diff --git a/clients/clients.go b/clients/clients.go
index 50a589c..7856a62 100644
--- a/clients/clients.go
+++ b/clients/clients.go
@@ -124,7 +124,7 @@ resp, err := h.client.Do(req)
 if err != nil {
 return nil, fmt.Errorf("http %s %s: %w", req.Method, req.URL.Path, err)
 }
-defer resp.Body.Close()
+defer func() { _ = resp.Body.Close() }()
 
 buf := getBuf()
 defer putBuf(buf)
@@ -420,7 +420,6 @@ type MilvusClient struct {
 Host       string
 Port       int
 Collection string
-connected  bool
 }
 
 // NewMilvusClient creates a Milvus client.
diff --git a/clients/clients_test.go b/clients/clients_test.go
index bb87404..0406552 100644
--- a/clients/clients_test.go
+++ b/clients/clients_test.go
@@ -90,14 +90,14 @@ func TestEmbeddingsClient_Embed(t *testing.T) {
 			t.Errorf("method = %s, want POST", r.Method)
 		}
 		var req map[string]any
-		json.NewDecoder(r.Body).Decode(&req)
+		_ = json.NewDecoder(r.Body).Decode(&req)
 		input, _ := req["input"].([]any)
 		if len(input) != 2 {
 			t.Errorf("input len = %d, want 2", len(input))
 		}
 
 		w.Header().Set("Content-Type", "application/json")
-		json.NewEncoder(w).Encode(map[string]any{
+		_ = json.NewEncoder(w).Encode(map[string]any{
 			"data": []map[string]any{
 				{"embedding": []float64{0.1, 0.2, 0.3}},
 				{"embedding": []float64{0.4, 0.5, 0.6}},
@@ -121,7 +121,7 @@ func TestEmbeddingsClient_Embed(t *testing.T) {
 
 func TestEmbeddingsClient_EmbedSingle(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		json.NewEncoder(w).Encode(map[string]any{
+		_ = json.NewEncoder(w).Encode(map[string]any{
 			"data": []map[string]any{
 				{"embedding": []float64{1.0, 2.0}},
 			},
@@ -141,7 +141,7 @@ func TestEmbeddingsClient_EmbedSingle(t *testing.T) {
 
 func TestEmbeddingsClient_EmbedEmpty(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		json.NewEncoder(w).Encode(map[string]any{"data": []any{}})
+		_ = json.NewEncoder(w).Encode(map[string]any{"data": []any{}})
 	}))
 	defer ts.Close()
 
@@ -175,11 +175,11 @@ func TestEmbeddingsClient_Health(t *testing.T) {
 func TestRerankerClient_Rerank(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		var req map[string]any
-		json.NewDecoder(r.Body).Decode(&req)
+		_ = json.NewDecoder(r.Body).Decode(&req)
 		if req["query"] != "test query" {
 			t.Errorf("query = %v", req["query"])
 		}
-		json.NewEncoder(w).Encode(map[string]any{
+		_ = json.NewEncoder(w).Encode(map[string]any{
 			"results": []map[string]any{
 				{"index": 1, "relevance_score": 0.95},
 				{"index": 0, "relevance_score": 0.80},
@@ -207,7 +207,7 @@ func TestRerankerClient_Rerank(t *testing.T) {
 
 func TestRerankerClient_RerankFallbackScore(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		json.NewEncoder(w).Encode(map[string]any{
+		_ = json.NewEncoder(w).Encode(map[string]any{
 			"results": []map[string]any{
 				{"index": 0, "score": 0.77, "relevance_score": 0}, // some APIs only set score
 			},
@@ -235,13 +235,13 @@ func TestLLMClient_Generate(t *testing.T) {
 			t.Errorf("path = %q", r.URL.Path)
 		}
 		var req map[string]any
-		json.NewDecoder(r.Body).Decode(&req)
+		_ = json.NewDecoder(r.Body).Decode(&req)
 		msgs, _ := req["messages"].([]any)
 		if len(msgs) == 0 {
 			t.Error("no messages in request")
 		}
 
