fix(server): launcher preflight and service install explain which t3 ran

apps/server/src/cli/service.ts

@@ -1,4 +1,9 @@
-import { HostProcessPlatform } from "@t3tools/shared/hostProcess";
+import {
+  HostProcessArguments,
+  HostProcessExecutablePath,
+  HostProcessIsExecutable,
+  HostProcessPlatform,
+} from "@t3tools/shared/hostProcess";
 import * as Console from "effect/Console";
 import * as Effect from "effect/Effect";
 import * as Layer from "effect/Layer";
@@ -110,6 +115,12 @@ const runServiceCommand = Effect.fn("cli.service.run")(function* <A, E>(
   return yield* run.pipe(Effect.provide(bootServiceLayer(config)));
 });
 
+/** The running CLI's path, so a stale `t3` earlier on PATH is visible. */
+const runningCliPath = Effect.gen(function* () {
+  if (yield* HostProcessIsExecutable) return yield* HostProcessExecutablePath;
+  return (yield* HostProcessArguments)[1] ?? (yield* HostProcessExecutablePath);
+});
+
 const serviceReconcileFlags = {
   ...projectLocationFlags,
   allowDowngrade: Flag.Boolean("allow-downgrade").pipe(
@@ -127,7 +138,7 @@ const serviceInstallCommand = Command.make("install", serviceReconcileFlags).pip
         const result = yield* reconcileService({ allowDowngrade: flags.allowDowngrade });
         if (!result.changed) {
           yield* Console.log(
-            `T3 Code service is already installed with t3@${packageJson.version}.`,
+            `T3 Code service is already installed with t3@${packageJson.version} (${yield* runningCliPath}).`,
           );
           return;
         }
@@ -153,7 +164,9 @@ const serviceUpdateCommand = Command.make("update", serviceReconcileFlags).pipe(
         );
         const result = yield* reconcileService({ allowDowngrade: flags.allowDowngrade });
         if (!result.changed) {
-          yield* Console.log(`T3 Code service is already using t3@${packageJson.version}.`);
+          yield* Console.log(
+            `T3 Code service is already using t3@${packageJson.version} (${yield* runningCliPath}).`,
+          );
           return;
         }
         yield* Console.log(

apps/server/src/cloud/servicePreflight.test.ts

@@ -4,18 +4,18 @@ import { runServicePreflight } from "./servicePreflight.ts";
 import { SERVICE_LAUNCHER_PROTOCOL } from "./serviceProtocol.ts";
 
 it.each([1, 2])("blocks legacy launcher protocol %i", (launcherProtocol) => {
-  expect(
-    runServicePreflight({
-      databasePath: "/missing/state.sqlite",
-      launcherProtocol,
-      version: "1.2.3",
-    }),
-  ).toEqual({
-    status: "blocked",
+  const result = runServicePreflight({
+    databasePath: "/missing/state.sqlite",
+    launcherProtocol,
     version: "1.2.3",
-    reason:
-      "This release requires a newer T3 Code service launcher. Update it on the server machine.",
   });
+  expect(result).toMatchObject({ status: "blocked", version: "1.2.3" });
+  const reason = result.status === "blocked" ? result.reason : "";
+  expect(reason).toContain(`needs service launcher protocol ${SERVICE_LAUNCHER_PROTOCOL}`);
+  expect(reason).toContain(`offered protocol ${launcherProtocol}`);
+  expect(reason).toContain("T3CODE_VERSION=1.2.3 sh");
+  expect(reason).toContain("`t3 service install`");
+  expect(reason).toContain("`which -a t3`");
 });
 
 it("accepts the current launcher protocol", () => {

apps/server/src/cloud/servicePreflight.ts

@@ -24,8 +24,12 @@ export function runServicePreflight(input: {
     return {
       status: "blocked",
       version,
-      reason:
-        "This release requires a newer T3 Code service launcher. Update it on the server machine.",
+      reason: [
+        `t3@${version} needs service launcher protocol ${SERVICE_LAUNCHER_PROTOCOL}, but the service on the server machine offered protocol ${input.launcherProtocol}.`,
+        `On that machine, install this exact version with \`curl -fsSL https://t3.codes/install.sh | T3CODE_VERSION=${version} sh\`, then run \`t3 service install\`.`,
+        "`t3 service update` and `t3 update` without a version keep whichever `t3` is first on PATH, `npx t3@latest` installs the latest stable release instead, and upgrading the desktop app does not replace it.",
+        `If \`t3 --version\` does not print ${version}, check \`which -a t3\`.`,
+      ].join(" "),
     };
   }