vercel/ai · error · Error

ACP lifecycle state belongs to sandbox ${JSON.stringify(expe

Error message

ACP lifecycle state belongs to sandbox ${JSON.stringify(expectedSandboxId)}, not ${JSON.stringify(sandboxId)}.

What it means

Error "ACP lifecycle state belongs to sandbox ${JSON.stringify(expectedSandboxId)}, not ${JSON.stringify(sandboxId)}." thrown in vercel/ai.

Source

Thrown at packages/harness-acp/src/v1/acp-v1-lifecycle.ts:89

  if (lifecycleData.implementationIdentity !== implementationIdentity) {
    throw new Error(
      'ACP lifecycle state is incompatible with the configured implementation.',
    );
  }
  if (
    lifecycleData.authenticationProfile?.digest !== authenticationProfile.digest
  ) {
    throw new Error(
      'ACP lifecycle state is incompatible with the configured authentication profile.',
    );
  }
  const expectedSandboxId = lifecycleData.bridge?.sandboxId;
  if (
    expectedSandboxId != null &&
    sandboxId != null &&
    expectedSandboxId !== sandboxId
  ) {
    throw new Error(
      `ACP lifecycle state belongs to sandbox ${JSON.stringify(
        expectedSandboxId,
      )}, not ${JSON.stringify(sandboxId)}.`,
    );
  }
}

View on GitHub (pinned to 69428b1f8b)

When it happens

Trigger: Thrown at packages/harness-acp/src/v1/acp-v1-lifecycle.ts:89 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of vercel/ai@69428b1f8b (2026-08-30). Data as JSON: /api/errors/2fb2cd09f3349153. Report an issue: GitHub.