PureCloudPlatformClientV2 handles the predictive routing payload serialization differently when you pass a custom modelVersion parameter. First, the Studio flow triggers on a queue configuration change. Next, the REST Proxy action hits /api/v2/routing/predictive/queues/${queueId}/configurations with a PUT verb. The request body includes {"strategy": "PREDICTIVE", "modelVersion": "v2.1", "confidenceThreshold": 0.85}. The SDK expects that modelVersion string to match the cluster baseline exactly. The cluster is currently running v2.0.3. The response comes back as a 400 Bad Request. The error payload contains {"error": "PREDICTIVE_ROUTING_MODEL_VERSION_MISMATCH", "message": "Supplied model version v2.1 does not match cluster baseline v2.0.3"}. The SDK doesn’t catch the mismatch during the initial handshake. It just passes the raw response to the next node. The flow then routes to a SNIPPET action that parses the response.body using JSON.parse(data). The snippet logs the error code to the context variable predictive.errorCode. The next step checks if predictive.errorCode == "PREDICTIVE_ROUTING_MODEL_VERSION_MISMATCH". The condition evaluates to true. The flow branches to a retry loop with a 15000 millisecond delay.
The timestamp drift on the London edge is throwing off the cache invalidation window. Three queues are stuck in a retry loop right now. The console is empty except for the retry counters. Swapping the confidenceThreshold to 0.75 and leaving modelVersion blank doesn’t help. The API defaults to latest but it’s still throwing the same mismatch error. The flow logs show the request headers include Authorization: Bearer <token> and Content-Type: application/json. The SDK version pinned in the script is genesys-cloud-purecloud-platform-client-v2@128.0.0.
The predictive routing engine seems to ignore the fallback logic when the Studio context variable predictive.enabled flips to true. The queue capacity drops to zero during the retry phase. Callers get routed to the overflow queue instead. The REST action timeout is set to 30000 milliseconds. Nothing changes. The payload structure matches the Swagger spec exactly.
// Fetch the active configuration first to grab the correct modelVersion
const queueConfigs = await platformClient.queueConfigurations.getQueueConfigurations(queueId);
const targetConfig = queueConfigs.entities.find(c => c.strategy === 'PREDICTIVE');
const updatePayload = {
strategy: "PREDICTIVE",
// Use the version string returned by the GET request, never hardcode this.
modelVersion: targetConfig.modelVersion,
strategyConfiguration: {
confidenceThreshold: 0.85
}
};
// Apply the update via the SDK method
await platformClient.queueConfigurations.putQueueConfiguration(targetConfig.id, updatePayload);
The 400 PREDICTIVE_ROUTING_MODEL_VERSION_MISMATCH error almost always means you’re injecting a hardcoded string that the backend can’t resolve against the active model registry. The SDK’s putQueueConfiguration method expects the payload to align strictly with the schema returned by getQueueConfigurations. Passing a raw modelVersion like "v2.1" without verifying it exists in the tenant’s routing/predictive/models list triggers the mismatch immediately. You’ll want to fetch the valid modelVersion first. If the Studio retry loop keeps hammering the proxy, the queue enters a degraded state fast. Check the modelVersion property on the response object. It’s usually v1.0 or a specific UUID depending on your tenant setup. Don’t guess the version string. The serialization logic in PureCloudPlatformClientV2 strips unknown properties, so a mismatched version string gets rejected before it hits the database. Also ensure the strategyConfiguration object isn’t nested incorrectly. The API expects the confidenceThreshold inside strategyConfiguration, not at the root level of the payload. Make sure the service account has routing:queue:edit scope. Without that, you’ll get a 403 instead of the version mismatch, which masks the actual serialization issue.
const queueConfigs = await platformClient.queueConfigurations.getQueueConfigurations(queueId);
const currentConfig = queueConfigs.entities.find(c => c.strategy === 'PREDICTIVE');
// Never hardcode the version. Sync it dynamically to avoid the 400 mismatch.
const safePayload = {
...originalPayload,
modelVersion: currentConfig.modelVersion,
etag: currentConfig.etag // Required for the PUT operation
};
await platformClient.queueConfigurations.putQueueConfigurations(queueId, safePayload);
PureCloudPlatformClientV2 doesn’t automatically resolve the version string during a PUT operation, which is exactly why you’re seeing that mismatch error. When the Studio retry loop fires, it keeps sending the hardcoded modelVersion: "v2.1" back to the /api/v2/routing/predictive/queues/${queueId}/configurations endpoint. The platform rejects it because the internal schema already bumped to v2.2 after your first patch. You’ll need to break the retry cycle and inject a validation step before the REST proxy action executes.
First, grab the current configuration using await platformClient.queueConfigurations.getQueueConfigurations(queueId). Then compare the returned modelVersion against your payload. If they don’t align, update the object in memory with payload.modelVersion = response.entities[0].modelVersion before passing it to the SDK. Hardcoding that string guarantees a state drift situation. You should also add a simple exponential backoff to the Studio retry logic, otherwise the proxy will just hammer the API until you hit the 429 rate limit. Rate limits will catch up to you eventually. Just kill the retry loop.