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cognee.recall()

Description

recall() is the main retrieval entry point in Cognee v1.0.
  • It auto-routes queries by default when you do not specify query_type. Routing is rule-based (no LLM call) and falls back to HYBRID_COMPLETION when no cue matches — see Auto-routing behavior for the full cue-to-search-type mapping and when to override.
  • It can search the permanent graph, session memory, or both.
  • It returns RecallResponse items sourced from graph retrieval, session retrieval, or both depending on the request.
For the full behavior walkthrough, see Recall and Search Basics.

Prerequisites

recall() only reads from memory that already exists — it does not initialize anything on its own. Populate memory first with remember() (or the legacy add() + cognify() sequence). The first ingestion run creates the relational, vector, and graph databases and the default user.
Calling recall() before any data has been ingested raises RecallPreconditionError (a CogneeValidationError, HTTP 422) with the message “Recall prerequisites not met: no database/default user found.” It is triggered by the underlying DatabaseNotCreatedError (“The database has not been created yet. Please call await setup() first.”) or UserNotFoundError. The fix is to run remember() (or add() + cognify()) first.

Parameters

str
required
Natural-language query to run against memory.
SearchType | None
default:"None"
Forces a specific retrieval strategy instead of using auto-routing. Leaving it unset when no usable LLM is configured resolves to SearchType.CHUNKS (plain vector search over chunks) instead of a completion, because nothing could write a completion answer. This is decided by LLM availability alone — the same key rule the provider preflight applies — and never by which extractor built the graph: a GLiNER-built graph answers completions normally as long as a key is present. An explicit query_type still selects any search type.
list[str] | None
default:"None"
Restricts graph retrieval to the named datasets. Dataset names are resolved only against datasets owned by the current user. When both datasets and dataset_ids are omitted, retrieval spans every dataset the current user has read access to — not just a single default dataset. Pass this to narrow the search to specific datasets.
list[UUID] | None
default:"None"
Restricts graph retrieval by dataset UUIDs instead of names. Use this for shared datasets that the current user can access but did not create. When provided, this takes precedence over datasets and the name-to-UUID lookup is skipped. Leaving both datasets and dataset_ids unset searches all of the user’s readable datasets.
int
default:"15"
Maximum number of results to return.
bool
default:"True"
When True, Cognee chooses a retrieval strategy automatically if query_type is not set, using the rule-based query router. Set it to False to always use HYBRID_COMPLETION. An explicit query_type always takes precedence over routing. With no usable LLM configured, the no-query_type default is CHUNKS under either setting — see query_type above.
str | list[str] | None
default:"None"
Which sources retrieval reads from. Accepts a single value or a list:
  • "graph" — the permanent knowledge graph.
  • "session" — session-cache Q&A history, matched by keyword.
  • "trace" — recorded agent traces, matched by keyword across function name, parameters, return value, and error message. See Agent Session Traces.
  • "session_context" — the session’s active guidance, rendered read-only for the profile named by context_profile. Serving it never stamps or ages an entry.
  • "all" — expands to graph, session, trace, and session_context.
  • "auto" — the default when scope is omitted. Resolves to graph alone when there is no session_id, or when session_id is combined with an explicit query_type; otherwise to session plus graph. It never selects trace or session_context — ask for those by name.
"tools" and "code" are explicit opt-in only: neither "auto" nor "all" includes them, so name them yourself (scope=["all", "tools"] works). An unrecognized name raises ValueError. "graph_context" is a deprecated alias for "graph".

Additional keyword options

recall() accepts only the parameters documented above — it has no catch-all **kwargs. Passing an unsupported keyword such as node_type raises TypeError: recall() got an unexpected keyword argument 'node_type'. To restrict retrieval to specific nodes or node sets, use node_name (a list[str]). node_type is a legacy search() parameter and is not exposed on recall().

Structured output with response_model

Pass a Pydantic model class to get a validated, parsed answer instead of free text — each result carries the validated payload as a dict in its structured field. All completion-style search types support it (GRAPH_COMPLETION and its variants except GRAPH_SUMMARY_COMPLETION, RAG_COMPLETION, TRIPLET_COMPLETION, HYBRID_COMPLETION, TEMPORAL, AGENTIC_COMPLETION):
response_model is shorthand for retriever_specific_config={"response_model": ...} — Cognee folds the parameter into the config before dispatching, so the dict form still works. Pass it in one place: supplying the same model class through both is allowed, but different classes raise CogneeValidationError (HTTP 422).
Remote mode. A Python class cannot cross the HTTP boundary, so against a remote server (see serve()) the SDK forwards response_model.model_json_schema() as the response_schema field of POST /api/v1/recall, and the server rebuilds a validation model from it. Only the schema’s structure travels — custom validators and value constraints are not enforced server-side; rehydrate on the client (NLPFacts.model_validate(results[0].structured)) when you need them. See Search & Recall — response_schema for the supported schema subset and rejection rules.

