diff --git a/coderd/taskname/taskname.go b/coderd/taskname/taskname.go
index 3351a288cf..c1382c0c62 100644
--- a/coderd/taskname/taskname.go
+++ b/coderd/taskname/taskname.go
@@ -94,26 +94,25 @@ Do not include any additional keys, explanations, or text outside the JSON.`
 var (
 	ErrNoAPIKey        = xerrors.New("no api key provided")
 	ErrNoNameGenerated = xerrors.New("no task name generated")
+
+	markdownCodeFenceRE = regexp.MustCompile("(?s)^```[^\n]*\n(.*?)(?:\n```.*|```\\s*)?$")
 )
 
-// extractJSON strips optional markdown code fences (```json or
-// ```) that LLMs sometimes wrap around JSON output, returning
-// only the inner JSON string. Only well-formed fences with a
-// newline after the opening backticks are stripped; malformed
-// fences are left untouched so that json.Unmarshal fails
-// cleanly and the caller can fall back to other strategies.
+// extractJSON strips optional markdown code fences (```json or ```) that
+// LLMs sometimes wrap around JSON output, returning only the inner JSON
+// string. If the response starts with JSON, it returns the first JSON value so
+// trailing commentary or dangling fences do not break parsing.
 func extractJSON(s string) string {
 	s = strings.TrimSpace(s)
-	if strings.HasPrefix(s, "```") {
-		// Only strip when there is a newline separating the
-		// fence line from the body. Without one we cannot
-		// reliably tell the fence from the content.
-		if idx := strings.Index(s, "\n"); idx != -1 {
-			s = s[idx+1:]
-			s = strings.TrimSuffix(s, "```")
-			s = strings.TrimSpace(s)
-		}
+	if matches := markdownCodeFenceRE.FindStringSubmatch(s); matches != nil {
+		s = strings.TrimSpace(matches[1])
 	}
+
+	var raw json.RawMessage
+	if err := json.NewDecoder(strings.NewReader(s)).Decode(&raw); err == nil {
+		return string(raw)
+	}
+
 	return s
 }
 
diff --git a/coderd/taskname/taskname_internal_test.go b/coderd/taskname/taskname_internal_test.go
index eff0b30de6..b6c977a6be 100644
--- a/coderd/taskname/taskname_internal_test.go
+++ b/coderd/taskname/taskname_internal_test.go
@@ -156,6 +156,21 @@ func TestExtractJSON(t *testing.T) {
 			input:    "```json\n{\n  \"display_name\": \"Fix bug\",\n  \"task_name\": \"fix-bug\"\n}\n```",
 			expected: "{\n  \"display_name\": \"Fix bug\",\n  \"task_name\": \"fix-bug\"\n}",
 		},
+		{
+			name:     "FencedJSONWithTrailingText",
+			input:    "```json\n{\"display_name\": \"Fix bug\", \"task_name\": \"fix-bug\"}\n```\n\nDone.",
+			expected: `{"display_name": "Fix bug", "task_name": "fix-bug"}`,
+		},
+		{
+			name:     "BareJSONWithTrailingFence",
+			input:    "{\"display_name\": \"Fix bug\", \"task_name\": \"fix-bug\"}\n```",
+			expected: `{"display_name": "Fix bug", "task_name": "fix-bug"}`,
+		},
+		{
+			name:     "BareJSONWithTrailingText",
+			input:    "{\"display_name\": \"Fix bug\", \"task_name\": \"fix-bug\"}\n\nDone.",
+			expected: `{"display_name": "Fix bug", "task_name": "fix-bug"}`,
+		},
 		{
 			name:     "FencedNoNewlinePassthrough",
 			input:    "```json{\"display_name\": \"Fix bug\", \"task_name\": \"fix-bug\"}```",
@@ -235,6 +250,18 @@ func TestGenerateFromAnthropicMock(t *testing.T) {
 			expectedDisplayName: "Setup CI",
 			expectedNamePrefix:  "setup-ci-",
 		},
+		{
+			name:                "FencedJSONWithTrailingText",
+			responseText:        "```json\n{\"display_name\": \"Debug auth\", \"task_name\": \"debug-auth\"}\n```\n\nDone.",
+			expectedDisplayName: "Debug auth",
+			expectedNamePrefix:  "debug-auth-",
+		},
+		{
+			name:                "BareJSONWithTrailingFence",
+			responseText:        "{\"display_name\": \"Setup CI\", \"task_name\": \"setup-ci\"}\n```",
+			expectedDisplayName: "Setup CI",
+			expectedNamePrefix:  "setup-ci-",
+		},
 	}
 
 	for _, tc := range tests {