Merge pull request #471 from multica-ai/agent/j/959392dd

feat: support multiple agents running on same issue

server/internal/handler/daemon.go

@@ -536,17 +536,22 @@ func (h *Handler) ListTaskMessages(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, http.StatusOK, resp)
 }
 
-// GetActiveTaskForIssue returns the currently running task for an issue, if any.
+// GetActiveTaskForIssue returns all currently active tasks for an issue.
+// Returns { tasks: [...] } array (may be empty).
 func (h *Handler) GetActiveTaskForIssue(w http.ResponseWriter, r *http.Request) {
 	issueID := chi.URLParam(r, "id")
 
 	tasks, err := h.Queries.ListActiveTasksByIssue(r.Context(), parseUUID(issueID))
-	if err != nil || len(tasks) == 0 {
-		writeJSON(w, http.StatusOK, map[string]any{"task": nil})
-		return
+	if err != nil {
+		tasks = nil
 	}
 
-	writeJSON(w, http.StatusOK, map[string]any{"task": taskToResponse(tasks[0])})
+	resp := make([]AgentTaskResponse, len(tasks))
+	for i, t := range tasks {
+		resp[i] = taskToResponse(t)
+	}
+
+	writeJSON(w, http.StatusOK, map[string]any{"tasks": resp})
 }
 
 // CancelTask cancels a running or queued task by ID.

server/internal/handler/issue.go

@@ -549,9 +549,12 @@ func (h *Handler) shouldEnqueueOnComment(ctx context.Context, issue db.Issue) bo
 		return false
 	}
 	// Coalescing queue: allow enqueue when a task is running (so the agent
-	// picks up new comments on the next cycle) but skip if a pending task
-	// already exists (natural dedup for rapid-fire comments).
-	hasPending, err := h.Queries.HasPendingTaskForIssue(ctx, issue.ID)
+	// picks up new comments on the next cycle) but skip if this agent already
+	// has a pending task (natural dedup for rapid-fire comments).
+	hasPending, err := h.Queries.HasPendingTaskForIssueAndAgent(ctx, db.HasPendingTaskForIssueAndAgentParams{
+		IssueID: issue.ID,
+		AgentID: issue.AssigneeID,
+	})
 	if err != nil || hasPending {
 		return false
 	}

server/pkg/db/generated/agent.sql.go

@@ -109,6 +109,7 @@ WHERE id = (
       AND NOT EXISTS (
           SELECT 1 FROM agent_task_queue active
           WHERE active.issue_id = atq.issue_id
+            AND active.agent_id = atq.agent_id
             AND active.status IN ('dispatched', 'running')
       )
     ORDER BY atq.priority DESC, atq.created_at ASC
@@ -118,10 +119,10 @@ WHERE id = (
 RETURNING id, agent_id, issue_id, status, priority, dispatched_at, started_at, completed_at, result, error, created_at, context, runtime_id, session_id, work_dir, trigger_comment_id
 `
 
-// Claims the next queued task for an agent, enforcing per-issue serialization:
-// a task is only claimable when no other task for the same issue is already
-// dispatched or running. This guarantees serial execution within an issue
-// while allowing parallel execution across different issues.
+// Claims the next queued task for an agent, enforcing per-(issue, agent) serialization:
+// a task is only claimable when no other task for the same issue AND same agent is
+// already dispatched or running. This allows different agents to work on the same
+// issue in parallel while preventing a single agent from running duplicate tasks.
 func (q *Queries) ClaimAgentTask(ctx context.Context, agentID pgtype.UUID) (AgentTaskQueue, error) {
 	row := q.db.QueryRow(ctx, claimAgentTask, agentID)
 	var i AgentTaskQueue

server/pkg/db/queries/agent.sql

@@ -75,10 +75,10 @@ SELECT * FROM agent_task_queue
 WHERE id = $1;
 
 -- name: ClaimAgentTask :one
--- Claims the next queued task for an agent, enforcing per-issue serialization:
--- a task is only claimable when no other task for the same issue is already
--- dispatched or running. This guarantees serial execution within an issue
--- while allowing parallel execution across different issues.
+-- Claims the next queued task for an agent, enforcing per-(issue, agent) serialization:
+-- a task is only claimable when no other task for the same issue AND same agent is
+-- already dispatched or running. This allows different agents to work on the same
+-- issue in parallel while preventing a single agent from running duplicate tasks.
 UPDATE agent_task_queue
 SET status = 'dispatched', dispatched_at = now()
 WHERE id = (
@@ -87,6 +87,7 @@ WHERE id = (
       AND NOT EXISTS (
           SELECT 1 FROM agent_task_queue active
           WHERE active.issue_id = atq.issue_id
+            AND active.agent_id = atq.agent_id
             AND active.status IN ('dispatched', 'running')
       )
     ORDER BY atq.priority DESC, atq.created_at ASC