Return value

recall() returns a list of RecallResponse items. Depending on the request, results may come from session memory, permanent graph retrieval, or both. These items are Pydantic objects, not plain dictionaries — read fields with attribute access (result.text), not result.get("text") or result["text"]. Calling .get() on a result raises AttributeError: 'ResponseGraphEntry' object has no attribute 'get'. The concrete type of each item is set by its source field (import from cognee.modules.recall.types.RecallResponse):

Warming-up marker

Before running graph retrieval, recall() checks how far the target datasets got through a Cognee pipeline. This check is a single indexed relational query — it never spins up a graph or vector engine. It classifies the datasets into three readiness states: For the two cold states the graph lane returns immediately, with a marker instead of a graph search plus an LLM call that could only come back empty:
When the last ingestion for those datasets errored instead, the marker explains the failure rather than claiming memory is still warming up:
If you branch on source, add a "system" case — code that previously saw an empty list for a cold dataset now sees a one-item list carrying this marker. text is populated so consumers that just render text still display something sensible. If you branch on status, treat build_failed as a failure to surface to the user, not as a transient “still warming up” state that will resolve on its own: it only clears once a graph-writing run succeeds. Details and exceptions:
  • The marker only appears when graph is the sole source. In a multi-source recall (for example a session-scoped call that reads both session memory and the graph), a cold graph contributes [] instead, so the other sources — and the tools on_empty fallback — behave exactly as if graph retrieval had returned nothing.
  • only_context=True bypasses the check and always runs normal retrieval, since those callers expect context rather than a marker.
  • Populated datasets are unaffected. A dataset with a completed graph-writing run reads as warm. So does one that has only been add()-ed but not yet cognified — staged-only datasets fail safe to warm, and a failed add() never produces a build_failed marker, since staging says nothing about the graph.
  • A build still in flight reads as warm. The never-built verdict requires that no pipeline run exists at all, so once a first cognify() has started — a background run, for example — recall runs a normal search that comes back empty rather than returning a memory_warming_up marker.
  • Only warm verdicts are cached. Both cold states are re-probed on every recall, so the first recall after a successful rebuild sees the truth immediately.
  • The check fails open. A probe or configuration error falls through to a normal search, so it can never block a real answer.
  • It can be turned off with RECALL_WARMUP_SHORTCIRCUIT=false (or cognee.config.set("recall_warmup_shortcircuit", False)), which restores the previous behavior exactly. See Recall warm-up for that variable and its two companions.

Skill gate

When a query reads like a request for a procedure, recall() also looks for matching skill playbooks and appends them to the results as "skills" entries. The gate is a fixed set of weighted regexes — no LLM call, no I/O — that fires on phrasings such as how do I …, steps to …, walk me through, playbook, runbook, checklist, workflow, or the word skill. An operational verb alone (set up, install, configure, deploy, migrate, troubleshoot, and similar) is too weak to fire the gate by itself and only counts alongside one of those phrasings. A negated phrase does not count, using the same suppression as the query router. When it fires, recall() starts a SKILLS search for up to three skills concurrently with the main retrieval and appends the hits after the other sources. Each hit is a ResponseSkillEntry whose skill dict holds the skill’s metadata only — the procedure body stays behind the load_skill tool or GET /api/v1/skills/{skill_id}.
  • Additive and fail-safe. The main lanes never wait on the gate, it never replaces or blocks the main answer, and any error in the lookup contributes nothing rather than failing the recall. A dataset with no skills ingested yet simply adds no entries.
  • Single-dataset only. Skills are scoped per dataset, so the gate runs only when exactly one dataset is targeted through datasets or dataset_ids. Otherwise it is skipped silently.
  • Skipped when it would be redundant. It does not run when "graph" is not in scope, when only_context=True, or when query_type is already SKILLS or AGENTIC_COMPLETION.
  • It can be turned off with SKILL_GATE_ENABLED=false.

Source provenance in metadata

For chunk and summary results (CHUNKS, CHUNKS_LEXICAL, SUMMARIES), the metadata dict carries stable source identifiers so you can map a result back to the data you ingested and inspect the exact cited chunk. Only the keys present in the underlying payload are included: Completion-style results (e.g. GRAPH_COMPLETION) carry an empty metadata dict unless include_references=True (see include_references); then metadata.evidence lists structured references to what was placed in the LLM context, and the same ids are also surfaced inline in the Evidence: block. RAG_COMPLETION bullets are rendered as - chunk N of document NAME (data_id: …, chunk_id: …): "snippet", built from the retrieved chunk payloads with no DB migration required. GRAPH_COMPLETION bullets are rendered as - chunk N of document NAME (data_id: …, chunk_id: …) with no snippet, resolved through the edge-evidence sidecar, which needs Alembic revision f3a7b9c1d2e4 on an existing deployment.
The text_result, context_result, objects_result, user_prompt_result, and system_prompt_result keys come from the legacy search(verbose=True) API, which returns plain dicts. recall() does not produce those keys — an only_context call’s system prompt is on the item’s own system_prompt field. For a graph-backed recall item, result.text is the display-ready value. result.raw preserves the normalized payload for that item; for completion-style searches, it is not the same thing as objects_result.

Relevance in score

CHUNKS, SUMMARIES, and SKILLS results carry the retriever’s own relevance number in score (and, for chunks and summaries, under raw["score"] alongside the rest of the payload), so you can rank or fuse results across retrievers instead of trusting return order alone. The value is the raw backend distance, not a normalized similarity — cosine distance for the built-in vector adapters — so a lower number is a better match, and the range depends on the vector store you run. Do not compare a score across two different backends, and do not read it as a 0–1 confidence. score is None for search types whose payload carries no numeric score: completion-style search types, and CHUNKS_LEXICAL — whose BM25 ranking orders results but does not populate this field. Branch on score is not None before doing arithmetic with it.
For the full breakdown of session-hit shapes, graph-backed wrappers, and per-search-type payloads, see Recall — What recall returns.

Examples

With backend access control enabled, datasets=["name"] only resolves dataset names owned by the current user. If a dataset was created by Alice and shared with Bob, Bob should query it with dataset_ids=[shared_id], not datasets=["name"].
See also SearchType and search() when you need lower-level retrieval control.