If a mode fails, OpenClaw retries with `qmd query`. - When `searchMode` is `query`, set `memory.qmd.rerank` to `false` to use QMD's hybrid query path without the reranker (requires QMD 2.1 or newer). OpenClaw passes `--no-rerank` to the direct QMD CLI path and `rerank: false` to QMD's MCP query tool. - With QMD releases that advertise multi-collection filters, OpenClaw groups same-source collections into one QMD search invocation. Older QMD releases keep the compatible per-collection fallback. - If QMD fails entirely, OpenClaw falls back to the builtin SQLite engine. Repeated chat-turn attempts back off briefly after an open failure so a missing binary or broken sidecar dependency does not create a retry storm; `openclaw memory status` and one-shot CLI probes still recheck QMD directly. The first search may be slow - QMD auto-downloads GGUF models (~2 GB) for reranking and query expansion on the first `qmd query` run. ## Search performance and compatibility OpenClaw keeps the QMD search path compatible with both current and older QMD installs. On startup, OpenClaw checks the installed QMD help text once per manager. If the binary advertises support for multiple collection filters, OpenClaw searches all same-source collections with one command: ```bash qmd search "router notes" --json -n 10 -c memory-root-main -c memory-dir-main ``` This avoids starting one QMD subprocess per durable-memory collection. Session transcript collections stay in their own source group, so mixed `memory` + `sessions` searches still give the result diversifier input from both sources. Older QMD builds only accept one collection filter. When OpenClaw detects one of those builds, it keeps the compatibility path and searches each collection separately before merging and deduplicating results. To inspect the installed contract manually, run: ```bash qmd --help | grep -i collection ``` Current QMD help mentions targeting one or more collections. Older help usually describes a single collection. ## Model overrides QMD model environment variables pass through unchanged from the gateway process, so you can tune QMD globally without adding new OpenClaw config: ```bash export QMD_EMBED_MODEL="hf:Qwen/Qwen3-Embedding-0.6B-GGUF/Qwen3-Embedding-0.6B-Q8_0.gguf" export QMD_RERANK_MODEL="/absolute/path/to/reranker.gguf" export QMD_GENERATE_MODEL="/absolute/path/to/generator.gguf" ``` After changing the embedding model, rerun embeddings so the index matches the new vector space. ## Indexing extra paths Point QMD at additional directories to make them searchable: ```json5 { memory: { backend: "qmd", qmd: { paths: [{ name: "docs", path: "~/notes", pattern: "**/*.md" }], }, }, } ``` Snippets from extra paths appear as `qmd//` in search results. `memory_get` understands this prefix and reads from the correct collection root. ## Indexing session transcripts Enable session indexing to recall earlier conversations. QMD needs both the general `memorySearch` session source and the QMD transcript exporter: ```json5 { agents: { defaults: { memorySearch: { experimental: { sessionMemory: true }, sources: ["memory", "sessions"], }, }, }, memory: { backend: "qmd", qmd: { sessions: { enabled: true }, }, }, } ``` Transcripts export as sanitized User/Assistant turns into a dedicated QMD collection under `~/.openclaw/agents//qmd/sessions/`. Setting only `memorySearch.experimental.sessionMemory` does not export transcripts into QMD. Session hits are still filtered by [`tools.sessions.visibility`](/gateway/config-tools#toolssessions). The default `tree` visibility does not expose unrelated same-agent sessions. If a gateway-dispatched session should be recallable from a separate DM session, set `tools.sessions.visibility: "agent"` intentionally. ## Search scope By default, QMD search results are surfaced only in direct sessions (not group or channel chats). Configure `memory.qmd.scope` to change this: ```json5 { memory: { qmd: { scope: { default: "deny", rules: [{ action: "allow", match: { chatType: "direct" } }], }, }, }, } ``` The snippet above is the actual default rule. When scope denies a search, OpenClaw logs a warning with the derived channel and chat type so empty results are easier to debug. ## Citations When `memory.citations` is `auto` or `on`, search snippets get a `Source: #L` (or `#L-L`) footer appended. In `auto` mode the footer is added only for direct-chat sessions. Set `memory.citations = "off"` to omit the footer while still passing the path to the agent internally. ## When to use Choose QMD when you need: - Reranking for higher-quality results. - To search project docs or notes outside the workspace. - To recall past session conversations. - Fully local search with no API keys. For simpler setups, the [builtin engine](/concepts/memory-builtin) works well with no extra dependencies. ## Troubleshooting **QMD not found?** Ensure the binary is on the gateway's `PATH`. If OpenClaw runs as a service, create a symlink: `sudo ln -s ~/.bun/bin/qmd /usr/local/bin/qmd`. If `qmd --version` works in your shell but OpenClaw still reports `spawn qmd ENOENT`, the gateway process likely has a different `PATH` than your interactive shell. Pin the binary explicitly: ```json5 { memory: { backend: "qmd", qmd: { command: "/absolute/path/to/qmd", }, }, } ``` Use `command -v qmd` in the environment where QMD is installed, then recheck with `openclaw memory status --deep`. **First search very slow?** QMD downloads GGUF models on first use. Pre-warm with `qmd query "test"` using the same XDG dirs OpenClaw uses. **Many QMD subprocesses during search?** Update QMD if possible. OpenClaw uses one process for same-source multi-collection searches only when the installed QMD advertises support for multiple `-c` filters; otherwise it keeps the older per-collection fallback for correctness. **BM25-only QMD still trying to build llama.cpp?** Set `memory.qmd.searchMode = "search"`. OpenClaw treats that mode as lexical-only, skips QMD vector status probes and embedding maintenance, and leaves semantic readiness checks to `vsearch` or `query` setups. **Search times out?** Increase `memory.qmd.limits.timeoutMs` (default: 4000ms). Set it higher, for example `120000`, for slower hardware. **Empty results in group or channel chats?** This is expected with the default `memory.qmd.scope`, which allows only direct sessions. Add an `allow` rule for `group` or `channel` chat types if you want QMD results there. **Root memory search suddenly got too broad?** Restart the gateway or wait for the next startup reconciliation. OpenClaw recreates stale managed collections back to canonical `MEMORY.md` and `memory/` patterns when it detects a same-name conflict. **Workspace-visible temp repos causing `ENAMETOOLONG` or broken indexing?** QMD traversal follows the underlying QMD scanner rather than OpenClaw's builtin symlink rules. Keep temporary monorepo checkouts under hidden directories like `.tmp/` or outside indexed QMD roots until QMD exposes cycle-safe traversal or explicit exclusion controls. ## Configuration For the full config surface (`memory.qmd.*`), search modes, update intervals, scope rules, and all other knobs, see the [Memory configuration reference](/reference/memory-config). ## Related - [Memory overview](/concepts/memory) - [Builtin memory engine](/concepts/memory-builtin) - [Honcho memory](/concepts/memory-honcho)