Description

The "Transaction Added" event was missing the address_alert_response field, which made it difficult to analyze transaction flows by address security status from the initial event.

Solution
Added address_alert_response to the initial "Transaction Added" event. The field includes:

• The actual scan result if already cached (e.g., 'Benign', 'Malicious')
• 'Loading' if the scan is still in progress
• 'not_applicable' when scanning cannot be performed (security alerts disabled, no to address, or unsupported chain)

The useTrustSignalMetrics hook continues to update the event fragment with the final value once the scan completes.

Changelog

CHANGELOG entry: null

Manual testing steps

1. Start the mock Segment server:

node development/mock-segment.js

2. Start the extension with Segment enabled:

yarn start

3. Trigger a transaction (e.g., send ETH or interact with a dApp)
4. In the mock Segment terminal, observe the "Transaction Added" event
5. Verify address_alert_response is present with one of:
   • 'Loading' (scan in progress)
   • 'Benign', 'Malicious', 'Warning' (scan result)
   • 'not_applicable' (security alerts disabled or unsupported chain)
6. Approve or reject the transaction
7. Verify the "Transaction Finalized" event has the final address_alert_response value (should no longer be 'Loading')

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Extension Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.