diff --git a/src/cdp/cdp.zig b/src/cdp/cdp.zig
index 3fcf14dc..d8878bdc 100644
--- a/src/cdp/cdp.zig
+++ b/src/cdp/cdp.zig
@@ -151,18 +151,18 @@ pub fn CDPT(comptime TypeProvider: type) type {
                 if (std.mem.eql(u8, input_session_id, "STARTUP")) {
                     is_startup = true;
                 } else if (self.isValidSessionId(input_session_id) == false) {
-                    return command.sendError(-32001, "Unknown sessionId");
+                    return command.sendError(-32001, "Unknown sessionId", .{});
                 }
             }
 
             if (is_startup) {
                 dispatchStartupCommand(&command) catch |err| {
-                    command.sendError(-31999, @errorName(err)) catch {};
+                    command.sendError(-31999, @errorName(err), .{}) catch {};
                     return err;
                 };
             } else {
                 dispatchCommand(&command, input.method) catch |err| {
-                    command.sendError(-31998, @errorName(err)) catch {};
+                    command.sendError(-31998, @errorName(err), .{}) catch {};
                     return err;
                 };
             }
@@ -757,10 +757,14 @@ pub fn Command(comptime CDP_T: type, comptime Sender: type) type {
             return self.cdp.sendEvent(method, p, opts);
         }
 
-        pub fn sendError(self: *Self, code: i32, message: []const u8) !void {
+        const SendErrorOpts = struct {
+            include_session_id: bool = true,
+        };
+        pub fn sendError(self: *Self, code: i32, message: []const u8, opts: SendErrorOpts) !void {
             return self.sender.sendJSON(.{
                 .id = self.input.id,
                 .@"error" = .{ .code = code, .message = message },
+                .sessionId = if (opts.include_session_id) self.input.session_id else null,
             });
         }
 
diff --git a/src/cdp/domains/dom.zig b/src/cdp/domains/dom.zig
index 3a517ee4..c482d90d 100644
--- a/src/cdp/domains/dom.zig
+++ b/src/cdp/domains/dom.zig
@@ -471,7 +471,7 @@ fn getFrameOwner(cmd: anytype) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const target_id = bc.target_id orelse return error.TargetNotLoaded;
     if (std.mem.eql(u8, target_id, params.frameId) == false) {
-        return cmd.sendError(-32000, "Frame with the given id does not belong to the target.");
+        return cmd.sendError(-32000, "Frame with the given id does not belong to the target.", .{});
     }
 
     const page = bc.session.currentPage() orelse return error.PageNotLoaded;
diff --git a/src/cdp/domains/target.zig b/src/cdp/domains/target.zig
index 87fe4324..0f55bb74 100644
--- a/src/cdp/domains/target.zig
+++ b/src/cdp/domains/target.zig
@@ -79,7 +79,7 @@ fn createBrowserContext(cmd: anytype) !void {
     }
 
     const bc = cmd.createBrowserContext() catch |err| switch (err) {
-        error.AlreadyExists => return cmd.sendError(-32000, "Cannot have more than one browser context at a time"),
+        error.AlreadyExists => return cmd.sendError(-32000, "Cannot have more than one browser context at a time", .{}),
         else => return err,
     };
 
@@ -102,7 +102,7 @@ fn disposeBrowserContext(cmd: anytype) !void {
     })) orelse return error.InvalidParams;
 
     if (cmd.cdp.disposeBrowserContext(params.browserContextId) == false) {
-        return cmd.sendError(-32602, "No browser context with the given id found");
+        return cmd.sendError(-32602, "No browser context with the given id found", .{});
     }
     try cmd.sendResult(null, .{});
 }