-		json.NewEncoder(w).Encode(map[string]any{
+		_ = json.NewEncoder(w).Encode(map[string]any{
 			"choices": []map[string]any{
 				{"message": map[string]any{"content": "Paris is the capital of France."}},
 			},
@@ -262,13 +262,13 @@ func TestLLMClient_Generate(t *testing.T) {
 func TestLLMClient_GenerateWithContext(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		var req map[string]any
-		json.NewDecoder(r.Body).Decode(&req)
+		_ = json.NewDecoder(r.Body).Decode(&req)
 		msgs, _ := req["messages"].([]any)
 		// Should have system + user message
 		if len(msgs) != 2 {
 			t.Errorf("expected 2 messages, got %d", len(msgs))
 		}
-		json.NewEncoder(w).Encode(map[string]any{
+		_ = json.NewEncoder(w).Encode(map[string]any{
 			"choices": []map[string]any{
 				{"message": map[string]any{"content": "answer with context"}},
 			},
@@ -288,7 +288,7 @@ func TestLLMClient_GenerateWithContext(t *testing.T) {
 
 func TestLLMClient_GenerateNoChoices(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		json.NewEncoder(w).Encode(map[string]any{"choices": []any{}})
+		_ = json.NewEncoder(w).Encode(map[string]any{"choices": []any{}})
 	}))
 	defer ts.Close()
 
@@ -312,7 +312,7 @@ func TestTTSClient_Synthesize(t *testing.T) {
 		if r.URL.Query().Get("text") != "hello world" {
 			t.Errorf("text = %q", r.URL.Query().Get("text"))
 		}
-		w.Write(expected)
+		_, _ = w.Write(expected)
 	}))
 	defer ts.Close()
 
@@ -331,7 +331,7 @@ func TestTTSClient_SynthesizeWithSpeaker(t *testing.T) {
 		if r.URL.Query().Get("speaker_id") != "alice" {
 			t.Errorf("speaker_id = %q", r.URL.Query().Get("speaker_id"))
 		}
-		w.Write([]byte{0x01})
+		_, _ = w.Write([]byte{0x01})
 	}))
 	defer ts.Close()
 
@@ -365,7 +365,7 @@ func TestSTTClient_Transcribe(t *testing.T) {
 			t.Errorf("file size = %d, want 100", len(data))
 		}
 
-		json.NewEncoder(w).Encode(map[string]string{"text": "hello world"})
+		_ = json.NewEncoder(w).Encode(map[string]string{"text": "hello world"})
 	}))
 	defer ts.Close()
 
@@ -384,7 +384,7 @@ func TestSTTClient_TranscribeTranslate(t *testing.T) {
 		if r.URL.Path != "/v1/audio/translations" {
 			t.Errorf("path = %q, want /v1/audio/translations", r.URL.Path)
 		}
-		json.NewEncoder(w).Encode(map[string]string{"text": "translated"})
+		_ = json.NewEncoder(w).Encode(map[string]string{"text": "translated"})
 	}))
 	defer ts.Close()
 
@@ -406,7 +406,7 @@ func TestSTTClient_TranscribeTranslate(t *testing.T) {
 func TestHTTPError4xx(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(422)
-		w.Write([]byte(`{"error": "bad input"}`))
+		_, _ = w.Write([]byte(`{"error": "bad input"}`))
 	}))
 	defer ts.Close()
 
@@ -423,7 +423,7 @@ func TestHTTPError4xx(t *testing.T) {
 func TestHTTPError5xx(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(500)
-		w.Write([]byte("internal server error"))
+		_, _ = w.Write([]byte("internal server error"))
 	}))
 	defer ts.Close()
 
@@ -467,8 +467,8 @@ func TestBuildMessages(t *testing.T) {
 
 func BenchmarkPostJSON(b *testing.B) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		io.Copy(io.Discard, r.Body)
-		w.Write([]byte(`{"ok":true}`))
+		_, _ = io.Copy(io.Discard, r.Body)
+		_, _ = w.Write([]byte(`{"ok":true}`))
 	}))
 	defer ts.Close()
 
