diff --git a/nestapi_test.go b/nestapi_test.go
new file mode 100644
index 0000000..acef3f4
--- /dev/null
+++ b/nestapi_test.go
@@ -0,0 +1,126 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+// newTestNestServer is newTestServer plus a message store.
+func newTestNestServer(t *testing.T) (*httptest.Server, *Server) {
+	t.Helper()
+	ts, s := newTestServer(t, DefaultGuardrails(), time.Minute)
+	ms, err := LoadMessageStore(filepath.Join(t.TempDir(), "messages"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	s.WithMessages(ms)
+	return ts, s
+}
+
+func newNest(t *testing.T, ts *httptest.Server, name, crows string) string {
+	t.Helper()
+	code, out := post(t, ts.URL+"/api/nests", `{"name":"`+name+`","crows":[`+crows+`]}`)
+	if code != http.StatusCreated {
+		t.Fatalf("create nest: %d %v", code, out)
+	}
+	return out["nest_id"].(string)
+}
+
+func nestMessages(t *testing.T, ts *httptest.Server, nestID string) []map[string]any {
+	t.Helper()
+	resp, err := http.Get(ts.URL + "/api/nests/" + nestID + "/messages")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("get messages: %d", resp.StatusCode)
+	}
+	var msgs []map[string]any
+	if err := json.NewDecoder(resp.Body).Decode(&msgs); err != nil {
+		t.Fatal(err)
+	}
+	return msgs
+}
+
+// awaitMessages polls until the nest has at least n messages or the deadline passes.
+func awaitMessages(t *testing.T, ts *httptest.Server, nestID string, n int) []map[string]any {
+	t.Helper()
+	deadline := time.Now().Add(2 * time.Second)
+	for {
+		msgs := nestMessages(t, ts, nestID)
+		if len(msgs) >= n || time.Now().After(deadline) {
+			return msgs
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+}
+
+func TestPostMessageToNest(t *testing.T) {
+	ts, _ := newTestNestServer(t)
+	id := newNest(t, ts, "Lab", `"Hugin"`)
+	code, msg := post(t, ts.URL+"/api/nests/"+id+"/messages", `{"author":"owner","text":"hello, flock"}`)
+	if code != http.StatusCreated {
+		t.Fatalf("want 201, got %d %v", code, msg)
+	}
+	if msg["kind"] != "say" || msg["author"] != "owner" || msg["text"] != "hello, flock" {
+		t.Fatalf("bad record: %v", msg)
+	}
+	if msg["msg_id"] != id+"-1" {
+		t.Fatalf("want msg_id %s-1, got %v", id, msg["msg_id"])
+	}
+	got := nestMessages(t, ts, id)
+	if len(got) != 1 || got[0]["text"] != "hello, flock" {
+		t.Fatalf("log missing the message: %v", got)
+	}
+}
+
+func TestPostMessageUnknownNest(t *testing.T) {
+	ts, _ := newTestNestServer(t)
+	code, out := post(t, ts.URL+"/api/nests/nope/messages", `{"author":"owner","text":"hi"}`)
+	if code != http.StatusNotFound || out["message"] == nil {
+		t.Fatalf("want 404 with message, got %d %v", code, out)
+	}
+}
+
+func TestPostMessageTriggersOneResponse(t *testing.T) {
+	ts, _ := newTestNestServer(t)
+	id := newNest(t, ts, "Lab", `"Hugin"`)
+	code, req := post(t, ts.URL+"/api/nests/"+id+"/messages", `{"author":"owner","kind":"request","text":"count the eggs","to":"Hugin"}`)
+	if code != http.StatusCreated {
+		t.Fatalf("request post: %d %v", code, req)
+	}
+	msgs := awaitMessages(t, ts, id, 2)
+	replies := 0
+	for _, m := range msgs {
+		if m["author"] == "Hugin" {
+			replies++
+			if m["kind"] != "say" && m["kind"] != "claim" && m["kind"] != "deliver" {
+				t.Fatalf("crow reply has a bad kind: %v", m["kind"])
+			}
+			if m["refers_to"] != req["msg_id"] {
+				t.Fatalf("crow reply must point at the request, got %v", m["refers_to"])
+			}
+		}
+	}
+	if replies != 1 {
+		t.Fatalf("want exactly one Hugin message, got %d in %v", replies, msgs)
+	}
+}
+
+func TestNoIdleResponse(t *testing.T) {
+	ts, _ := newTestNestServer(t)
+	id := newNest(t, ts, "Lab", `"Hugin"`)
+	code, out := post(t, ts.URL+"/api/nests/"+id+"/messages", `{"author":"owner","text":"just thinking out loud"}`)
+	if code != http.StatusCreated {
+		t.Fatalf("say post: %d %v", code, out)
+	}
+	time.Sleep(300 * time.Millisecond)
+	if got := nestMessages(t, ts, id); len(got) != 1 {
+		t.Fatalf("an unaddressed say must not summon a crow, log: %v", got)
+	}
+}
diff --git a/nestsse_test.go b/nestsse_test.go
new file mode 100644
index 0000000..5197306
--- /dev/null
+++ b/nestsse_test.go
@@ -0,0 +1,53 @@
+package main
+
+import (
+	"bufio"
+	"net/http"
+	"testing"
+	"time"
+)
+
+// TestNestStreamSSE checks GET /api/events?nest_id= streams nest.message events
+// and replays history from Last-Event-ID (the EVENTS.md nest SSE contract).
+func TestNestStreamSSE(t *testing.T) {
+	ts, s := newTestNestServer(t)
+	id := newNest(t, ts, "Lab", `"Hugin"`)
+	s.hub.OpenNest(id)
+	if _, out := post(t, ts.URL+"/api/nests/"+id+"/messages", `{"author":"owner","text":"hello"}`); out["msg_id"] == nil {
+		t.Fatalf("post failed: %v", out)
+	}
+
+	req, err := http.NewRequest("GET", ts.URL+"/api/events?nest_id="+id, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if ct := resp.Header.Get("Content-Type"); ct != "text/event-stream" {
+		t.Fatalf("content type %q", ct)
+	}
+
+	// Read in a goroutine with a deadline so a stuck stream fails, not hangs.
+	got := make(chan bool, 1)
+	go func() {
+		sc := bufio.NewScanner(resp.Body)
+		for sc.Scan() {
+			if sc.Text() == "event: nest.message" {
+				got <- true
+				return
+			}
+		}
+		got <- false
+	}()
+	select {
+	case ok := <-got:
+		if !ok {
+			t.Fatal("stream ended before nest.message appeared")
+		}
+	case <-time.After(2 * time.Second):
+		t.Fatal("no nest.message event within 2s")
+	}
+}