botserver/docs/src/chapter-05/keyword-clear-kb.md

CLEAR_KB

Clear knowledge base collections from the current session context.

Syntax

CLEAR_KB kb_name

or

CLEAR_KB

Parameters

Parameter	Type	Description
kb_name	String	Optional. Name of specific knowledge base to remove. If omitted, clears all KBs

Description

The CLEAR_KB keyword removes knowledge base collections from the current session's context. This is useful for:

• Switching between different knowledge domains
• Reducing context size for performance
• Preventing irrelevant KB interference
• Managing memory usage in long-running sessions

When called without parameters, it clears all active knowledge bases. When called with a specific KB name, it only removes that collection.

Examples

Clear Specific Knowledge Base

USE_KB "product-docs"
USE_KB "user-manual"
' Later, remove just one
CLEAR_KB "product-docs"
' user-manual remains active

Clear All Knowledge Bases

USE_KB "docs"
USE_KB "faqs"
USE_KB "policies"
' Clear everything
CLEAR_KB
' No KBs active now

Conditional KB Management

IF topic = "technical" THEN
    CLEAR_KB
    USE_KB "engineering-docs"
ELSE
    CLEAR_KB "engineering-docs"
    USE_KB "general-docs"
END IF

Knowledge Base Rotation

' Use KB for initial query
USE_KB "current-year-data"
answer = FIND "quarterly results"
TALK answer

' Switch to historical data
CLEAR_KB "current-year-data"
USE_KB "historical-data"
historical = FIND "previous year results"
TALK historical

Return Value

Returns a boolean indicating success:

• true: Knowledge base(s) successfully cleared
• false: Operation failed or KB not found

Session Context

The CLEAR_KB command affects only the current user session. Other sessions maintain their own KB contexts independently.

Memory Management

Clearing knowledge bases:

• Removes vector collection references from session
• Frees up context window space
• Does NOT delete the actual KB data (only removes from active context)
• Reduces memory footprint of the session

Error Handling

• Silently succeeds if specified KB is not currently loaded
• Returns false if KB name is invalid format
• Logs warning if clearing fails due to system constraints

Performance Considerations

1. Context Size: Clearing unused KBs reduces token usage in LLM calls
2. Query Speed: Fewer active KBs means faster semantic search
3. Memory: Each KB consumes memory for index caching
4. Relevance: Too many KBs can introduce irrelevant results

Best Practices

1. Clear Before Switching: Always clear old KBs before loading new ones for different domains
2. Periodic Cleanup: In long conversations, periodically clear unused KBs
3. Domain Separation: Don't mix unrelated knowledge domains
4. Check Before Clear: Optionally check if KB is loaded before clearing

Example of good practice:

' Clean switch between domains
CLEAR_KB
IF customer_type = "enterprise" THEN
    USE_KB "enterprise-docs"
    USE_KB "sla-policies"
ELSE
    USE_KB "standard-docs"
END IF

Related Keywords

• USE_KB - Load knowledge base collections
• ADD_WEBSITE - Add website content to KB
• FIND - Search within loaded KBs
• LLM - Query LLM with KB context

Implementation Details

Located in src/basic/keywords/clear_kb.rs

The implementation:

• Maintains KB references in session state
• Uses HashSet for efficient KB tracking
• Integrates with Qdrant vector store
• Handles concurrent access safely
• Updates session metrics for monitoring