@@ -482,7 +482,7 @@ func BenchmarkPostJSON(b *testing.B) {
 
 	b.ResetTimer()
 	for b.Loop() {
-		c.postJSON(ctx, "/test", payload)
+		_, _ = c.postJSON(ctx, "/test", payload)
 	}
 }
 
diff --git a/handler/handler_test.go b/handler/handler_test.go
index 84a1eb0..9df5f4a 100644
--- a/handler/handler_test.go
+++ b/handler/handler_test.go
@@ -66,8 +66,8 @@ func TestCallbackRegistration(t *testing.T) {
 	}
 
 	// Verify setup/teardown work when called directly.
-	h.onSetup(context.Background())
-	h.onTeardown(context.Background())
+	_ = h.onSetup(context.Background())
+	_ = h.onTeardown(context.Background())
 	if !setupCalled || !teardownCalled {
 		t.Error("callbacks should have been invoked")
 	}
@@ -290,7 +290,7 @@ func BenchmarkWrapTypedHandler(b *testing.B) {
 	h := New("ai.test", cfg)
 	h.OnTypedMessage(func(ctx context.Context, msg *nats.Msg) (any, error) {
 		var req benchReq
-		msgpack.Unmarshal(msg.Data, &req)
+		_ = msgpack.Unmarshal(msg.Data, &req)
 		return map[string]any{"ok": true}, nil
 	})
 
diff --git a/health/health.go b/health/health.go
index d2e5284..e3ff3ea 100644
--- a/health/health.go
+++ b/health/health.go
@@ -8,7 +8,6 @@ import (
 	"log/slog"
 	"net"
 	"net/http"
-	"sync/atomic"
 	"time"
 )
 
@@ -22,7 +21,6 @@ type Server struct {
 	readyPath  string
 	readyCheck ReadyFunc
 	srv        *http.Server
-	ready      atomic.Bool
 }
 
 // New creates a health server on the given port.
diff --git a/health/health_test.go b/health/health_test.go
index 2d4f963..2c00497 100644
--- a/health/health_test.go
+++ b/health/health_test.go
@@ -19,7 +19,7 @@ func TestHealthEndpoint(t *testing.T) {
 	if err != nil {
 		t.Fatalf("health request failed: %v", err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 
 	if resp.StatusCode != 200 {
 		t.Errorf("expected 200, got %d", resp.StatusCode)
@@ -42,7 +42,7 @@ func TestReadyEndpointDefault(t *testing.T) {
 	if err != nil {
 		t.Fatalf("ready request failed: %v", err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 
 	if resp.StatusCode != 200 {
 		t.Errorf("expected 200, got %d", resp.StatusCode)
@@ -60,7 +60,7 @@ func TestReadyEndpointNotReady(t *testing.T) {
 	if err != nil {
 		t.Fatalf("ready request failed: %v", err)
 	}
-	resp.Body.Close()
+	_ = resp.Body.Close()
 	if resp.StatusCode != 503 {
 		t.Errorf("expected 503 when not ready, got %d", resp.StatusCode)
 	}
@@ -70,7 +70,7 @@ func TestReadyEndpointNotReady(t *testing.T) {
 	if err != nil {
 		t.Fatalf("ready request failed: %v", err)
 	}
-	resp2.Body.Close()
+	_ = resp2.Body.Close()
 	if resp2.StatusCode != 200 {
 		t.Errorf("expected 200 when ready, got %d", resp2.StatusCode)
 	}
diff --git a/messages/bench_test.go b/messages/bench_test.go
index 7310641..ee107dd 100644
--- a/messages/bench_test.go
+++ b/messages/bench_test.go
@@ -178,7 +178,7 @@ func BenchmarkEncode_ChatRequest_MsgpackMap(b *testing.B) {
 	data := chatRequestMap()
 	b.ResetTimer()
 	for b.Loop() {
-		msgpack.Marshal(data)
+		_, _ = msgpack.Marshal(data)
 	}
 }
 
