diff --git a/realis.go b/realis.go
index 7f08943..d8a477e 100644
--- a/realis.go
+++ b/realis.go
@@ -60,7 +60,7 @@ type RealisConfig struct {
 func NewClient(config RealisConfig) Realis {
 
 	httpTrans := (config.transport).(*thrift.THttpClient)
-	httpTrans.SetHeader("User-Agent", "GoRealis v0.1")
+	httpTrans.SetHeader("User-Agent", "GoRealis v1.0.4")
 
 	protocolFactory := thrift.NewTJSONProtocolFactory()
 
@@ -140,12 +140,12 @@ func (r realisClient) KillInstances(key *aurora.JobKey, instances ...int32) (*au
 		instanceIds[instId] = true
 	}
 
-	response, err := r.client.KillTasks(key, instanceIds)
+	resp, err := r.client.KillTasks(key, instanceIds)
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending Kill command to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 // Sends a kill message to the scheduler for all active tasks under a job.
@@ -157,13 +157,13 @@ func (r realisClient) KillJob(key *aurora.JobKey) (*aurora.Response, error) {
 	}
 
 	if len(instanceIds) > 0 {
-		response, err := r.client.KillTasks(key, instanceIds)
+		resp, err := r.client.KillTasks(key, instanceIds)
 
 		if err != nil {
 			return nil, errors.Wrap(err, "Error sending Kill command to Aurora Scheduler")
 		}
 
-		return response, nil
+		return response.ResponseCodeCheck(resp)
 	} else {
 		return nil, errors.New("No tasks in the Active state")
 	}
@@ -171,43 +171,43 @@ func (r realisClient) KillJob(key *aurora.JobKey) (*aurora.Response, error) {
 
 // Sends a create job message to the scheduler with a specific job configuration.
 func (r realisClient) CreateJob(auroraJob Job) (*aurora.Response, error) {
-	response, err := r.client.CreateJob(auroraJob.JobConfig())
+	resp, err := r.client.CreateJob(auroraJob.JobConfig())
 
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending Create command to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 func (r realisClient) ScheduleCronJob(auroraJob Job) (*aurora.Response, error) {
-	response, err := r.client.ScheduleCronJob(auroraJob.JobConfig())
+	resp, err := r.client.ScheduleCronJob(auroraJob.JobConfig())
 
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending Cron Job Schedule message to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 func (r realisClient) DescheduleCronJob(key *aurora.JobKey) (*aurora.Response, error) {
-	response, err := r.client.DescheduleCronJob(key)
+	resp, err := r.client.DescheduleCronJob(key)
 
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending Cron Job De-schedule message to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 func (r realisClient) StartCronJob(key *aurora.JobKey) (*aurora.Response, error) {
-	response, err := r.client.StartCronJob(key)
+	resp, err := r.client.StartCronJob(key)
 
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending Start Cron Job  message to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 // Restarts specific instances specified
@@ -218,12 +218,12 @@ func (r realisClient) RestartInstances(key *aurora.JobKey, instances ...int32) (
 		instanceIds[instId] = true
 	}
 
-	response, err := r.client.RestartShards(key, instanceIds)
+	resp, err := r.client.RestartShards(key, instanceIds)
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending Restart command to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 // Restarts all active tasks under a job configuration.
@@ -235,13 +235,13 @@ func (r realisClient) RestartJob(key *aurora.JobKey) (*aurora.Response, error) {
 	}
 
 	if len(instanceIds) > 0 {
-		response, err := r.client.RestartShards(key, instanceIds)
+		resp, err := r.client.RestartShards(key, instanceIds)
 
 		if err != nil {
 			return nil, errors.Wrap(err, "Error sending Restart command to Aurora Scheduler")
 		}
 
-		return response, nil
+		return response.ResponseCodeCheck(resp)
 	} else {
 		return nil, errors.New("No tasks in the Active state")
 	}
@@ -250,13 +250,13 @@ func (r realisClient) RestartJob(key *aurora.JobKey) (*aurora.Response, error) {
 // Update all tasks under a job configuration. Currently gorealis doesn't support for canary deployments.
 func (r realisClient) StartJobUpdate(updateJob *UpdateJob, message string) (*aurora.Response, error) {
 
