diff --git a/changelog/unreleased/workbuddy-401-refresh-false-auth.md b/changelog/unreleased/workbuddy-401-refresh-false-auth.md
new file mode 100644
index 00000000..992db28b
--- /dev/null
+++ b/changelog/unreleased/workbuddy-401-refresh-false-auth.md
@@ -0,0 +1,7 @@
+### English
+
+- WorkBuddy chat no longer treats every post-401 token refresh failure as `login_required`: only real session-dead / auth refresh failures keep that path; transport and 5xx refresh errors stay `unavailable` with a short pool cooldown and a diagnostic Observe entry.
+
+### 中文
+
+- WorkBuddy 聊天在 401 后刷新 token 失败时不再一律标成 `login_required`：仅真实 session-dead / auth 刷新失败保留该路径；运输错误与 5xx 刷新失败保持 `unavailable`，走池短冷却，并用现有 Observe 记下可诊断原因。
diff --git a/internal/providers/workbuddy/client.go b/internal/providers/workbuddy/client.go
index 03f8e7c9..617f1ef4 100644
--- a/internal/providers/workbuddy/client.go
+++ b/internal/providers/workbuddy/client.go
@@ -522,11 +522,13 @@ func (c *Client) ChatStream(ctx context.Context, accountID string, req translate
 
 // sendChat performs one chat round trip and returns a 2xx response with an
 // unread body. A 401 usually means the access token expired before its JWT
-// clock said so: refresh the token once and retry on the same account. Only
-// when the refresh itself fails is the 401 surfaced as KindAuth, which lets
-// the executor fail over to another account (Refresh already marks a dead
-// session as login_required). TLS certificate verification failures are
-// deterministic configuration errors and are reported without retry.
+// clock said so: refresh the token once and retry on the same account. When
+// refresh itself fails, only a real KindAuth / session-dead failure is
+// surfaced as KindAuth (Refresh already Observe(login_required) there);
+// transport / 5xx / other non-auth refresh failures return KindUnavailable
+// so the pool applies short cooldown + failover without marking the account
+// login_required. TLS certificate verification failures are deterministic
+// configuration errors and are reported without retry.
 func (c *Client) sendChat(ctx context.Context, accountID string, credential Credential, req translate.ChatRequest, httpReq *http.Request) (*http.Response, error) {
 	client, err := c.httpClient(ctx, accountID)
 	if err != nil {
@@ -553,11 +555,22 @@ func (c *Client) sendChat(ctx context.Context, accountID string, credential Cred
 			if tlsErr := tlsVerifyError(refreshErr); tlsErr != nil {
 				return nil, tlsErr
 			}
-			out := classifiedError(resp.StatusCode, body)
-			if pe, ok := out.(*providers.Error); ok && pe.Kind == accounts.KindAuth {
-				pe.Message = "token refresh after 401 failed; re-login required"
+			if refreshFailureIsAuth(refreshErr) {
+				out := classifiedError(resp.StatusCode, body)
+				if pe, ok := out.(*providers.Error); ok && pe.Kind == accounts.KindAuth {
+					pe.Message = "token refresh after 401 failed; re-login required"
+				}
+				return nil, out
+			}
+			// Non-auth refresh failure (transport / 5xx / etc.): keep the
+			// account out of login_required; pool short-cools via Unavailable.
+			summary := refreshErr.Error()
+			_ = c.store.Observe(ctx, accountID, credential.UID, "error", "token refresh after 401: "+summary, accounts.KindUnavailable)
+			return nil, &providers.Error{
+				Kind:    accounts.KindUnavailable,
+				Status:  http.StatusBadGateway,
+				Message: "token refresh after 401 unavailable: " + summary,
 			}
-			return nil, out
 		}
 		credential = fresh
 		httpReq, _, err = c.chatRequest(ctx, accountID, credential, req)
@@ -572,6 +585,26 @@ func (c *Client) sendChat(ctx context.Context, accountID string, credential Cred
 // account or transient network fault.
 const tlsVerifyHint = "TLS certificate verification failed: the upstream certificate chain is not trusted by this host (corporate proxy / HTTPS-decrypting VPN?). Install the issuing root CA into the system trust store or set SSL_CERT_FILE, then retry."
 
+// refreshFailureIsAuth reports whether a Refresh error is a real session-dead
+// / KindAuth failure. Reuses Classify and the existing session-dead markers;
+// Refresh already Observe(login_required) on that path. Non-auth failures
+// (transport, 5xx, envelope) must not be upgraded to KindAuth in sendChat.
+func refreshFailureIsAuth(err error) bool {
+	if err == nil {
+		return false
+	}
+	var pe *providers.Error
+	if errors.As(err, &pe) && pe.Kind == accounts.KindAuth {
+		return true
+	}
+	msg := err.Error()
+	// Refresh returns "workbuddy session dead: re-login required" for Classify KindAuth.
+	if strings.Contains(strings.ToLower(msg), "session dead") {
+		return true
+	}
+	return Classify(0, msg).Kind == accounts.KindAuth
+}
+
 func tlsVerifyError(err error) error {
 	if !providers.IsTLSVerifyError(err) {
 		return nil
diff --git a/internal/providers/workbuddy/upstream_align_test.go b/internal/providers/workbuddy/upstream_align_test.go
index 3b232a1d..9a6122ee 100644
--- a/internal/providers/workbuddy/upstream_align_test.go
+++ b/internal/providers/workbuddy/upstream_align_test.go
@@ -7,6 +7,7 @@ import (
 	"errors"
 	"net/http"
 	"net/http/httptest"
+	"strings"
 	"sync/atomic"
 	"testing"
 