@@ -186,7 +186,7 @@ func BenchmarkEncode_ChatRequest_MsgpackStruct(b *testing.B) {
 	data := chatRequestStruct()
 	b.ResetTimer()
 	for b.Loop() {
-		msgpack.Marshal(data)
+		_, _ = msgpack.Marshal(data)
 	}
 }
 
@@ -194,7 +194,7 @@ func BenchmarkEncode_ChatRequest_Protobuf(b *testing.B) {
 	data := chatRequestProto()
 	b.ResetTimer()
 	for b.Loop() {
-		proto.Marshal(data)
+		_, _ = proto.Marshal(data)
 	}
 }
 
@@ -202,7 +202,7 @@ func BenchmarkEncode_VoiceResponse_MsgpackMap(b *testing.B) {
 	data := voiceResponseMap()
 	b.ResetTimer()
 	for b.Loop() {
-		msgpack.Marshal(data)
+		_, _ = msgpack.Marshal(data)
 	}
 }
 
@@ -210,7 +210,7 @@ func BenchmarkEncode_VoiceResponse_MsgpackStruct(b *testing.B) {
 	data := voiceResponseStruct()
 	b.ResetTimer()
 	for b.Loop() {
-		msgpack.Marshal(data)
+		_, _ = msgpack.Marshal(data)
 	}
 }
 
@@ -218,7 +218,7 @@ func BenchmarkEncode_VoiceResponse_Protobuf(b *testing.B) {
 	data := voiceResponseProto()
 	b.ResetTimer()
 	for b.Loop() {
-		proto.Marshal(data)
+		_, _ = proto.Marshal(data)
 	}
 }
 
@@ -226,7 +226,7 @@ func BenchmarkEncode_TTSChunk_MsgpackMap(b *testing.B) {
 	data := ttsChunkMap()
 	b.ResetTimer()
 	for b.Loop() {
-		msgpack.Marshal(data)
+		_, _ = msgpack.Marshal(data)
 	}
 }
 
@@ -234,7 +234,7 @@ func BenchmarkEncode_TTSChunk_MsgpackStruct(b *testing.B) {
 	data := ttsChunkStruct()
 	b.ResetTimer()
 	for b.Loop() {
-		msgpack.Marshal(data)
+		_, _ = msgpack.Marshal(data)
 	}
 }
 
@@ -242,7 +242,7 @@ func BenchmarkEncode_TTSChunk_Protobuf(b *testing.B) {
 	data := ttsChunkProto()
 	b.ResetTimer()
 	for b.Loop() {
-		proto.Marshal(data)
+		_, _ = proto.Marshal(data)
 	}
 }
 
@@ -255,7 +255,7 @@ func BenchmarkDecode_ChatRequest_MsgpackMap(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m map[string]any
-		msgpack.Unmarshal(encoded, &m)
+		_ = msgpack.Unmarshal(encoded, &m)
 	}
 }
 
@@ -264,7 +264,7 @@ func BenchmarkDecode_ChatRequest_MsgpackStruct(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m ChatRequest
-		msgpack.Unmarshal(encoded, &m)
+		_ = msgpack.Unmarshal(encoded, &m)
 	}
 }
 
@@ -273,7 +273,7 @@ func BenchmarkDecode_ChatRequest_Protobuf(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m pb.ChatRequest
-		proto.Unmarshal(encoded, &m)
+		_ = proto.Unmarshal(encoded, &m)
 	}
 }
 
@@ -282,7 +282,7 @@ func BenchmarkDecode_VoiceResponse_MsgpackMap(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m map[string]any
-		msgpack.Unmarshal(encoded, &m)
+		_ = msgpack.Unmarshal(encoded, &m)
 	}
 }
 
@@ -291,7 +291,7 @@ func BenchmarkDecode_VoiceResponse_MsgpackStruct(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m VoiceResponse
-		msgpack.Unmarshal(encoded, &m)
+		_ = msgpack.Unmarshal(encoded, &m)
 	}
 }
 
