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Sessions and memory

Memory search

memory_search finds relevant notes from your memory files, even when the wording differs from the original text. It chunks memory into small pieces and searches them with embeddings, keywords, or both.

The built-in index supports SQLite and qualified PostgreSQL runtimes. Search uses engine-local text ranking, so scores and ordering can differ from SQLite. It requires unaccent for text search, pg_trgm for the trigram tokenizer, and vector for semantic search. Explicit memory.search.provider: "none" enables keyword-only search without vector; memory status reports this as fts-only. See PostgreSQL memory search for lifecycle behavior and Database engines for extension setup.

On PostgreSQL, both body keywords and filename/path lookup use the admitted index. Source and selected-agent scope restrict candidates before the result limit; semantic retrieval also filters the embedding model. Text uses native full-text ranking; semantic retrieval preselects candidates with binary sketches, then reranks them by exact cosine distance over a derived float32 vector projection. Small candidate-ID scopes use exact search. Hybrid search keeps the same vector/text weights, but PostgreSQL text scores are not SQLite BM25 scores. A phrase with nearby terms can rank above scattered terms without promising identical ordering across engines.

PostgreSQL memory queries accept at most 4,096 UTF-16 code units and 128 terms, return at most 200 hits, and bound each snippet to 700 characters. Larger queries return an actionable error before search. Memory transcript recall retains its existing 200-candidate window followed by session visibility checks; it does not promise complete recall beyond that window or SQL-level session permission filtering.

The result-count argument is maxResults (an integer of at least 1). The tool also accepts max_results and limit as aliases. If several are supplied, maxResults takes precedence over max_results, which takes precedence over limit, regardless of argument order. Only the selected value is validated; an invalid higher-priority value is rejected rather than falling back to a valid alias. The advertised tool schema continues to use maxResults.

When indexing Markdown, the builtin engine attaches a heading-only chunk to the following content chunk. This keeps short headings from taking search result slots on their own while preserving section context and source line references. A final heading with no following content stays searchable. Oversized headings already split across chunks keep their fragments, and provider input limits still apply to merged chunks. Headings with their own recall annotations remain independent, preserving their project scope, triggers, and importance. Heading-like fragments inside a curated entry stay with that entry's annotation scope.

After upgrading, existing builtin indexes rebuild once on the next normal search or sync to apply this chunking change. No configuration change or manual memory index --force is needed. Memory files and database schemas are unchanged; keyword search remains available if the rebuild cannot finish immediately.

Quick start

OpenClaw uses OpenAI embeddings by default. To use another provider, set it explicitly:

json5
{  memory: {    search: {      provider: "openai", // or "gemini", "voyage", "mistral", "bedrock", "local", "ollama", "omlx", "lmstudio", "github-copilot", "openai-compatible"    },  },}

provider can also reference a custom models.providers.<id> entry (for example ollama-5080), as long as that entry sets api to "ollama" or another provider id with a memory embedding adapter. Entries using api: "openai-completions", api: "openai-responses", or a baseUrl without an explicit API use the generic OpenAI-compatible bridge. For ClawRouter, see Text embeddings for memory for the /v1 base URL, explicit router credential binding, and qualified model id.

For local embeddings with no API key, install and configure the official llama.cpp provider, then set provider: "local":

bash
openclaw plugins install @openclaw/llama-cpp-provider

Choose llama.cpp once in interactive setup. OpenClaw installs a verified llama-server, downloads the embedding GGUF, and writes its managed service configuration.

Managed local, Ollama, and OpenAI-compatible endpoints on loopback addresses (localhost, 127.0.0.0/8, ::1) index one file at a time when batch indexing is disabled. This limits the backlog that interactive searches share with background indexing. Other endpoints default to four indexing jobs. Serial indexing can make large rebuilds slower on servers with spare parallel capacity.

EmbeddingGemma uses its trained task prefixes automatically for queries and indexed documents, including through Ollama, LM Studio, and OpenAI-compatible providers. After upgrading, an existing unprefixed EmbeddingGemma index rebuilds once on the next search or sync. OpenClaw generates fresh embeddings rather than reusing unprefixed cache entries. Keyword search remains available if the rebuild cannot finish immediately; no manual memory index --force is needed. Remove any proxy workaround that adds these prefixes so they are not applied twice.

Some OpenAI-compatible embedding endpoints require asymmetric input_type labels, such as "query" for searches and "document"/"passage" for indexed chunks. Set these with queryInputType and documentInputType; see Memory configuration reference.

