diff --git a/pkg/agent/loop.go b/pkg/agent/loop.go
index 0d98e22..1c0916a 100644
--- a/pkg/agent/loop.go
+++ b/pkg/agent/loop.go
@@ -42,6 +42,7 @@ type Config struct {
 	OnIteration        OnIterationHook
 	ToolTimeout        time.Duration
 	ChatTemplateKwargs map[string]any // passed to the LLM provider (e.g. Qwen enable_thinking)
+	AgentsMD           string         // discovered AGENTS.md content, folded into the system prompt
 }
 
 // Iteration represents a single cycle of the agent loop.
@@ -230,7 +231,7 @@ func (l *Loop) RunStream(ctx context.Context, input string, history ...llm.Messa
 }
 
 func (l *Loop) buildInitialMessages(input string, history []llm.Message) []llm.Message {
-	systemPrompt := persona.AssembleSystemPrompt(l.cfg.Persona, "")
+	systemPrompt := persona.AssembleSystemPrompt(l.cfg.Persona, l.cfg.AgentsMD)
 	messages := make([]llm.Message, 0, len(history)+2)
 	messages = append(messages, llm.Message{Role: llm.RoleSystem, Content: systemPrompt})
 	messages = append(messages, history...)
diff --git a/pkg/agent/loop_test.go b/pkg/agent/loop_test.go
index e81f128..4c59bcf 100644
--- a/pkg/agent/loop_test.go
+++ b/pkg/agent/loop_test.go
@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"iter"
+	"strings"
 	"testing"
 	"time"
 
@@ -116,6 +117,30 @@ func TestRun_NoToolCalls(t *testing.T) {
 	}
 }
 
+func TestRun_IncludesAgentsMD(t *testing.T) {
+	var capturedSystemPrompt string
+	mockClient := &mockLLM{
+		generateFunc: func(ctx context.Context, req llm.CompletionRequest) (llm.CompletionResponse, error) {
+			capturedSystemPrompt = req.Messages[0].Content
+			return llm.CompletionResponse{Content: "done"}, nil
+		},
+	}
+
+	loop := New(Config{
+		LLM:      mockClient,
+		Persona:  persona.DefaultPersona(),
+		Tools:    tools.NewRegistry(),
+		AgentsMD: "Never edit go.mod directly.",
+	})
+
+	if _, err := loop.Run(context.Background(), "Hello"); err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !strings.Contains(capturedSystemPrompt, "Never edit go.mod directly.") {
+		t.Errorf("expected system prompt to include AGENTS.md content, got %q", capturedSystemPrompt)
+	}
+}
+
 func TestRun_ToolCalls(t *testing.T) {
 	registry := tools.NewRegistry()
 	registry.Register(tools.Tool{
diff --git a/pkg/persona/persona.go b/pkg/persona/persona.go
index 0d83982..c092b23 100644
--- a/pkg/persona/persona.go
+++ b/pkg/persona/persona.go
@@ -79,8 +79,8 @@ func AssembleSystemPrompt(p Persona, agentsMD string) string {
 	return strings.Join(parts, "\n\n")
 }
 
-// discoverAgentsMD walks up the directory tree looking for AGENTS.md files.
-func discoverAgentsMD(root string) string {
+// DiscoverAgentsMD walks up the directory tree looking for AGENTS.md files.
+func DiscoverAgentsMD(root string) string {
 	var parts []string
 	current := root
 
diff --git a/pkg/persona/persona_test.go b/pkg/persona/persona_test.go
index 86a3ffc..ed60fea 100644
--- a/pkg/persona/persona_test.go
+++ b/pkg/persona/persona_test.go
@@ -45,9 +45,9 @@ func TestDiscoverAgentsMD(t *testing.T) {
 	agentsPath := filepath.Join(tmpDir, "AGENTS.md")
 	os.WriteFile(agentsPath, []byte("test instructions"), 0644)
 
-	result := discoverAgentsMD(tmpDir)
+	result := DiscoverAgentsMD(tmpDir)
 	if !contains(result, "test instructions") {
-		t.Error("expected discoverAgentsMD to find AGENTS.md")
+		t.Error("expected DiscoverAgentsMD to find AGENTS.md")
 	}
 }