feat(tty): Add --no-input flag and TTY checks for interactive commands

src/auth.rs

@@ -261,6 +261,9 @@ pub fn login() {
     // Check if already authenticated
     if is_already_signed_in(&profile_config) {
         println!("{}", "You are already signed in.".green());
+        if !crate::util::is_interactive() {
+            return;
+        }
         print!("Do you want to log in again? [y/N] ");
         use std::io::Write;
         std::io::stdout().flush().unwrap();

src/connections_new.rs

@@ -260,6 +260,15 @@ fn walk_auth(schema: &Value) -> Map<String, Value> {
 // ── Entry point ───────────────────────────────────────────────────────────────
 
 pub fn run(workspace_id: &str) {
+    if !crate::util::is_interactive() {
+        eprintln!(
+            "error: 'connections new' is interactive and stdin is not a TTY. \
+             Use 'hotdata connections create list' to discover types and their config schemas, \
+             then 'hotdata connections create --name <n> --type <t> --config '{{…}}''."
+        );
+        std::process::exit(1);
+    }
+
     let api = ApiClient::new(Some(workspace_id));
 
     // Phase 1: Select connection type

src/main.rs

@@ -46,6 +46,10 @@ struct Cli {
     #[arg(long, global = true, hide = true)]
     debug: bool,
 
+    /// Disable interactive prompts; commands that need input will error instead
+    #[arg(long = "no-input", global = true)]
+    no_input: bool,
+
     #[command(subcommand)]
     command: Option<Commands>,
 }
@@ -134,6 +138,9 @@ fn main() {
     if cli.debug {
         util::set_debug(true);
     }
+    if cli.no_input {
+        util::set_no_input(true);
+    }
 
     let skip_skill_auto_update =
         cli.command.is_none() || matches!(&cli.command, Some(Commands::Skills { .. }));

src/util.rs

@@ -13,6 +13,27 @@ pub fn spinner(msg: &str) -> indicatif::ProgressBar {
     pb
 }
 
+static NO_INPUT: AtomicBool = AtomicBool::new(false);
+
+pub fn set_no_input(enabled: bool) {
+    NO_INPUT.store(enabled, Ordering::Relaxed);
+}
+
+/// Returns true if interactive prompts are usable. Returns false when:
+/// - the global `--no-input` flag was passed,
+/// - the `CI` env var is set (most CI runners set this),
+/// - stdin is not a TTY (piped, redirected, or invoked by an agent harness).
+pub fn is_interactive() -> bool {
+    if NO_INPUT.load(Ordering::Relaxed) {
+        return false;
+    }
+    if std::env::var_os("CI").is_some() {
+        return false;
+    }
+    use std::io::IsTerminal;
+    std::io::stdin().is_terminal()
+}
+
 static DEBUG: AtomicBool = AtomicBool::new(false);
 
 pub fn set_debug(enabled: bool) {

src/workspace.rs

@@ -43,6 +43,14 @@ pub fn set(workspace_id: Option<&str>) {
                 eprintln!("error: no workspaces available.");
                 std::process::exit(1);
             }
+            if !crate::util::is_interactive() {
+                eprintln!(
+                    "error: stdin is not a TTY; cannot prompt for selection. \
+                     Run 'hotdata workspaces list' to see available IDs, \
+                     then 'hotdata workspaces set <workspace_id>'."
+                );
+                std::process::exit(1);
+            }
             let options: Vec<String> = workspaces
                 .iter()
                 .map(|w| format!("{} ({})", w.name, w.public_id))