Supported providers

Provider ID Needs API key Notes
Bedrock bedrock No Uses the AWS credential chain
DeepInfra deepinfra Yes Default model BAAI/bge-m3
Gemini gemini Yes Supports image/audio indexing
GitHub Copilot github-copilot No Uses your Copilot subscription
Local local No Managed llama.cpp GGUF, ~0.3 GB
LM Studio lmstudio No Local/self-hosted server
Mistral mistral Yes Default model mistral-embed
Ollama ollama No Local/self-hosted server
oMLX omlx No Apple Silicon; explicit embedding model
OpenAI openai Depends API key or eligible Codex OAuth
OpenAI-compatible openai-compatible Usually Generic /v1/embeddings endpoint
Voyage voyage Yes Default model voyage-4-large

To move off Ollama, llmman serves the same /api/embed, so provider: "ollama" only needs a new remote.baseUrl.

For models that require a query prefix, set memory.search.queryInstruction, for example "search_query: " for a Nomic model served under a generic alias. It changes query text only and does not require rebuilding the document index.

How search works

OpenClaw runs two retrieval paths in parallel and merges the results:

flowchart LR
    Q["Query"] --> E["Embedding"]
    Q --> T["Tokenize"]
    E --> VS["Vector search"]
    T --> BM["Text search"]
    VS --> M["Weighted merge"]
    BM --> M
    M --> D["Recency and importance"]
    D --> R["MMR diversity"]
    R --> O["Top results"]
  • Vector search matches similar meaning ("gateway host" matches "the machine running OpenClaw").
  • Keyword search matches exact terms (IDs, error strings, config keys). It accepts NFC and NFD Unicode spellings without rewriting notes or rebuilding existing indexes, including notes that mix those forms across words. Search first requires every query term. Only when neither body nor filename search finds a match does it retry body search once with any query term and language-specific keyword expansion. SQLite ranks by BM25; PostgreSQL uses its native full-text rank or trigram similarity. This recovers answers without broadening a keyword query that already has matches.
  • Filename search indexes paths separately from note bodies. Exact full paths, basenames, and filename stems rank ahead of partial path matches, while snippets and body keyword scores still come from note content.

If only one path is available, the other runs alone. Keyword boosts stay bounded without clipping distinct lexical scores to the same maximum, so relevance continues to influence ranking when dated notes decay.

When both paths return results, the builtin engine scales each query's keyword scores before weighting them. The strongest keyword match earns at most the best semantic score, and every other keyword match earns a share in proportion to its BM25 relevance, never more than its own keyword score. A match much weaker than the query's best keyword match adds little, so sharing a common word rarely outweighs a note that is closer in meaning. This matters most for questions asked in a different language than the notes. minScore applies to the weighted sum of the cosine similarity and the scaled keyword score.

The builtin engine then applies fixed ranking rules:

text
hybrid relevance × recency decay × importance multiplier

Importance is scored once when an entry is written by a memory workflow that already has a model in the loop. Missing importance is neutral, so existing indexes keep their previous relevance signal. Dated daily notes decay with a 30-day half-life; curated files such as MEMORY.md and USER.md are evergreen. This follows the relevance, recency, and importance result in Generative Agents (arXiv:2304.03442) without adding a query-time model call.

MMR then reorders the scored hybrid candidate set to reduce redundant snippets. It does not change scores, threshold eligibility, or make another provider call.

The minScore threshold uses relevance before recency decay, including importance and project weighting. Recency changes the ordering of eligible hits, not whether they qualify. A relevant dated note can therefore return with a final score below minScore. Result limits still apply: an eligible older note can rank outside the returned window.

Search preserves keyword matches when every result's pre-decay score falls below the configured minimum score. Hybrid search can also fill remaining result slots with keyword-only matches. These rules also apply in project sessions; semantic-only matches still need to meet the configured minimum score.

Hybrid ranking also scores retrieved keyword candidates from their stored embeddings when they fall outside the top vector candidates. This keeps a strong keyword answer eligible when many similar notes fill the vector window.

Rule-based trigger recall

On eligible interactive turns, the builtin engine also compares the inbound message with short trigger phrases stored on indexed entries. Strong matches can add up to three compact entries to hidden context before the reply. The prefilter uses the existing keyword and vector retrieval paths and does not run a recall model.

Automatic injection is deliberately narrower than memory_search: only promoted, trusted entries qualify. Until indexed provenance is available, that means entries from root MEMORY.md and USER.md only. Daily notes, imported transcripts, and session transcripts remain available through explicit memory tools or Active Memory escalation, but are never injected automatically.

