diff --git a/src/cli/nodes-cli.coverage.test.ts b/src/cli/nodes-cli.coverage.test.ts
index 1800b727049..e261725f292 100644
--- a/src/cli/nodes-cli.coverage.test.ts
+++ b/src/cli/nodes-cli.coverage.test.ts
@@ -208,6 +208,19 @@ describe("nodes-cli coverage", () => {
     expect(runtimeErrors.at(-1)).toContain('command "system.run" is reserved for shell execution');
   });
 
+  it("rejects malformed nodes invoke params before opening a gateway call", async () => {
+    await expect(
+      sharedProgram.parseAsync(
+        ["nodes", "invoke", "--node", "mac-1", "--command", "canvas.eval", "--params", "not-json"],
+        { from: "user" },
+      ),
+    ).rejects.toThrow("__exit__:1");
+
+    expect(runtimeErrors.at(-1)).toContain("--params must be valid JSON.");
+    expect(callGateway).not.toHaveBeenCalled();
+    expect(lastNodeInvokeCall).toBeNull();
+  });
+
   it("invokes system.notify with provided fields", async () => {
     const invoke = await runNodesCommand([
       "nodes",
diff --git a/src/cli/nodes-cli/register.invoke.ts b/src/cli/nodes-cli/register.invoke.ts
index 1115cc411db..5fbbed1c984 100644
--- a/src/cli/nodes-cli/register.invoke.ts
+++ b/src/cli/nodes-cli/register.invoke.ts
@@ -17,6 +17,14 @@ import type { NodesRpcOpts } from "./types.js";
 
 const BLOCKED_NODE_INVOKE_COMMANDS = new Set(["system.run", "system.run.prepare"]);
 
+function parseNodeInvokeParams(value = "{}"): unknown {
+  try {
+    return JSON.parse(value) as unknown;
+  } catch {
+    throw new Error("--params must be valid JSON.");
+  }
+}
+
 /** Register direct node command invocation. */
 export function registerNodesInvokeCommands(nodes: Command) {
   nodesCallOpts(
@@ -30,9 +38,9 @@ export function registerNodesInvokeCommands(nodes: Command) {
       .option("--idempotency-key <key>", "Idempotency key (optional)")
       .action(async (opts: NodesRpcOpts) => {
         await runNodesCommand("invoke", async () => {
-          const nodeId = await resolveNodeId(opts, normalizeOptionalString(opts.node) ?? "");
+          const nodeQuery = normalizeOptionalString(opts.node) ?? "";
           const command = normalizeOptionalString(opts.command) ?? "";
-          if (!nodeId || !command) {
+          if (!nodeQuery || !command) {
             const { error } = getNodesTheme();
             defaultRuntime.error(error("--node and --command required"));
             defaultRuntime.exit(1);
@@ -43,7 +51,8 @@ export function registerNodesInvokeCommands(nodes: Command) {
               `command "${command}" is reserved for shell execution; use the exec tool with host=node instead`,
             );
           }
-          const params = JSON.parse(opts.params ?? "{}") as unknown;
+          const params = parseNodeInvokeParams(opts.params);
+          const nodeId = await resolveNodeId(opts, nodeQuery);
           const timeoutMs = parseOptionalNodePositiveInteger(
             opts.invokeTimeout,
             "--invoke-timeout",