●Change8

Migrating to MemGPT 0.12.1

Version 0.12.1 introduces 2 breaking changes. This guide details how to update your code.

Released: 10/9/2025

2
Breaking Changes
4
Migration Steps
4
Affected Symbols

⚠️ Check Your Code

If you use any of these symbols, you need to read this guide:

get_folder_by_namesources routessummarization_agentclient.folders.list

Breaking Changes

●Issue #1

`get_folder_by_name` is deprecated and removed. Use `client.folders.list(name=...)` instead.

✓Solution

Replace calls to `get_folder_by_name` with `client.folders.list(name=...)`.

●Issue #2

All routes previously named `sources` have been renamed to `folders`.

✓Solution

Update any code referencing routes that used the `sources` naming convention to use `folders` instead.

Migration Steps

  1. 1
    Review code for usage of deprecated API `get_folder_by_name` and replace it with `client.folders.list(name=...)`.
  2. 2
    Update any code referencing routes that used the `sources` naming convention to use `folders` instead.
  3. 3
    For new agents, create them using the `letta_v1_agent` architecture.
  4. 4
    If you relied on agent heartbeats for periodic execution, implement this logic via custom prompting or scheduling, as heartbeats are removed in the new architecture.

Release Summary

This release introduces the major `letta_v1_agent` architecture, offering broader provider compatibility and simpler control flow, alongside new features like Human-in-the-Loop and Parallel Tool Calling. It also deprecates and renames several older API endpoints.

Need More Details?

View the full release notes and all changes for MemGPT 0.12.1.

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