### Is there an existing issue for this? - [x] I have searched the existing issues ### Current Behavior If you use cloud identity, like Google, AWS, or Azure instance identity for your prebuilt workspace agent, then we fail to connect to the `reinit` endpoint, and the agent will never reinitialize after being claimed. ### Relevant Log Output ```shell t.go:106: 2025-07-31 12:23:27.369 [info] cli: stderr: 2025-07-31 12:23:27.369 [debu] cli: waiting for agent reinitialization instructions t.go:106: 2025-07-31 12:23:27.369 [info] cli: connecting to coderd t.go:106: 2025-07-31 12:23:27.369 [info] cli: stderr: 2025-07-31 12:23:27.369 [info] cli: connecting to coderd t.go:106: 2025-07-31 12:23:27.369 [debu] cli: sdk request method=POST url=http://localhost:53956/api/v2/workspaceagents/google-instance-identity body="" t.go:106: 2025-07-31 12:23:27.369 [info] cli: stderr: 2025-07-31 12:23:27.369 [debu] cli: sdk request method=POST url=http://localhost:53956/api/v2/workspaceagents/google-instance-identity body="" t.go:106: 2025-07-31 12:23:27.369 [info] cli: http server listening addr=127.0.0.1:2113 name=debug t.go:106: 2025-07-31 12:23:27.369 [info] cli: stderr: 2025-07-31 12:23:27.369 [info] cli: http server listening addr=127.0.0.1:2113 name=debug t.go:106: 2025-07-31 12:23:27.369 [info] cli: http server listening addr=127.0.0.1:2112 name=prometheus t.go:106: 2025-07-31 12:23:27.369 [info] cli: stderr: 2025-07-31 12:23:27.369 [info] cli: http server listening addr=127.0.0.1:2112 name=prometheus t.go:106: 2025-07-31 12:23:27.369 [debu] coderd: GET host=localhost:53956 path=/api/v2/workspaceagents/me/reinit proto=HTTP/1.1 remote_addr=127.0.0.1 start="2025-07-31T16:23:27.3697711+04:00" took=0s status_code=401 latency_ms=0 request_id=03aea236-c257-4ca3-b96d-7240e1ed4d77 t.go:109: 2025-07-31 12:23:27.370 [erro] cli: failed to wait for agent reinitialization instructions error="GET http://localhost:53956/api/v2/workspaceagents/me/reinit: unexpected status code 401: Cookie \"coder_session_token\" must be provided.: Try logging in using 'coder login'." t.go:106: 2025-07-31 12:23:27.370 [info] cli: stderr: 2025-07-31 12:23:27.370 [erro] cli: failed to wait for agent reinitialization instructions error="GET http://localhost:53956/api/v2/workspaceagents/me/reinit: unexpected status code 401: Cookie \"coder_session_token\" must be provided.: Try logging in using 'coder login'." t.go:106: 2025-07-31 12:23:27.387 [debu] coderd: POST host=localhost:53956 path=/api/v2/workspaceagents/google-instance-identity proto=HTTP/1.1 remote_addr=127.0.0.1 start="2025-07-31T16:23:27.3703069+04:00" requestor_name=System took=17.1539ms status_code=200 latency_ms=17 request_id=df5a870a-c1a7-49fe-b1db-fa2f844a5c91 t.go:106: 2025-07-31 12:23:27.387 [debu] cli: sdk response method=POST url=http://localhost:53956/api/v2/workspaceagents/google-instance-identity status=200 body="" trace_id="" span_id="" t.go:106: 2025-07-31 12:23:27.387 [info] cli: stderr: 2025-07-31 12:23:27.387 [debu] cli: sdk response method=POST url=http://localhost:53956/api/v2/workspaceagents/google-instance-identity status=200 body="" trace_id="" span_id="" ``` ### Expected Behavior Prebuilds should work correctly with cloud instance identity, including handling being claimed. ### Steps to Reproduce 1. Use cloud instance identity for your prebuild ### Environment - Host OS: all - Coder version: `main` ### Additional Context _No response_