Task Creation Enhancement: Support for ContextWindow (or userMessage)

acp/README.md

@@ -202,7 +202,11 @@ The Tool resource defines a capability that can be used by an Agent, such as:
 
 ### Task
 
-The Task resource represents a request to an Agent, which starts a conversation.
+The Task resource represents a request to an Agent, which starts a conversation. Tasks can be created in two ways:
+- Using a simple `userMessage` for single-turn queries
+- Using a `contextWindow` containing multiple messages for multi-turn conversations or continuing previous chats
+
+Only one of these methods can be used per Task.
 
 ## License
 

acp/api/v1alpha1/task_types.go

@@ -4,16 +4,39 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
+// Message roles
+const (
+	MessageRoleSystem    = "system"
+	MessageRoleUser      = "user"
+	MessageRoleAssistant = "assistant"
+	MessageRoleTool      = "tool"
+)
+
+// ValidMessageRoles provides a map of valid message roles for validation
+var ValidMessageRoles = map[string]bool{
+	MessageRoleSystem:    true,
+	MessageRoleUser:      true,
+	MessageRoleAssistant: true,
+	MessageRoleTool:      true,
+}
+
 // TaskSpec defines the desired state of Task
 type TaskSpec struct {
 	// AgentRef references the agent that will execute this Task.
 	// +kubebuilder:validation:Required
 	AgentRef LocalObjectReference `json:"agentRef"`
 
 	// UserMessage is the message to send to the agent.
-	// +kubebuilder:validation:Required
-	// +kubebuilder:validation:MinLength=1
-	UserMessage string `json:"userMessage"`
+	// If provided, userMessage will be used and contextWindow must be empty.
+	// +optional
+	UserMessage string `json:"userMessage,omitempty"`
+
+	// ContextWindow provides the initial conversation context when creating a Task.
+	// If provided, contextWindow will be used and userMessage must be empty.
+	// This will be copied to status.ContextWindow, which is the source of truth
+	// for the ongoing conversation.
+	// +optional
+	ContextWindow []Message `json:"contextWindow,omitempty"`
 }
 
 // Message represents a single message in the conversation

acp/config/crd/bases/acp.humanlayer.dev_tasks.yaml

@@ -82,13 +82,81 @@ spec:
                 required:
                 - name
                 type: object
+              contextWindow:
+                description: |-
+                  ContextWindow provides the initial conversation context when creating a Task.
+                  If provided, contextWindow will be used and userMessage must be empty.
+                  This will be copied to status.ContextWindow, which is the source of truth
+                  for the ongoing conversation.
+                items:
+                  description: Message represents a single message in the conversation
+                  properties:
+                    content:
+                      description: Content is the message content
+                      type: string
+                    name:
+                      description: Name is the name of the tool that was called
+                      type: string
+                    role:
+                      description: Role is the role of the message sender (system,
+                        user, assistant, tool)
+                      enum:
+                      - system
+                      - user
+                      - assistant
+                      - tool
+                      type: string
+                    toolCallId:
+                      description: ToolCallID is the unique identifier for this tool
+                        call
+                      type: string
+                    toolCalls:
+                      description: ToolCalls contains any tool calls requested by
+                        this message
+                      items:
+                        description: ToolCall represents a request to call a tool
+                        properties:
+                          function:
+                            description: Function contains the details of the function
+                              to call
+                            properties:
+                              arguments:
+                                description: Arguments contains the arguments to pass
+                                  to the function in JSON format
+                                type: string
+                              name:
+                                description: Name is the name of the function to call
+                                type: string
+                            required:
+                            - arguments
+                            - name
+                            type: object
+                          id:
+                            description: ID is the unique identifier for this tool
+                              call
+                            type: string
+                          type:
+                            description: Type indicates the type of tool call. Currently
+                              only "function" is supported.
+                            type: string
+                        required:
+                        - function
+                        - id
+                        - type
+                        type: object
+                      type: array
+                  required:
+                  - content
+                  - role
+                  type: object
+                type: array
               userMessage:
-                description: UserMessage is the message to send to the agent.
-                minLength: 1
+                description: |-
+                  UserMessage is the message to send to the agent.
+                  If provided, userMessage will be used and contextWindow must be empty.
                 type: string
             required:
             - agentRef
-            - userMessage
             type: object
           status:
             description: TaskStatus defines the observed state of Task

acp/config/example-resources.md

@@ -156,8 +156,21 @@ See the samples file for examples of all supported providers.
 
