Persistent "state syncing error: key not found" / Agent terminated — isolated to one workspace, survives full workspaceStorage reset

Google Antigravity
1

Environment:

  • Antigravity IDE version/commit: 2.1.1 (build 1.107.0, user setup)
  • Electron: e0b7a2bcf575cfba10528c4e7c10bd3ce2d7769a (2026-06-17)
  • OS: Windows
  • Account: Google Pro plan (signed in via Google Auth)

Symptom:
One specific workspace (“buisiness-design”) consistently fails with
“Agent terminated due to error” on every single prompt, regardless of model
(tested with Claude Opus, Claude 3.5, Gemini 3.5 Flash). Other workspaces on
the same machine/account work completely normally with the same models.

Relevant log lines (Antigravity IDE output channel):
Failed to get OAuth token: error getting token source from auth provider:
state syncing error: key not found
Cache(availableModels): Singleflight refresh failed: error getting token
source: state syncing error: key not found

Troubleshooting already attempted (none resolved it):

  1. Retry / new conversation / switching models
  2. Full sign-out and sign-in
  3. “Antigravity: Reset onboarding” command
  4. Opened the same project folder fresh (Open Folder, not via .code-workspace)
  5. Located and fully reset the workspace-specific storage folder at
    %APPDATA%\Antigravity IDE\User\workspaceStorage\ (state.vscdb was
    regenerated from scratch, confirmed empty/new) — error still occurs
    immediately on the very first message in the freshly reset workspace
  6. Confirmed the project’s “Always On” agent rules are not the cause — an
    unaffected workspace loads equivalent-sized Always On rules without issue

Given that a complete reset of both the workspace storage and the auth
session did not resolve it, this appears to be a backend/account-state
issue tied to this specific workspace rather than anything fixable locally.

Debug info attached below.
Trajectory ID: bf589be9-7a29-4ab8-af49-70d2cc48…
Error: agent executor error: proto: field google.cloud.aiplatform.master.Part.text contains invalid UTF-8: proto: field google.cloud.aiplatform.master.Part.text contains invalid UTF-8
(1) attached stack trace
– stack trace:
| google3/third_party/gemini_coder/framework/executor/agentexecutor/agentexecutor.(*AgentExecutor).Run
| third_party/gemini_coder/framework/executor/agentexecutor/agentexecutor.go:330
| […repeated from below…]
Wraps: (2) agent executor error
Wraps: (3) tags: map[stream_receive_count:0 streaming_duration:0s]
Wraps: (4) attached stack trace
– stack trace:
| google3/third_party/gemini_coder/framework/generator/generator.(*streamResponseHandler).processStream
| third_party/gemini_coder/framework/generator/stream_handler.go:351
| google3/third_party/gemini_coder/framework/generator/generator.(*PlannerGenerator).attemptGenerate
| third_party/gemini_coder/framework/generator/planner_generator.go:467
| google3/third_party/gemini_coder/framework/generator/generator.(*PlannerGenerator).generateWithAPIRetry
| third_party/gemini_coder/framework/generator/planner_generator.go:296
| google3/third_party/gemini_coder/framework/generator/generator.(*PlannerGenerator).generateWithModelOutputRetry
| third_party/gemini_coder/framework/generator/planner_generator.go:156
| google3/third_party/gemini_coder/framework/generator/generator.(*PlannerGenerator).Generate
| third_party/gemini_coder/framework/generator/planner_generator.go:92
| google3/third_party/gemini_coder/framework/executor/executor.(*Executor).runInvocation
| third_party/gemini_coder/framework/executor/executor.go:467
| google3/third_party/gemini_coder/framework/executor/executor.(*Executor).runExecution
| third_party/gemini_coder/framework/executor/executor.go:369
| google3/third_party/gemini_coder/framework/executor/executor.(*Executor).Execute
| third_party/gemini_coder/framework/executor/executor.go:342
| google3/third_party/gemini_coder/framework/executor/agentexecutor/agentexecutor.(*AgentExecutor).Run
| third_party/gemini_coder/framework/executor/agentexecutor/agentexecutor.go:305
| google3/third_party/jetski/cortex/cortex.(*CascadeManager).executeOne.func1
| third_party/jetski/cortex/cascade_manager.go:1602
| google3/third_party/jetski/cortex/cortex.(*CascadeManager).executeOne.func2
| third_party/jetski/cortex/cascade_manager.go:1613
| google3/third_party/jetski/cortex/utils/background.(*Pool).Go.func2
| third_party/jetski/cortex/utils/background.go:121
| google3/go/context/detach.Go.func1
| go/context/detach.go:250
| runtime.goexit
| third_party/go/gc/src/runtime/asm_amd64.s:1736
Wraps: (5) proto: field google.cloud.aiplatform.master.Part.text contains invalid UTF-8
Wraps: (6) proto: field google.cloud.aiplatform.master.Part.text contains invalid UTF-8
Wraps: (7) protobuf error
Error types: (1) *withstack.withStack (2) *errutil.withPrefix (3) *go_utils.withTags (4) *withstack.withStack (5) *errutil.withPrefix (6) *errors.prefixError (7) *errors.errorString