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A minimal guide to enabling conversational memory with sessions. When you use the same session_id across searches, Cognee remembers previous questions and answers, enabling contextually aware follow-up questions.

Before You Start

Code in Action

import asyncio
import cognee
from cognee import SearchType

async def main():
    # Prepare knowledge base
    await cognee.add([
        "Alice moved to Paris in 2010. She works as a software engineer.",
        "Bob lives in New York. He is a data scientist.",
        "Alice and Bob met at a conference in 2015."
    ])
    await cognee.cognify()

    # First search - starts a new session (default user is used when none is passed)
    result1 = await cognee.search(
        query_type=SearchType.GRAPH_COMPLETION,
        query_text="Where does Alice live?",
        session_id="conversation_1"
    )
    print("First answer:", result1[0])

    # Follow-up search - uses conversation history
    result2 = await cognee.search(
        query_type=SearchType.GRAPH_COMPLETION,
        query_text="What does she do for work?",
        session_id="conversation_1"  # Same session
    )
    print("Follow-up answer:", result2[0])
    # The LLM knows "she" refers to Alice from previous context

    # Different session - no memory of previous conversation
    result3 = await cognee.search(
        query_type=SearchType.GRAPH_COMPLETION,
        query_text="What does she do for work?",
        session_id="conversation_2"  # New session
    )
    print("New session answer:", result3[0])
    # This won't know who "she" refers to

asyncio.run(main())
This example works with either Redis or Filesystem adapter. Configure your chosen adapter in the Before you start section above.

What Just Happened

Step 1: Prepare Knowledge Base

await cognee.add([
    "Alice moved to Paris in 2010. She works as a software engineer.",
    "Bob lives in New York. He is a data scientist.",
    "Alice and Bob met at a conference in 2015."
])
await cognee.cognify()
Before you can search with sessions, you need to have data in your knowledge base. Use cognee.add() to ingest data and cognee.cognify() to build the knowledge graph.

Step 2: Use Session ID in Searches

result = await cognee.search(
    query_type=SearchType.GRAPH_COMPLETION,
    query_text="Where does Alice live?",
    session_id="conversation_1"
)
The session_id parameter creates or continues a conversation thread. All searches with the same session_id share conversation history.

Step 3: Follow-up Questions

result = await cognee.search(
    query_type=SearchType.GRAPH_COMPLETION,
    query_text="What does she do for work?",
    session_id="conversation_1"  # Same session
)
When you use the same session_id, Cognee automatically includes previous Q&A turns in the LLM prompt, enabling contextual follow-up questions.

Step 4: Multiple Sessions

# Session 1
await cognee.search(query_text="Question 1", session_id="session_1")
await cognee.search(query_text="Follow-up", session_id="session_1")

# Session 2 (independent)
await cognee.search(query_text="Question 1", session_id="session_2")
Each session_id maintains its own conversation history. Sessions are isolated from each other.

Advanced Usage

Use meaningful session IDs to organize conversations:
# User-specific sessions
await cognee.search(query_text="...", session_id=f"user_{user_id}_chat")

# Topic-specific sessions
await cognee.search(query_text="...", session_id="project_planning")
await cognee.search(query_text="...", session_id="bug_discussion")
Session IDs are arbitrary strings—use whatever naming scheme fits your application.
Sessions do not expire automatically. They persist until the cache is cleared. To clear sessions, use cognee.prune.prune_system(..., cache=True) or wipe your cache backend (e.g. Redis keys or the filesystem cache directory).Sessions can also be persisted into the knowledge graph via the session persistence pipeline, which converts cached Q&A history into searchable graph nodes.
If you omit session_id and caching is enabled, Cognee uses the session ID default_session and still stores each search turn there. To scope conversations explicitly, pass a session_id.
Use cognee.session.get_session() to retrieve stored Q&A entries for a session. Entries are returned in chronological order (oldest first). Use entries[-1] for the most recent entry. If the session does not exist or the cache backend is unavailable, this call returns an empty list instead of raising an error.
session_id
str
default:"default_session"
Identifier of the session to retrieve. It must match the session_id previously passed to cognee.search().
last_n
Optional[int]
default:"None"
Maximum number of most-recent entries to return. When None, all stored entries are returned.
user
Optional[User]
default:"None"
User that owns the session. When None, Cognee resolves it from the current session context or falls back to the default user.
Returns List[SessionQAEntry], which may be empty.
import cognee

