langchain-ai/langgraph
1
0
Fork 0
mirror of https://github.com/langchain-ai/langgraph.git synced 2026-07-15 12:35:43 -04:00
Code Issues 314 Packages Projects Releases 17 Wiki Activity

[PR #6635] fix(prebuilt): remove self-loop edge in graph visualization when using post_model_hook #5180

New Issue
Closed
opened 2026-02-20 17:51:20 -05:00 by yindo · 0 comments
yindo commented 2026-02-20 17:51:20 -05:00
Owner
Copy Link
Copy Source

Original Pull Request: https://github.com/langchain-ai/langgraph/pull/6635

State: closed
Merged: No

Fix for #6516

Description

Fix graph visualization showing a confusing self-loop arrow from post_model_hook back to agent (or pre_model_hook) when using response_format with post_model_hook.

The issue was caused by:

  1. Including entrypoint in post_model_hook_paths initialization
  2. An unreachable condition in post_model_hook_router that returned entrypoint when the last message was a ToolMessage

This condition never triggers because after tools execute, they route to the agent which produces an AIMessage before reaching post_model_hook_router.

Issue

Fixes #6516

Dependencies

None

**Original Pull Request:** https://github.com/langchain-ai/langgraph/pull/6635 **State:** closed **Merged:** No --- Fix for #6516 ## Description Fix graph visualization showing a confusing self-loop arrow from `post_model_hook` back to `agent` (or `pre_model_hook`) when using `response_format` with `post_model_hook`. The issue was caused by: 1. Including `entrypoint` in `post_model_hook_paths` initialization 2. An unreachable condition in `post_model_hook_router` that returned `entrypoint` when the last message was a `ToolMessage` This condition never triggers because after tools execute, they route to the agent which produces an `AIMessage` before reaching `post_model_hook_router`. ## Issue Fixes #6516 ## Dependencies None
yindo added the pull-request label 2026-02-20 17:51:20 -05:00
yindo closed this issue 2026-02-20 17:51:20 -05:00
Sign in to join this conversation.
No Branch/Tag Specified
Branches Tags
Labels
Clear labels
agents
awaiting author revision
bug
change
chat models
checkpointer
ci
code quality
code quality
dependencies
documentation
drawing
duplicate
enhancement
good first issue
help wanted
invalid
maintainer
meta
missing information
not maintained by langchain
open-swe-auto
open-swe-max
open-swe-max-auto
pending
performance
pull-request
Mirrored from GitHub Pull Request
 question
requires design
sdk
server
stale
studio
tests
type checking
usage question
v0.5
v1.1
No Label pull-request
Milestone
No items
No Milestone
Projects
Clear projects
No project
Assignees
Clear assignees
yindo
No Assignees
1 Participants
Notifications
Due Date
No due date set.
Dependencies

No dependencies set.

Reference: langchain-ai/langgraph#5180
Delete Branch "%!s()"

Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?