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Memory

This docs was updated at: 2026-02-23

com.paragon.agents.Memory  ยท  Interface

Interface for agent long-term memory storage with user isolation.

Memory provides persistent storage for agent knowledge that persists across sessions. All operations are scoped by userId to ensure data isolation between users.

Memory is exposed to the agent as tools via MemoryTool. The userId is passed securely by the developer in Agent.interact(input, context, userId), NOT by the LLM, to prevent prompt injection attacks.

Example usage:

Memory storage = InMemoryMemory.create();
Agent agent = Agent.builder()
    .addMemoryTools(storage)  // Adds memory as tools
    .build();
// userId passed by developer - secure!
agent.interact("Remember my preference", context, "user-123");

See Also

  • MemoryEntry
  • MemoryTool
  • InMemoryMemory

Since: 1.0

Methods

add

void add(@NonNull String userId, @NonNull MemoryEntry entry)

Adds a new memory entry for a user.

Parameters

Name Description
userId the user ID (for isolation)
entry the memory to add

add

default void add(@NonNull String userId, @NonNull String content)

Adds a memory with just content for a user.

Parameters

Name Description
userId the user ID
content the memory content

retrieve

List<MemoryEntry> retrieve(@NonNull String userId, @NonNull String query, int limit)

Retrieves memories relevant to a query for a user.

Parameters

Name Description
userId the user ID
query the search query
limit maximum number of memories to return

Returns

list of relevant memories, ordered by relevance

update

void update(@NonNull String userId, @NonNull String id, @NonNull MemoryEntry entry)

Updates an existing memory entry for a user.

Parameters

Name Description
userId the user ID
id the memory ID to update
entry the new memory content

Throws

Type Condition
IllegalArgumentException if memory with ID doesn't exist for this user

delete

boolean delete(@NonNull String userId, @NonNull String id)

Deletes a memory by ID for a user.

Parameters

Name Description
userId the user ID
id the memory ID to delete

Returns

true if memory was deleted, false if not found

all

List<MemoryEntry> all(@NonNull String userId)

Returns all stored memories for a user.

Parameters

Name Description
userId the user ID

Returns

list of all memories for this user

size

int size(@NonNull String userId)

Returns the number of stored memories for a user.

Parameters

Name Description
userId the user ID

Returns

memory count for this user

clear

void clear(@NonNull String userId)

Clears all memories for a user.

Parameters

Name Description
userId the user ID

clearAll

void clearAll()

Clears all memories for all users.