entries = await cognee.session.get_session(session_id="conversation_1", last_n=5)
for entry in entries:
    print(f"[{entry.time}] Q: {entry.question}")
    print(f"           A: {entry.answer}")
    print(f"  feedback score: {entry.feedback_score}")
Every Q&A entry stored in the session cache contains a context field. Depending on how the completion was generated, this field may be empty or may contain a stored summary of the retrieved context for that turn. You can inspect it programmatically when reading session history.The include_context flag:
get_session_manager() is an internal, lower-level API rather than the usual SDK entry point. Prefer cognee.session.get_session() unless you specifically need formatted history control such as include_context.
SessionManager.get_session() and SessionManager.format_entries() both accept include_context: bool (default True). When True, a CONTEXT: line is included for each entry in the formatted history string; when False, it is omitted.This flag is not exposed on cognee.search() or cognee.session.get_session(). If you need it, use the lower-level SessionManager directly.Additional information:
import cognee

entries = await cognee.session.get_session(session_id="my_session", last_n=5)
for entry in entries:
    print("Q:", entry.question)
    print("Stored context:", entry.context)   # may be empty or a stored summary
    print("A:", entry.answer)
No. When Cognee builds conversation history for the LLM during cognee.search(), it uses include_context=False internally — previous questions and answers are included in the prompt, but the stored context from those earlier turns is omitted. Fresh graph context is retrieved for the current query only. This keeps prompts compact and avoids re-sending large context blobs.
If your use-case requires the LLM to see stored context from a prior turn — for example to trace provenance or build a richer prompt — use the lower-level SessionManager to retrieve formatted history with include_context=True, then pass that history to your own LLM call.
from cognee.infrastructure.session.get_session_manager import get_session_manager
from cognee.modules.users.methods import get_default_user

user = await get_default_user()
sm = get_session_manager()

# Formatted string with CONTEXT included per entry (default)
history_with_context = await sm.get_session(
    user_id=str(user.id),
    session_id="my_session",
    formatted=True,
    include_context=True,    # includes CONTEXT: line for each Q&A turn
)
Omitting session_id does not disable session storage: Cognee still writes to default_session when caching is on. To avoid storing any session data, set CACHING=false or ensure no cache backend is available. The system gracefully handles missing cache backends; searches run without conversational memory.
Sessions only affect these search types: GRAPH_COMPLETION, RAG_COMPLETION, TRIPLET_COMPLETION. Other modes (CHUNKS, SUMMARIES, etc.) do not use or write session history. Cognee includes up to the last 10 session entries when building conversation history. For multi-tenant or background jobs, pass an explicit user so the default user is not used.
Cognee can record approximate LLM usage per session for session-scoped completion flows. This is most relevant when you use recall in a conversational pattern and want to inspect prompt/completion volume over time.What is trackedWhen an LLM completion is generated inside an active session scope, Cognee accumulates these values on the session record:
  • tokens_in — estimated prompt tokens
  • tokens_out — estimated completion tokens
  • cost_usd — estimated spend using Cognee’s built-in pricing table
These values are approximate. Cognee estimates tokens with a character-based heuristic rather than exact provider-reported usage, so use them for monitoring and rough cost estimation rather than invoice-grade billing.When counts are recorded
  • Session tracking depends on caching being available.
  • If you omit session_id, Cognee still uses default_session rather than disabling session usage tracking.
  • The tracked counts reflect session-scoped completion calls, not every LLM-capable step in the broader ingestion pipeline.
For broader guidance on where LLM calls happen outside session accounting:
  • See Recall for retrieval and only_context=True
  • See Cognify for ingestion-time call counts
Session visibility in the HTTP APISession-listing and session-detail HTTP endpoints return sessions visible to the caller at read time. That includes sessions owned by the requesting user, sessions owned by child agents whose parent_user_id matches the requesting user’s id, and sessions visible through dataset read permissions.Sessions remain stored under the user that actually created them, so the user_id on each session_records row is unchanged. Aggregate totals such as stats and cost-by-model therefore include usage from child agents when those sessions are visible to the parent. See Users for how to create agent users with parent_user_id.Reading usage via the HTTP API
GET /api/v1/sessions
GET /api/v1/sessions/{session_id}
GET /api/v1/sessions/stats?range=30d
GET /api/v1/sessions/cost-by-model?range=30d
  • GET /api/v1/sessions lists sessions visible to the caller
  • GET /api/v1/sessions/{session_id} returns per-session fields such as tokens_in, tokens_out, and cost_usd
  • GET /api/v1/sessions/stats?range=30d returns aggregate totals for 24h, 7d, 30d, or all
  • GET /api/v1/sessions/cost-by-model?range=30d breaks usage down by model

Sessions and Caching

Understand how sessions work conceptually

Search Basics

Learn about search parameters and types

Setup Configuration

Configure cache adapters and providers