Unsuccessfully sign-in to Kiro with builder ID

Option 1: Disable Network Privacy Filters (iCloud Private Relay)

MacOS Sequoia includes enhanced privacy features that can interfere with cross-domain authentication tokens. Disabling these temporarily often resolves the redirect loop.

• Navigate to System Settings > [Your Name] > iCloud > Private Relay.
• Toggle Private Relay to Off.
• Additionally, in Safari Settings > Advanced, uncheck "Use advanced tracking and fingerprinting protection".
• Restart your browser and attempt the login again.

source: https://support.apple.com/en-us/102022

Option 2: Amazon Q CLI

If the web-based login continues to fail, you can bypass the standard browser-initiated handshake by using the command line. This triggers a "Device Flow" which is more resilient to browser redirect issues.

• Open your Terminal.
• Run the following command to reach the subscription management page directly:

q chat

• Inside the interactive session, type:

/subscribe --manage

• Copy the URL provided in the terminal and paste it into a Private/Incognito window. This forces a clean authentication session that often bypasses the Sequoia local cache loop.

see: https://docs.aws.amazon.com/amazonq/latest/qdeveloper-ug/q-admin-setup-unsubscribe.html#unsubscribe-builder-id

In many cases, this type of sign-in issue is caused by network-level interference. We’ve seen it resolved by disabling any active VPN or local antivirus/security software, as these can block or alter authentication redirects.

Suggested Troubleshooting Steps:

• Disable VPN (if enabled)
• Temporarily turn off antivirus or endpoint security tools
• Try from a different machine
• Switch to a different network (e.g., use a mobile hotspot)

These steps help isolate whether the issue is related to your local environment or network configuration.