FTS-only mode. Set provider: "none" to intentionally disable embeddings and search with keywords only. Leaving provider unset or set to "auto" falls back to keyword-only ranking when embedding setup or a request fails, as does provider: "local" (the GGUF/llama.cpp provider). Creation-time fallback still indexes text for keyword search, including manual and background indexing before the first search. memory_search includes the redacted embedding-bootstrap reason in debug.embeddingBootstrap even when there are no matches.

A failed local embedding request preserves keyword access to a matching index and records the degraded provider in memory status and Gateway logs. A query embedding that comes back as all zeros skips vector recall for that search and is reported in the Gateway log, so keyword-only results never pass silently. A real model or index-configuration mismatch still pauses search instead of serving mismatched data.

Explicit provider unavailable. If you name any other provider explicitly (for example openai, ollama, gemini) and it becomes unavailable at request time (bad auth, network failure), memory_search reports memory as unavailable instead of silently degrading to FTS-only results. This keeps a broken configured provider visible. Set provider: "none" for deliberate FTS-only recall, or fix the provider/auth configuration to restore semantic ranking.

If an explicit provider returns query embeddings with a different dimension count from the index, search reports the mismatch instead of comparing those vectors. Verify the provider's model, then rebuild with openclaw memory index --force --agent <agent-id>.

Improving search quality

Two rule-based ranking passes are enabled by default for hybrid search.

Recency decay

Old notes gradually lose ranking weight so recent information surfaces first. With the default 30-day half-life, a note from last month scores at 50% of its original weight, while retaining its pre-decay eligibility. MEMORY.md, USER.md, and undated files under memory/ remain evergreen. Dated YYYY-MM-DD.md and YYYY-MM-DD-<slug>.md files decay at any depth, including session-memory notes and nested dreaming reports.

Session transcript hits use the source activity timestamp captured during indexing. Retained transcript archives use their indexed file modification time. Individual message timestamps remain provenance metadata and do not determine the source's recency weight.

MMR (diversity)

Reduces redundant results. If five notes all mention the same router config, MMR favors a similarly relevant result with different content instead of repeating near-identical snippets. The fixed relevance-biased setting uses lambda 0.7 with Jaccard overlap over snippet tokens. Its local work is O(k²): ordinary defaults request 200 candidates per retrieval leg, for at most 400 unique non-exact candidates before overlap; broader project and identifier searches remain separately capped.

Multimodal memory

With gemini-embedding-2, you can index images and audio alongside Markdown. This only applies to files under memory.search.extraPaths; default memory roots (MEMORY.md, memory/*.md) stay Markdown-only. Search queries remain text, but they match against visual and audio content. See Memory configuration reference for setup.

For exact full-text recall from session transcripts, use sessions_search and then open a result with sessions_history. Session-memory search remains the semantic, experimental complement.

Optionally index session transcripts so memory_search can recall earlier conversations. This is opt-in: set experimental.sessionMemory: true and add "sessions" to sources (default sources is ["memory"]).

Use corpus: "memory" to search only memory notes. Results containing no session transcripts do not load session history or perform session-visibility lookups. For session hits, visibility checks read the matching sessions and their aliases instead of loading the full session catalog. Private recall also checks its anchor conversation and any shared aliases before returning transcript content.

Session hits obey tools.sessions.visibility, which defaults to "all". memory_search still searches the selected agent's indexed corpus; use sessions_search for transcript search across agents on the Gateway. Visible transcripts can include other users' conversations. Cross-agent session access is on by default and governed by tools.agentToAgent; set enabled: false to block ordinary cross-agent access (requester-owned native subagent and ACP child sessions stay reachable under tree or all) or use allow to restrict agent pairs. A per-peer session.dmScope separates DM context but does not restrict transcript access through session tools. Choose explicit "agent" for same-agent recall, "tree" for current plus spawned scope (with an agent-wide exception for main), or "self" for strict current-session recall. Sandbox spawned-only clamps and incognito exclusions still apply.

Troubleshooting

No results? Run openclaw memory status to check the index. If empty, run openclaw memory index --force.

Only keyword matches? Your embedding provider may not be configured. Check openclaw memory status --deep.

Local embeddings time out? ollama, lmstudio, and local use longer provider-owned batch deadlines. Run openclaw memory status --deep to inspect the managed server endpoints before rebuilding the index.

OpenAI-compatible embedding requests honor the caller's deadline, including the longer indexing budget, without an earlier HTTP header or body timeout. Deep status probes make one attempt using the provider's query budget: normally 60 seconds for remote providers or 5 minutes for local, unless the provider supplies its own query budget. Managed server readiness keeps its separate budget. A stalled probe reports memory embedding probe timed out after Ns.

CJK text not found? Rebuild the FTS index with openclaw memory index --force.

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