Agent fails to migrate and gets unhealthy when migrated with `Replace Token` agent options enabled.

[amolnater-qasource]

Kibana version:

VERSION: 9.2.0-SNAPSHOT
BUILD: 90020
COMMIT: 567e6e28df4a7adb8b6a883f4e255c058ab346f2

Preconditions:

1. 9.2.0-SNAPSHOT Kibana cloud environment should be available.
2. An agent should be installed with Agent policy.

Steps to reproduce:

1. Navigate to Agents tab
2. Click Actions>Migrate Agent and add new Fleet Server URL and token for the agent policy.
3. Under Advanced options enable Replace Token toggle.
4. Observe Agent fails to migrate and gets unhealthy.

Expected behavior:
Agent should migrate to new cluster when migrated with Replace Token agent options enabled.

Agent Logs:

elastic-agent-diagnostics-2025-09-05T09-19-44Z-00.zip

Agent JSON:

ip-172-31-88-136-agent-details.json.zip

Screen Capture:

Screen.Recording.2025-09-05.at.2.49.02.PM.mov

Related Feature:
elastic/kibana#217619

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[amolnater-qasource]

@muskangulati-qasource Please review.

[muskangulati-qasource]

Secondary review is Done for this ticket!

[ebeahan]

@michalpristas please have a look here when you have a chance.

[michalpristas]

seems like replace token is passed as bool instead of value.
will debug and update UI issue

[amolnater-qasource]

Hi Team,
While testing this feature we have observed that this issue is also reproducible when Staging option is enabled.

Observations:

• Agent also fails to migrate and gets unhealthy when migrated with Staging agent options enabled.

Build details:
VERSION: 9.2.0-SNAPSHOT
BUILD: 90233
COMMIT: 074fae506562aafc0fb02a4bec5876b5d666100d

Screen Capture:

Screen.Recording.2025-09-08.at.12.29.14.PM.mov

JSON:
ip-172-31-88-136-agent-details.json.zip

Logs:
elastic-agent-diagnostics-2025-09-08T06-59-48Z-00.zip

Please let us know if anything else is required from our end.
Thanks!!

[michalpristas]

that's right/ will make it part of a single fix

[michalpristas]

for reference elastic/kibana#235752