 - **agentRef:**
   - References an existing Agent (e.g. `"calculator-agent"`)
-- **message:**
+- **userMessage:**
   - The task prompt or request (e.g. `"What is 2 + 2?"`)
+  - Used for single-turn queries
+  - Cannot be used with `contextWindow`
+
+**OR**
+
+- **contextWindow:**
+  - Array of messages representing an initial conversation
+  - Used for multi-turn conversations or continuing previous conversations
+  - Must contain at least one user message
+  - Cannot be used with `userMessage`
+  - If no system message is included, the agent's system message will be prepended
+
+**Sample with contextWindow:** `config/samples/acp_v1alpha1_context_window_task.yaml`
 
 ---
 

acp/config/samples/acp_v1alpha1_context_window_task.yaml

@@ -0,0 +1,16 @@
+apiVersion: acp.humanlayer.dev/v1alpha1
+kind: Task
+metadata:
+  name: context-window-example
+spec:
+  agentRef:
+    name: web-fetch-agent
+  contextWindow:
+    - role: system
+      content: "You are a helpful web assistant."
+    - role: user
+      content: "Can you search the web for info on climate change?"
+    - role: assistant
+      content: "I'll help you research climate change. What specific aspects interest you?"
+    - role: user
+      content: "Tell me about recent developments in renewable energy."

acp/docs/crd-reference.md

@@ -138,12 +138,16 @@ The Task CRD represents a task instance.
 | Field | Type | Description | Required |
 |-------|------|-------------|----------|
 | `agentRef` | LocalObjectReference | Reference to the agent to execute the task | Yes |
-| `userMessage` | string | Message to send to the agent | Yes |
+| `userMessage` | string | Message to send to the agent | No* |
+| `contextWindow` | []Message | Initial conversation context with multiple messages | No* |
+
+*Either `userMessage` or `contextWindow` must be specified, but not both.
 
 ### Status Fields
 
 | Field | Type | Description |
 |-------|------|-------------|
 | `phase` | string | Current phase of execution |
 | `phaseHistory` | []PhaseTransition | History of phase transitions |
-| `contextWindow` | []Message | The conversation context |
+| `contextWindow` | []Message | The conversation context |
+| `userMsgPreview` | string | Preview of the user message or last user message in contextWindow |

acp/internal/controller/task/task_controller.go

@@ -22,6 +22,7 @@ import (
 	"github.com/humanlayer/agentcontrolplane/acp/internal/adapters"
 	"github.com/humanlayer/agentcontrolplane/acp/internal/llmclient"
 	"github.com/humanlayer/agentcontrolplane/acp/internal/mcpmanager"
+	"github.com/humanlayer/agentcontrolplane/acp/internal/validation"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/trace"
@@ -152,54 +153,63 @@ func (r *TaskReconciler) validateTaskAndAgent(ctx context.Context, task *acp.Tas
 	return &agent, ctrl.Result{}, nil
 }
 
+// Helper function for setting validation errors
+func (r *TaskReconciler) setValidationError(ctx context.Context, task *acp.Task, statusUpdate *acp.Task, err error) (ctrl.Result, error) {
+	logger := log.FromContext(ctx)
+	logger.Error(err, "Validation failed")
+	statusUpdate.Status.Ready = false
+	statusUpdate.Status.Status = acp.TaskStatusTypeError
+	statusUpdate.Status.Phase = acp.TaskPhaseFailed
+	statusUpdate.Status.StatusDetail = err.Error()
+	statusUpdate.Status.Error = err.Error()
+	r.recorder.Event(task, corev1.EventTypeWarning, "ValidationFailed", err.Error())
+	if updateErr := r.Status().Update(ctx, statusUpdate); updateErr != nil {
+		logger.Error(updateErr, "Failed to update Task status")
+		return ctrl.Result{}, updateErr
+	}
+	return ctrl.Result{}, err
+}
+
 // prepareForLLM sets up the initial state of a Task with the correct context and phase
 func (r *TaskReconciler) prepareForLLM(ctx context.Context, task *acp.Task, statusUpdate *acp.Task, agent *acp.Agent) (ctrl.Result, error) {
 	logger := log.FromContext(ctx)
 
