---
title: 'Fix Login Redirect Loops and Session Bugs Without Guesswork'
description: 'A plain-language guide to troubleshooting login loops, cookie issues, and session state bugs using KaBOOM Agentic Devtools.'
canonical: https://gokaboom.dev/articles/fix-login-redirect-loops-and-session-bugs/
docs_version: 'v0.8.1'
docs_channel: 'latest'
last_verified_version: '0.8.0'
last_verified_date: 'Fri Mar 06 2026 00:00:00 GMT+0000 (Coordinated Universal Time)'
normalized_tags: ['authentication', 'debugging', 'cookies', 'sessions', 'articles', 'fix', 'login', 'redirect', 'loops', 'session', 'bugs']
related_guides: ['/guides/debug-webapps/', '/guides/api-validation/', '/reference/observe/']
---

If your app keeps bouncing users between “Sign in” and “Dashboard,” you likely have a session bug.

A **session** is how your app remembers that a user is logged in. Sessions are often backed by **cookies** (small browser data tokens). Cookie basics: https://developer.mozilla.org/en-US/docs/Web/HTTP/Cookies

Here is a beginner-safe way to debug this with **KaBOOM Agentic Devtools**.

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## Quick Terms

- **Session**: Login memory for a user.
- **Cookie**: Browser storage used for auth state.
- **Application Programming Interface (API)**: Structured way browser and server exchange data. https://developer.mozilla.org/en-US/docs/Glossary/API
- **Redirect loop**: Page A sends to B, B sends back to A forever.

## The Problem You Are Solving

You want to answer:

“Why does login not stick after successful sign-in?”

## Step-by-Step with KaBOOM Agentic Devtools

### Step 1. Record the redirect path

```js
observe({what: "history"})
observe({what: "network_waterfall", status_min: 300, status_max: 399, limit: 30})
```

This shows the exact chain of redirects.

### Step 2. Inspect cookie/session storage

```js
observe({what: "storage", storage_type: "cookies"})
observe({what: "storage", storage_type: "local"})
observe({what: "storage", storage_type: "session"})
```

Check whether auth data exists and survives navigation.

### Step 3. Verify login API response

```js
observe({what: "network_bodies", url: "/auth", limit: 20})
```

Confirm response status and expected fields.

### Step 4. Replay and compare before/after fixes

```js
configure({what: "recording_start"})
configure({what: "recording_stop", recording_id: "rec-login"})
configure({what: "playback", recording_id: "rec-login"})
configure({what: "log_diff", original_id: "rec-before", replay_id: "rec-after"})
```

## Common Root Causes

- Cookie set on wrong domain/path.
- Auth token saved in one store but read from another.
- Frontend route guard runs before session state is ready.
- Backend returns success but no usable token.

## Image and Diagram Callouts

> [Image Idea] Redirect chain ladder diagram (`/login` -> `/callback` -> `/login`).

> [Image Idea] Side-by-side cookie table: “broken state” vs “working state”.

## You’re Doing Advanced Debugging Now

Session bugs feel random. They are not random. With **KaBOOM Agentic Devtools**, you can see the chain, storage state, and network truth in one place.