-	response, err := r.client.StartJobUpdate(updateJob.req, message)
+	resp, err := r.client.StartJobUpdate(updateJob.req, message)
 
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending StartJobUpdate command to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 // Abort Job Update on Aurora. Requires the updateId which can be obtained on the Aurora web UI.
@@ -264,26 +264,26 @@ func (r realisClient) AbortJobUpdate(
 	updateKey aurora.JobUpdateKey,
 	message string) (*aurora.Response, error) {
 
-	response, err := r.client.AbortJobUpdate(&updateKey, message)
+	resp, err := r.client.AbortJobUpdate(&updateKey, message)
 
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending AbortJobUpdate command to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 // Scale up the number of instances under a job configuration using the configuration for specific
 // instance to scale up.
 func (r realisClient) AddInstances(instKey aurora.InstanceKey, count int32) (*aurora.Response, error) {
 
-	response, err := r.client.AddInstances(&instKey, count)
+	resp, err := r.client.AddInstances(&instKey, count)
 
 	if err != nil {
 		return nil, errors.Wrap(err, "Error sending AddInstances command to Aurora Scheduler")
 	}
 
-	return response, nil
+	return response.ResponseCodeCheck(resp)
 }
 
 func (r realisClient) FetchTaskConfig(instKey aurora.InstanceKey) (*aurora.TaskConfig, error) {
@@ -312,6 +312,7 @@ func (r realisClient) FetchTaskConfig(instKey aurora.InstanceKey) (*aurora.TaskC
 			instKey.JobKey.Name)
 	}
 
+	// Currently, instance 0 is always picked
 	return tasks[0].AssignedTask.Task, nil
 }
 
@@ -322,7 +323,7 @@ func (r realisClient) JobUpdateDetails(updateQuery aurora.JobUpdateQuery) (*auro
 		return nil, errors.Wrap(err, "Unable to get job update details")
 	}
 
-	return resp, nil
+	return response.ResponseCodeCheck(resp)
 }
 func (r realisClient) RollbackJobUpdate(key aurora.JobUpdateKey, message string) (*aurora.Response, error) {
 
@@ -331,5 +332,5 @@ func (r realisClient) RollbackJobUpdate(key aurora.JobUpdateKey, message string)
 		return nil, errors.Wrap(err, "Unable to roll back job update")
 	}
 
-	return resp, nil
+	return response.ResponseCodeCheck(resp)
 }
diff --git a/response/response.go b/response/response.go
index b64e665..c9da05e 100644
--- a/response/response.go
+++ b/response/response.go
@@ -16,7 +16,9 @@
 package response
 
 import (
+	"bytes"
 	"github.com/rdelval/gorealis/gen-go/apache/aurora"
+	"github.com/pkg/errors"
 )
 
 // Get key from a response created by a StartJobUpdate call
@@ -31,3 +33,24 @@ func JobUpdateDetails(resp *aurora.Response) []*aurora.JobUpdateDetails {
 func ScheduleStatusResult(resp *aurora.Response) *aurora.ScheduleStatusResult_ {
 	return resp.GetResult_().GetScheduleStatusResult_()
 }
+
+func ResponseCodeCheck(resp *aurora.Response) (*aurora.Response, error) {
+	if resp.GetResponseCode() != aurora.ResponseCode_OK {
+		return resp, errors.New(CombineMessage(resp))
+	}
+
+	return resp, nil
+}
+
+// Based on aurora client: src/main/python/apache/aurora/client/base.py
+func CombineMessage(resp *aurora.Response) string {
+	var buffer bytes.Buffer
+	for _, detail := range resp.GetDetails() {
+		buffer.WriteString(detail.GetMessage() + ", ")
+	}
+
+	if buffer.Len() > 0 {
+		buffer.Truncate(buffer.Len()-2) // Get rid of trailing comma + space
+	}
+	return buffer.String()
+}