diff --git a/apis/workflows/v1/automation.proto b/apis/workflows/v1/automation.proto
index 07f45a7..d2530e8 100644
--- a/apis/workflows/v1/automation.proto
+++ b/apis/workflows/v1/automation.proto
@@ -63,7 +63,7 @@ message AutomationPrototype {
     max_bytes: 1024
   }];
   // The task submission to trigger
-  TaskSubmission prototype = 3;
+  SingleTaskSubmission prototype = 3;
 
   // The storage event triggers that will trigger the task
   repeated StorageEventTrigger storage_event_triggers = 4 [(buf.validate.field).repeated.max_items = 32];
diff --git a/apis/workflows/v1/core.proto b/apis/workflows/v1/core.proto
index 574ca59..84dc688 100644
--- a/apis/workflows/v1/core.proto
+++ b/apis/workflows/v1/core.proto
@@ -180,8 +180,8 @@ message Tasks {
   repeated Task tasks = 1;
 }
 
-// TaskSubmission is a message of a task that is just about to be submitted, either by submitting a job or as a subtask.
-message TaskSubmission {
+// SingleTaskSubmission is a message of a task that is just about to be submitted, currently in use by automations.
+message SingleTaskSubmission {
   // The cluster that this task should be run on
   string cluster_slug = 1;
   // The task identifier
@@ -209,7 +209,10 @@ message TaskSubmissions {
   // Concrete instantiations of tasks, grouped by their dependencies and dependants. Each group is uniquely defined by
   // the set of groups that it depends on (dependencies_on_other_groups) and the set of groups that depend on it,
   // (which is implicitly given by the inverse of the dependencies on other groups).
-  repeated TaskSubmissionGroup task_groups = 1;
+  repeated TaskSubmissionGroup task_groups = 1 [(buf.validate.field).repeated = {
+    min_items: 1
+    max_items: 64
+  }];
   // Unique values of cluster slugs, referenced by index in the task instantiations.
   repeated string cluster_slug_lookup = 2;
   // Unique values of task identifiers, referenced by index in the task instantiations.
diff --git a/apis/workflows/v1/job.proto b/apis/workflows/v1/job.proto
index eda15bc..408ae0c 100644
--- a/apis/workflows/v1/job.proto
+++ b/apis/workflows/v1/job.proto
@@ -15,10 +15,12 @@ option features.field_presence = IMPLICIT;
 // SubmitJobRequest submits and schedules a job for execution. The job can have multiple root tasks.
 message SubmitJobRequest {
   // The root tasks for the job.
-  repeated TaskSubmission tasks = 1 [(buf.validate.field).repeated = {
+  repeated SingleTaskSubmission legacy_tasks = 1 [(buf.validate.field).repeated = {
     min_items: 1
     max_items: 64
   }];
+  // The root tasks for the job.
+  TaskSubmissions tasks = 5;
   // The name of the job.
   string job_name = 2 [(buf.validate.field).string.min_len = 1];
   // Tracing information for the job. This is used to propagate tracing information to the workers that execute the job.
@@ -134,7 +136,7 @@ message GetJobPrototypeRequest {
 // A clone prototype of a job.
 message GetJobPrototypeResponse {
   // The root tasks of the job.
-  repeated TaskSubmission root_tasks = 1;
+  repeated SingleTaskSubmission root_tasks = 1;
   // The name of the job.
   string job_name = 2;
 }
@@ -144,7 +146,7 @@ message CloneJobRequest {
   // The ID of the job to clone.
   tilebox.v1.ID job_id = 1 [(buf.validate.field).required = true];
   // The updated root tasks of the job.
-  repeated TaskSubmission root_tasks_overrides = 2 [(buf.validate.field).repeated = {
+  repeated SingleTaskSubmission root_tasks_overrides = 2 [(buf.validate.field).repeated = {
     min_items: 1
     max_items: 64
   }];
diff --git a/apis/workflows/v1/task.proto b/apis/workflows/v1/task.proto
index 2ecd1b6..53b3a85 100644
--- a/apis/workflows/v1/task.proto
+++ b/apis/workflows/v1/task.proto
@@ -36,7 +36,7 @@ message ComputedTask {
   // If not set, the display message specified upon task submission will be kept.
   string display = 2;
   // A list of sub-tasks that the just computed task spawned.
-  repeated TaskSubmission legacy_sub_tasks = 3 [
+  repeated SingleTaskSubmission legacy_sub_tasks = 3 [
     deprecated = true,
     (buf.validate.field).repeated.max_items = 64
   ];