diff --git a/site/src/pages/WorkspaceSettingsPage/WorkspaceParametersPage/WorkspaceParametersPageExperimental.tsx b/site/src/pages/WorkspaceSettingsPage/WorkspaceParametersPage/WorkspaceParametersPageExperimental.tsx
index 8350a35d01..0178a4e6a2 100644
--- a/site/src/pages/WorkspaceSettingsPage/WorkspaceParametersPage/WorkspaceParametersPageExperimental.tsx
+++ b/site/src/pages/WorkspaceSettingsPage/WorkspaceParametersPage/WorkspaceParametersPageExperimental.tsx
@@ -96,11 +96,18 @@ const WorkspaceParametersPageExperimental: FC = () => {
 			return;
 		}
 
-		if (!initialParamsSentRef.current && response.parameters?.length > 0) {
-			sendInitialParameters();
+		// Skip stale responses. If we've already sent a newer request,
+		// this response contains outdated parameter values that would
+		// overwrite the user's more recent input.
+		if (response.id < wsResponseId.current) {
+			return;
 		}
 
 		setLatestResponse(response);
+
+		if (!initialParamsSentRef.current && response.parameters?.length > 0) {
+			sendInitialParameters();
+		}
 	});
 
 	useEffect(() => {
@@ -197,7 +204,7 @@ const WorkspaceParametersPageExperimental: FC = () => {
 
 	if (
 		latestBuildParametersLoading ||
-		!latestResponse ||
+		(!latestResponse && !wsError) ||
 		(ws.current && ws.current.readyState === WebSocket.CONNECTING)
 	) {
 		return <Loader />;
@@ -244,7 +251,7 @@ const WorkspaceParametersPageExperimental: FC = () => {
 					autofillParameters={autofillParameters}
 					canChangeVersions={canChangeVersions}
 					parameters={sortedParams}
-					diagnostics={latestResponse.diagnostics}
+					diagnostics={latestResponse?.diagnostics ?? []}
 					isSubmitting={updateParameters.isPending}
 					onSubmit={handleSubmit}
 					onCancel={() =>
diff --git a/site/src/pages/WorkspaceSettingsPage/WorkspaceParametersPage/WorkspaceParametersPageViewExperimental.tsx b/site/src/pages/WorkspaceSettingsPage/WorkspaceParametersPage/WorkspaceParametersPageViewExperimental.tsx
index bdb6bfd382..9be64b2cc3 100644
--- a/site/src/pages/WorkspaceSettingsPage/WorkspaceParametersPage/WorkspaceParametersPageViewExperimental.tsx
+++ b/site/src/pages/WorkspaceSettingsPage/WorkspaceParametersPage/WorkspaceParametersPageViewExperimental.tsx
@@ -9,6 +9,7 @@ import { Label } from "components/Label/Label";
 import { Link } from "components/Link/Link";
 import { Spinner } from "components/Spinner/Spinner";
 import { useFormik } from "formik";
+import { useDebouncedFunction } from "hooks/debounce";
 import { useSyncFormParameters } from "modules/hooks/useSyncFormParameters";
 import {
 	DynamicParameter,
@@ -16,6 +17,7 @@ import {
 	useValidationSchemaForDynamicParameters,
 } from "modules/workspaces/DynamicParameter/DynamicParameter";
 import type { FC } from "react";
+import { cn } from "utils/cn";
 import { docs } from "utils/docs";
 import type { AutofillBuildParameter } from "utils/richParameters";
 
@@ -67,6 +69,23 @@ export const WorkspaceParametersPageViewExperimental: FC<
 		workspace.template_require_active_version &&
 		!canChangeVersions;
 
+	// Debounce websocket sends to avoid stale responses overwriting
+	// the form while the user is still typing.
+	const { debounced: sendDynamicParamsRequest } = useDebouncedFunction(
+		(parameter: PreviewParameter, value: string) => {
+			const formInputs: Record<string, string> = {};
+			const formParameters = form.values.rich_parameter_values ?? [];
+			for (const param of formParameters) {
+				if (param?.name && param?.value) {
+					formInputs[param.name] = param.value;
+				}
+			}
+			formInputs[parameter.name] = value;
+			sendMessage(formInputs);
+		},
+		500,
+	);
+
 	const handleChange = async (
 		parameter: PreviewParameter,
 		parameterField: string,
@@ -79,29 +98,27 @@ export const WorkspaceParametersPageViewExperimental: FC<
 		sendDynamicParamsRequest(parameter, value);
 	};
 
-	const sendDynamicParamsRequest = (
-		parameter: PreviewParameter,
-		value: string,
-	) => {
-		const formInputs: Record<string, string> = {};
-		const parameters = form.values.rich_parameter_values ?? [];
-		for (const param of parameters) {
-			if (param?.name && param?.value) {
-				formInputs[param.name] = param.value;
-			}
-		}
-
-		formInputs[parameter.name] = value;
-
-		sendMessage(formInputs);
-	};
-
 	useSyncFormParameters({
 		parameters,
 		formValues: form.values.rich_parameter_values ?? [],
 		setFieldValue: form.setFieldValue,
 	});
 
+	// True when the form holds values the backend hasn't evaluated
+	// yet (debounce pending or WS round-trip in flight).
+	const hasUnsyncedParameters = (form.values.rich_parameter_values ?? []).some(
+		(formParam) => {
+			const responseParam = parameters.find((p) => p.name === formParam.name);
+			if (!responseParam) {
+				return true;
+			}
+			const responseValue = responseParam.value.valid
+				? responseParam.value.value
+				: "";
+			return formParam.value !== responseValue;
+		},
+	);
+
 	const hasIncompatibleParameters = parameters.some((parameter) => {
 		if (!parameter.mutable && parameter.diagnostics.length > 0) {
 			return true;
@@ -155,12 +172,12 @@ export const WorkspaceParametersPageViewExperimental: FC<
 					{diagnostics.map((diagnostic, index) => (
 						<div
 							key={`diagnostic-${diagnostic.summary}-${index}`}
-							className={`text-xs flex flex-col rounded-md border px-4 pb-3 border-solid
-								${
-									diagnostic.severity === "error"
-										? " text-content-destructive border-border-destructive"
-										: " text-content-warning border-border-warning"
-								}`}
+							className={cn(
+								"text-xs flex flex-col rounded-md border px-4 pb-3 border-solid",
+								diagnostic.severity === "error"
+									? " text-content-destructive border-border-destructive"
+									: " text-content-warning border-border-warning",
+							)}
 						>
 							<div className="flex items-center m-0">
 								<p className="font-medium">{diagnostic.summary}</p>
@@ -248,6 +265,7 @@ export const WorkspaceParametersPageViewExperimental: FC<
 						disabled={
 							isSubmitting ||
 							disabled ||
+							hasUnsyncedParameters ||
 							diagnostics.some(
 								(diagnostic) => diagnostic.severity === "error",
 							) ||