@@ -300,7 +300,7 @@ func BenchmarkDecode_VoiceResponse_Protobuf(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m pb.VoiceResponse
-		proto.Unmarshal(encoded, &m)
+		_ = proto.Unmarshal(encoded, &m)
 	}
 }
 
@@ -309,7 +309,7 @@ func BenchmarkDecode_TTSChunk_MsgpackMap(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m map[string]any
-		msgpack.Unmarshal(encoded, &m)
+		_ = msgpack.Unmarshal(encoded, &m)
 	}
 }
 
@@ -318,7 +318,7 @@ func BenchmarkDecode_TTSChunk_MsgpackStruct(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m TTSAudioChunk
-		msgpack.Unmarshal(encoded, &m)
+		_ = msgpack.Unmarshal(encoded, &m)
 	}
 }
 
@@ -327,7 +327,7 @@ func BenchmarkDecode_TTSChunk_Protobuf(b *testing.B) {
 	b.ResetTimer()
 	for b.Loop() {
 		var m pb.TTSAudioChunk
-		proto.Unmarshal(encoded, &m)
+		_ = proto.Unmarshal(encoded, &m)
 	}
 }
 
@@ -341,7 +341,7 @@ func BenchmarkRoundtrip_ChatRequest_MsgpackMap(b *testing.B) {
 	for b.Loop() {
 		enc, _ := msgpack.Marshal(data)
 		var dec map[string]any
-		msgpack.Unmarshal(enc, &dec)
+		_ = msgpack.Unmarshal(enc, &dec)
 	}
 }
 
@@ -351,7 +351,7 @@ func BenchmarkRoundtrip_ChatRequest_MsgpackStruct(b *testing.B) {
 	for b.Loop() {
 		enc, _ := msgpack.Marshal(data)
 		var dec ChatRequest
-		msgpack.Unmarshal(enc, &dec)
+		_ = msgpack.Unmarshal(enc, &dec)
 	}
 }
 
@@ -361,7 +361,7 @@ func BenchmarkRoundtrip_ChatRequest_Protobuf(b *testing.B) {
 	for b.Loop() {
 		enc, _ := proto.Marshal(data)
 		var dec pb.ChatRequest
-		proto.Unmarshal(enc, &dec)
+		_ = proto.Unmarshal(enc, &dec)
 	}
 }
 
diff --git a/natsutil/natsutil_test.go b/natsutil/natsutil_test.go
index afb663f..6898a52 100644
--- a/natsutil/natsutil_test.go
+++ b/natsutil/natsutil_test.go
@@ -200,7 +200,7 @@ func BenchmarkEncodeMap(b *testing.B) {
 		"top_k":      10,
 	}
 	for b.Loop() {
-		msgpack.Marshal(data)
+		_, _ = msgpack.Marshal(data)
 	}
 }
 
@@ -212,7 +212,7 @@ func BenchmarkEncodeStruct(b *testing.B) {
 		Active:    true,
 	}
 	for b.Loop() {
-		msgpack.Marshal(data)
+		_, _ = msgpack.Marshal(data)
 	}
 }
 
@@ -226,7 +226,7 @@ func BenchmarkDecodeMap(b *testing.B) {
 	})
 	for b.Loop() {
 		var m map[string]any
-		msgpack.Unmarshal(raw, &m)
+		_ = msgpack.Unmarshal(raw, &m)
 	}
 }
 
@@ -239,7 +239,7 @@ func BenchmarkDecodeStruct(b *testing.B) {
 	})
 	for b.Loop() {
 		var m testMessage
-		msgpack.Unmarshal(raw, &m)
+		_ = msgpack.Unmarshal(raw, &m)
 	}
 }
 
@@ -251,6 +251,6 @@ func BenchmarkDecodeAudio32KB(b *testing.B) {
 	})
 	for b.Loop() {
 		var m audioMessage
-		msgpack.Unmarshal(raw, &m)
+		_ = msgpack.Unmarshal(raw, &m)
 	}
 }