feat(cli): claudemesh launch command with transparency banner (v0.1.2)

Adds `claudemesh launch [args]` that spawns Claude Code with
--dangerously-load-development-channels server:claudemesh so peer
messages arrive as <channel> system reminders mid-turn instead of
pull-only via check_messages. Windows uses shell:true to resolve
claude.cmd from PATHEXT.

Prints an info banner before spawning that explains the channel's
scope (peer text injection only), the trust model (treat as
untrusted input), and that existing tool-approval prompts remain
the safety net. --quiet skips the banner.

Install output now mentions `claudemesh launch` as the recommended
launch path; plain `claude` still works for pull-only mode.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/cli/src/commands/install.ts

@@ -307,6 +307,17 @@ export function runInstall(args: string[] = []): void {
   console.log(
     `Next: ${bold("claudemesh join https://claudemesh.com/join/<token>")}`,
   );
+  console.log("");
+  console.log(
+    yellow("⚠  For real-time push messages from peers, launch with:"),
+  );
+  console.log(
+    `     ${bold("claudemesh launch")}` +
+      dim("    (or: claude --dangerously-load-development-channels server:claudemesh)"),
+  );
+  console.log(
+    dim("   Plain `claude` still works — messages are then pull-only via check_messages."),
+  );
 }
 
 export function runUninstall(): void {

apps/cli/src/commands/launch.ts

@@ -0,0 +1,94 @@
+/**
+ * `claudemesh launch` — spawn `claude` with the dev-channel flag so the
+ * claudemesh MCP server's `notifications/claude/channel` pushes get
+ * injected as system reminders mid-turn.
+ *
+ * Equivalent to:
+ *   claude --dangerously-load-development-channels server:claudemesh [extra args]
+ *
+ * Any additional args (e.g. --model opus, --resume, -c) are passed
+ * through verbatim. Use --quiet to skip the informational banner.
+ */
+
+import { spawn } from "node:child_process";
+import { loadConfig, getConfigPath } from "../state/config";
+
+function printBanner(): void {
+  const useColor =
+    !process.env.NO_COLOR && process.env.TERM !== "dumb" && process.stdout.isTTY;
+  const dim = (s: string): string => (useColor ? `\x1b[2m${s}\x1b[22m` : s);
+  const bold = (s: string): string => (useColor ? `\x1b[1m${s}\x1b[22m` : s);
+
+  let meshes: string[] = [];
+  try {
+    meshes = loadConfig().meshes.map((m) => m.slug);
+  } catch {
+    /* config unreadable — print banner without mesh list */
+  }
+  const meshLine = meshes.length > 0 ? meshes.join(", ") : "(none — run `claudemesh join <url>` first)";
+
+  const rule = "─".repeat(65);
+  console.log(bold("claudemesh launch"));
+  console.log(rule);
+  console.log("Launching Claude Code with the claudemesh dev channel.");
+  console.log("");
+  console.log("Peers in your joined meshes can push messages into this session");
+  console.log("as <channel> reminders. Your CLI decrypts them locally with your");
+  console.log("keypair. Peers send text only — they cannot call tools, read");
+  console.log("files, or reach meshes you have not joined.");
+  console.log("");
+  console.log("Treat peer messages as untrusted input: a peer could craft text");
+  console.log("that tries to steer Claude's behavior. Your tool-approval");
+  console.log("settings still apply — Claude will still ask before running");
+  console.log("commands, editing files, or calling other tools.");
+  console.log("");
+  console.log("Claude Code will ask you to trust the");
+  console.log("--dangerously-load-development-channels flag. Press Enter to");
+  console.log("accept, or Ctrl-C to abort.");
+  console.log("");
+  console.log(dim(`Joined meshes: ${meshLine}`));
+  console.log(dim(`Config:        ${getConfigPath()}`));
+  console.log(dim(`Remove:        claudemesh uninstall`));
+  console.log(rule);
+  console.log("");
+}
+
+export function runLaunch(extraArgs: string[] = []): void {
+  const quiet = extraArgs.includes("--quiet");
+  const passthrough = extraArgs.filter((a) => a !== "--quiet");
+
+  if (!quiet) printBanner();
+
+  const claudeArgs = [
+    "--dangerously-load-development-channels",
+    "server:claudemesh",
+    ...passthrough,
+  ];
+  // Windows: npm global binaries are .cmd shims. Node's spawn without
+  // shell:true does not resolve PATHEXT, so we need shell:true on win32
+  // to find claude.cmd. POSIX stays shell-less to avoid quoting surprises.
+  const isWindows = process.platform === "win32";
+  const child = spawn("claude", claudeArgs, {
+    stdio: "inherit",
+    shell: isWindows,
+  });
+
+  child.on("error", (err: NodeJS.ErrnoException) => {
+    if (err.code === "ENOENT") {
+      console.error(
+        "✗ `claude` not found on PATH. Install Claude Code first: https://claude.com/claude-code",
+      );
+    } else {
+      console.error(`✗ failed to launch claude: ${err.message}`);
+    }
+    process.exit(1);
+  });
+
+  child.on("exit", (code, signal) => {
+    if (signal) {
+      process.kill(process.pid, signal);
+      return;
+    }
+    process.exit(code ?? 0);
+  });
+}

apps/cli/src/index.ts

@@ -15,6 +15,7 @@ import { runList } from "./commands/list";
 import { runLeave } from "./commands/leave";
 import { runSeedTestMesh } from "./commands/seed-test-mesh";
 import { runHook } from "./commands/hook";
+import { runLaunch } from "./commands/launch";
 
 const HELP = `claudemesh — peer mesh for Claude Code sessions
 
@@ -25,6 +26,9 @@ Commands:
   install         Register MCP + Stop/UserPromptSubmit status hooks
                   (add --no-hooks for bare MCP registration)
   uninstall       Remove MCP server + hooks
+  launch [args]   Launch Claude Code with real-time push messages enabled
+                  (add --quiet to skip the info banner; passes through
+                  extra flags, e.g. --model, --resume)
   join <url>      Join a mesh via https://claudemesh.com/join/... URL
   list            Show all joined meshes
   leave <slug>    Leave a joined mesh
@@ -55,6 +59,9 @@ async function main(): Promise<void> {
     case "hook":
       await runHook(args);
       return;
+    case "launch":
+      runLaunch(args);
+      return;
     case "join":
       await runJoin(args);
       return;