-	// If we're in Initializing or Pending phase, transition to ReadyForLLM
 	if statusUpdate.Status.Phase == acp.TaskPhaseInitializing || statusUpdate.Status.Phase == acp.TaskPhasePending {
-		statusUpdate.Status.Phase = acp.TaskPhaseReadyForLLM
-		statusUpdate.Status.Ready = true
-
-		if task.Spec.UserMessage == "" {
-			err := fmt.Errorf("userMessage is required")
-			logger.Error(err, "Missing message")
-			statusUpdate.Status.Ready = false
-			statusUpdate.Status.Status = acp.TaskStatusTypeError
-			statusUpdate.Status.Phase = acp.TaskPhaseFailed
-			statusUpdate.Status.StatusDetail = err.Error()
-			statusUpdate.Status.Error = err.Error()
-			r.recorder.Event(task, corev1.EventTypeWarning, "ValidationFailed", err.Error())
-			if updateErr := r.Status().Update(ctx, statusUpdate); updateErr != nil {
-				logger.Error(updateErr, "Failed to update Task status")
-				return ctrl.Result{}, updateErr
-			}
-			return ctrl.Result{}, err
+		if err := validation.ValidateTaskMessageInput(task.Spec.UserMessage, task.Spec.ContextWindow); err != nil {
+			return r.setValidationError(ctx, task, statusUpdate, err)
 		}
 
-		// Set the UserMsgPreview - truncate to 50 chars if needed
-		preview := task.Spec.UserMessage
-		if len(preview) > 50 {
-			preview = preview[:47] + "..."
+		var initialContextWindow []acp.Message
+		if len(task.Spec.ContextWindow) > 0 {
+			initialContextWindow = append([]acp.Message{}, task.Spec.ContextWindow...)
+			hasSystemMessage := false
+			for _, msg := range initialContextWindow {
+				if msg.Role == acp.MessageRoleSystem {
+					hasSystemMessage = true
+					break
+				}
+			}
+			if !hasSystemMessage {
+				initialContextWindow = append([]acp.Message{
+					{Role: acp.MessageRoleSystem, Content: agent.Spec.System},
+				}, initialContextWindow...)
+			}
+		} else {
+			initialContextWindow = []acp.Message{
+				{Role: acp.MessageRoleSystem, Content: agent.Spec.System},
+				{Role: acp.MessageRoleUser, Content: task.Spec.UserMessage},
+			}
 		}
-		statusUpdate.Status.UserMsgPreview = preview
 
-		// Set up the context window
-		statusUpdate.Status.ContextWindow = []acp.Message{
-			{
-				Role:    "system",
-				Content: agent.Spec.System,
-			},
-			{
-				Role:    "user",
-				Content: task.Spec.UserMessage,
-			},
-		}
+		statusUpdate.Status.UserMsgPreview = validation.GetUserMessagePreview(task.Spec.UserMessage, task.Spec.ContextWindow)
+		statusUpdate.Status.ContextWindow = initialContextWindow
+		statusUpdate.Status.Phase = acp.TaskPhaseReadyForLLM
+		statusUpdate.Status.Ready = true
 		statusUpdate.Status.Status = acp.TaskStatusTypeReady
 		statusUpdate.Status.StatusDetail = "Ready to send to LLM"
-		statusUpdate.Status.Error = "" // Clear previous error
-		r.recorder.Event(task, corev1.EventTypeNormal, "ValidationSucceeded", "Task validation succeeded")
+		statusUpdate.Status.Error = ""
 
+		r.recorder.Event(task, corev1.EventTypeNormal, "ValidationSucceeded", "Task validation succeeded")
 		if err := r.Status().Update(ctx, statusUpdate); err != nil {
 			logger.Error(err, "Failed to update Task status")
 			return ctrl.Result{}, err