fix: apply shared conversation protection to scalar logs and named controls

internal/logging/redact.go

@@ -185,6 +185,9 @@ func redactErrorJSON(s string) string {
 
 func cleanString(s string) string {
 	s = privatePEMInText.ReplaceAllString(s, redacted)
+	// Scalar messages/errors and HTTP text share the same labelled-content
+	// protection, rather than protecting conversational blocks only in bodies.
+	s = redactConversationLines(redactMarkup(s))
 	s = redactErrorJSON(s)
 	s = authHeaderInText.ReplaceAllStringFunc(s, func(header string) string {
 		index := strings.IndexAny(header, ":=")

internal/logging/text.go

@@ -58,7 +58,10 @@ func redactMarkup(body string) string {
 				}
 			}
 			out.WriteString(tag)
-			if kind == html.StartTagToken && sensitive(token.Data) {
+			// A named sensitive field owns both its value attribute and enclosed
+			// content (textarea/select/custom controls). Void inputs own only value;
+			// they must never swallow following non-sensitive business elements.
+			if kind == html.StartTagToken && (sensitive(token.Data) || (hideValue && !voidMarkupElement(token.Data))) {
 				out.WriteString(redacted)
 				hiddenTag = token.Data
 				depth = 1
@@ -70,6 +73,15 @@ func redactMarkup(body string) string {
 	return out.String()
 }
 
+func voidMarkupElement(name string) bool {
+	switch name {
+	case "area", "base", "br", "col", "embed", "hr", "img", "input", "link", "meta", "param", "source", "track", "wbr":
+		return true
+	default:
+		return false
+	}
+}
+
 // A form can be identified without guessing semantic values. Untouched pairs
 // preserve their original encoding and order, including duplicate field names.
 func redactForm(body string) (string, bool) {
@@ -104,6 +116,16 @@ func redactForm(body string) (string, bool) {
 
 var textFieldLine = regexp.MustCompile(`^\s*([A-Za-z_][A-Za-z0-9_.-]*)\s*[:=]`)
 
+func conversationField(key string) bool {
+	key = strings.ToLower(strings.NewReplacer("_", "", "-", "", ".", "").Replace(key))
+	switch key {
+	case "prompt", "systemprompt", "systemmessage", "instructions", "messages", "transcript", "transcription", "text", "content", "audio", "closingremark", "conversation":
+		return true
+	default:
+		return false
+	}
+}
+
 func redactConversationLines(body string) string {
 	lines := strings.SplitAfter(body, "\n")
 	hiding := false
@@ -129,7 +151,9 @@ func redactConversationLines(body string) string {
 			if strings.HasSuffix(line, "\n") {
 				lines[i] += "\n"
 			}
-			hiding = true
+			// Credentials/header fields own their single line, not unrelated
+			// following diagnostics. Only conversational fields own continuation.
+			hiding = conversationField(field[1])
 		}
 	}
 	return strings.Join(lines, "")

internal/logging/text_security_test.go

@@ -11,6 +11,44 @@ import (
 	"testing"
 )
 
+func TestAssociatedSensitiveControlsHideContentWithoutSwallowingBusiness(t *testing.T) {
+	body := `<form><input name="password" value="private-password"><p>business-before</p><textarea name="prompt">private-full-prompt</textarea><select name="messages"><option>private-full-dialogue</option></select><div name="transcript">private-transcript</div><p>business-after</p></form>`
+	safe, err := RedactText([]byte(body))
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, secret := range []string{"private-password", "private-full-prompt", "private-full-dialogue", "private-transcript"} {
+		if strings.Contains(safe, secret) {
+			t.Fatalf("leak %s: %s", secret, safe)
+		}
+	}
+	for _, keep := range []string{"business-before", "business-after"} {
+		if !strings.Contains(safe, keep) {
+			t.Fatal("non-sensitive markup lost", safe)
+		}
+	}
+}
+
+func TestFreeTextConversationIsHiddenInBothModesAndAllScalarPaths(t *testing.T) {
+	value := "upstream failed\nmessages:\nuser: private-user-turn\nassistant: private-assistant-turn\n\nstatus=retry_pending\nattempts=2"
+	for _, debug := range []bool{false, true} {
+		out := installTestLogger(t, debug)
+		slog.Error("operation failed", "error", errors.New(value), "detail", value)
+		slog.Info(value, "stage", "failure_observed")
+		text := out.String()
+		for _, secret := range []string{"private-user-turn", "private-assistant-turn"} {
+			if strings.Contains(text, secret) {
+				t.Fatalf("leak in mode %v: %s", debug, text)
+			}
+		}
+		for _, keep := range []string{"upstream failed", "retry_pending", "attempts=2"} {
+			if !strings.Contains(text, keep) {
+				t.Fatal("failure metadata lost", text)
+			}
+		}
+	}
+}
+
 func TestFreeTextAuthorizationAndUnlabelledPrivatePEMAreHidden(t *testing.T) {
 	for _, debug := range []bool{false, true} {
 		out := installTestLogger(t, debug)