@@ -70,7 +71,7 @@ func TestChat401RefreshesOnceAndRetriesSameAccount(t *testing.T) {
 
 func TestChat401RefreshFailureSurfacesAuthForFailover(t *testing.T) {
 	var chats, refreshes int32
-	client, _ := newAlignClient(t, Credential{AccessToken: "old", RefreshToken: "rt", UID: "u1", Domain: DomainCN, ExpiresAt: 4102444800},
+	client, store := newAlignClient(t, Credential{AccessToken: "old", RefreshToken: "rt", UID: "u1", Domain: DomainCN, ExpiresAt: 4102444800},
 		func(w http.ResponseWriter, r *http.Request) {
 			switch r.URL.Path {
 			case pathProductConfig:
@@ -88,9 +89,86 @@ func TestChat401RefreshFailureSurfacesAuthForFailover(t *testing.T) {
 	if !errors.As(err, &pe) || pe.Kind != accounts.KindAuth {
 		t.Fatalf("want KindAuth after failed refresh, got %v", err)
 	}
+	if pe.Message != "token refresh after 401 failed; re-login required" {
+		t.Fatalf("auth message = %q", pe.Message)
+	}
+	if chats != 1 || refreshes != 1 {
+		t.Fatalf("chats=%d refreshes=%d; refresh must run once and not retry chat", chats, refreshes)
+	}
+	// Refresh Observe(login_required); sendChat must not Observe unavailable.
+	if store.lastStatus != "login_required" || store.lastKind != accounts.KindAuth {
+		t.Fatalf("want Refresh Observe(login_required/auth), got status=%q kind=%q", store.lastStatus, store.lastKind)
+	}
+}
+
+func TestChat401RefreshNonAuthSurfacesUnavailable(t *testing.T) {
+	var chats, refreshes int32
+	client, store := newAlignClient(t, Credential{AccessToken: "old", RefreshToken: "rt", UID: "u1", Domain: DomainCN, ExpiresAt: 4102444800},
+		func(w http.ResponseWriter, r *http.Request) {
+			switch r.URL.Path {
+			case pathProductConfig:
+				catalogOK(w)
+			case pathTokenRefresh:
+				atomic.AddInt32(&refreshes, 1)
+				w.WriteHeader(http.StatusBadGateway)
+				_, _ = w.Write([]byte(`upstream boom`))
+			case pathChat:
+				atomic.AddInt32(&chats, 1)
+				w.WriteHeader(http.StatusUnauthorized)
+			}
+		})
+	_, _, err := client.ChatStream(context.Background(), "acc1", alignReq)
+	var pe *providers.Error
+	if !errors.As(err, &pe) || pe.Kind != accounts.KindUnavailable {
+		t.Fatalf("want KindUnavailable after non-auth refresh failure, got %v", err)
+	}
+	if strings.Contains(pe.Message, "re-login required") {
+		t.Fatalf("non-auth refresh must not surface re-login message: %q", pe.Message)
+	}
+	if !strings.Contains(pe.Message, "refresh") {
+		t.Fatalf("want refresh failure summary in message, got %q", pe.Message)
+	}
 	if chats != 1 || refreshes != 1 {
 		t.Fatalf("chats=%d refreshes=%d; refresh must run once and not retry chat", chats, refreshes)
 	}
+	if store.lastKind == accounts.KindAuth || store.lastStatus == "login_required" {
+		t.Fatalf("non-auth refresh must not Observe login_required/auth: status=%q kind=%q", store.lastStatus, store.lastKind)
+	}
+	if store.lastKind != accounts.KindUnavailable || store.lastStatus != "error" {
+		t.Fatalf("want Observe(error/unavailable) diagnostic, got status=%q kind=%q", store.lastStatus, store.lastKind)
+	}
+}
+
+func TestChat401RefreshSessionDeadBodySurfacesAuth(t *testing.T) {
+	var chats, refreshes int32
+	client, store := newAlignClient(t, Credential{AccessToken: "old", RefreshToken: "rt", UID: "u1", Domain: DomainCN, ExpiresAt: 4102444800},
+		func(w http.ResponseWriter, r *http.Request) {
+			switch r.URL.Path {
+			case pathProductConfig:
+				catalogOK(w)
+			case pathTokenRefresh:
+				atomic.AddInt32(&refreshes, 1)
+				w.WriteHeader(http.StatusOK)
+				_ = json.NewEncoder(w).Encode(map[string]any{
+					"code": sessionDeadCode,
+					"msg":  sessionDeadText,
+				})
+			case pathChat:
+				atomic.AddInt32(&chats, 1)
+				w.WriteHeader(http.StatusUnauthorized)
+			}
+		})
+	_, _, err := client.ChatStream(context.Background(), "acc1", alignReq)
+	var pe *providers.Error
+	if !errors.As(err, &pe) || pe.Kind != accounts.KindAuth {
+		t.Fatalf("want KindAuth for session-dead refresh body, got %v", err)
+	}
+	if store.lastStatus != "login_required" || store.lastKind != accounts.KindAuth {
+		t.Fatalf("want Refresh Observe(login_required/auth), got status=%q kind=%q", store.lastStatus, store.lastKind)
+	}
+	if chats != 1 || refreshes != 1 {
+		t.Fatalf("chats=%d refreshes=%d", chats, refreshes)
+	}
 }
 
 func TestTLSVerifyErrorIsWrappedNotRetried(t *testing.T) {