A seat's verb keeps a node of its own; only a module's tool gives it to the subject

The console moved every call's node into the subject (ADR 0159), so mesh-controller.push {node: x}
became a call to the seat's verb on machine x, which nothing serves — the mesh's own verbs could not
be given a machine from the console at all. A role's verb takes no machine from the console; its
arguments are its own.

src/mcp.ts

@@ -15,7 +15,7 @@
  */
 import type { Broker } from "@novox/mesh-sdk/messaging";
 
-import { callTool, seatsIn, toolsOn, whyItFailed, type Listing, type Seats } from "./client.js";
+import { callTool, seatsIn, toolKey, toolsOn, whyItFailed, type Listing, type Seats } from "./client.js";
 
 /** The protocol version this speaks. Stated, because a host that wants another should be told so
  *  rather than discovering it through a shape it did not expect. */
@@ -134,13 +134,17 @@ export function mcpSurface(bus: Broker, who: string): Surface {
           const given = String(request.params?.name ?? "");
           const args = { ...((request.params?.arguments as Record<string, unknown> | undefined) ?? {}) };
           // The machine, when the caller names one, travels in the subject and never reaches the
-          // module's arguments (novox/hq ADR 0159).
+          // module's arguments (novox/hq ADR 0159) — for a module's tool. A seat's verb takes no
-          const node = typeof args.node === "string" && args.node !== "" ? args.node : "";
+          // machine from the console (the seat's scope decides), so a `node` among its arguments
-          delete args.node;
+          // is the verb's own, as `push` and `assign` take one, and is handed through untouched.
+          const have = await listing().catch(() => undefined);
+          const roles = have && seatsIn(have);
+          const isSeatVerb = roles ? toolKey(given.split("@", 1)[0], roles).startsWith("seat:") : false;
+          const node = !isSeatVerb && typeof args.node === "string" && args.node !== "" ? args.node : "";
+          if (!isSeatVerb) delete args.node;
           const name = node && !given.includes("@") ? `${given}@${node}` : given;
           try {
-            const have = await listing().catch(() => undefined);
+            const { result, node: answeredBy } = await callTool(bus, name, args, roles, have);
-            const { result, node: answeredBy } = await callTool(bus, name, args, have && seatsIn(have), have);
             // Text, because that is what every host renders. The content is the module's answer
             // as JSON, unshaped: an adapter that flattened it would be deciding what matters in
             // somebody else's answer. Which machine answered follows it as its own line.

test/mcp.test.ts

@@ -30,9 +30,13 @@ async function aMeshAndACredential(t: { after: (fn: () => Promise<void> | void)
   await shop.handle("price", async (body: { of?: string }) => ({ of: body.of ?? "nothing", cost: 12 }));
   const controller = await connectNats({ url: url!, module: "mesh-controller" });
   await controller.handle("seat:mesh-controller.tools", async () => ({
-    seats: [{ seat: "mesh-controller", scope: "mesh", tools: [{ name: "status", description: "what is wrong", input: {} }] }],
+    seats: [{ seat: "mesh-controller", scope: "mesh", tools: [
+      { name: "status", description: "what is wrong", input: {} },
+      { name: "push", description: "tell a machine", input: { node: { type: "string" } } },
+    ] }],
   }));
   await controller.handle("seat:mesh-controller.status", async () => ({ output: "all quiet", ok: true }));
+  await controller.handle("seat:mesh-controller.push", async (body: { node?: string }) => ({ told: body.node ?? "nobody" }));
   t.after(async () => {
     await catalogue.close();
     await shop.close();
@@ -95,7 +99,7 @@ test("a host initialises, lists the mesh's tools and calls one", async (t) => {
   assert.match(hello.instructions, /ada/, "the handshake says whose authority a call is made under");
 
   const listed = byId.get(2)!.result.tools;
-  assert.deepEqual(listed.map((x: { name: string }) => x.name), ["mesh-controller.status", "shop.price"],
+  assert.deepEqual(listed.map((x: { name: string }) => x.name), ["mesh-controller.push", "mesh-controller.status", "shop.price"],
     "the modules' tools and the roles', named the way a person names them");
   const price = listed[1];
   assert.ok(price.inputSchema, "a tool with no schema is one an agent cannot call");
@@ -141,6 +145,19 @@ test("a method this surface does not have is refused, and a notification is not"
   assert.match(replies[0].error.message, /resources\/list/);
 });
 
+// A seat's verb that takes a machine as its own argument — `push <node>` — keeps it: the console
+// moves `node` into the subject for a module's tool only (ADR 0159), never for a role's verb.
+test("a seat's verb keeps a node of its own; only a module's tool gives it to the subject", async (t) => {
+  if (!url) return t.skip("MESH_TEST_NATS unset");
+  const credential = await aMeshAndACredential(t);
+  const replies = await driving(credential, [
+    { jsonrpc: "2.0", id: 1, method: "tools/call", params: { name: "mesh-controller.push", arguments: { node: "anchor" } } },
+  ]);
+  const result = replies[0].result;
+  assert.ok(!result.isError, JSON.stringify(replies[0]));
+  assert.deepEqual(JSON.parse(result.content[0].text), { told: "anchor" });
+});
+
 test("a host calls the mesh's own verb through the seat", async (t) => {
   if (!url) return t.skip("MESH_TEST_NATS unset");
   const credential = await aMeshAndACredential(t);