feat: codex sampler (#17784)

Add a pure sampler using the Codex auth and model config. To be used by
other binary such as tape recorder

codex-rs/cli/src/main.rs

@@ -40,11 +40,14 @@ mod app_cmd;
 mod desktop_app;
 mod marketplace_cmd;
 mod mcp_cmd;
+mod responses_cmd;
 #[cfg(not(windows))]
 mod wsl_paths;
 
 use crate::marketplace_cmd::MarketplaceCli;
 use crate::mcp_cmd::McpCli;
+use crate::responses_cmd::ResponsesCommand;
+use crate::responses_cmd::run_responses_command;
 
 use codex_core::config::Config;
 use codex_core::config::ConfigOverrides;
@@ -151,6 +154,10 @@ enum Subcommand {
     #[clap(hide = true)]
     ResponsesApiProxy(ResponsesApiProxyArgs),
 
+    /// Internal: send one raw Responses API payload through Codex auth.
+    #[clap(hide = true)]
+    Responses(ResponsesCommand),
+
     /// Internal: relay stdio to a Unix domain socket.
     #[clap(hide = true, name = "stdio-to-uds")]
     StdioToUds(StdioToUdsCommand),
@@ -1015,6 +1022,14 @@ async fn cli_main(arg0_paths: Arg0DispatchPaths) -> anyhow::Result<()> {
             tokio::task::spawn_blocking(move || codex_responses_api_proxy::run_main(args))
                 .await??;
         }
+        Some(Subcommand::Responses(ResponsesCommand {})) => {
+            reject_remote_mode_for_subcommand(
+                root_remote.as_deref(),
+                root_remote_auth_token_env.as_deref(),
+                "responses",
+            )?;
+            run_responses_command(root_config_overrides).await?;
+        }
         Some(Subcommand::StdioToUds(cmd)) => {
             reject_remote_mode_for_subcommand(
                 root_remote.as_deref(),
@@ -1666,6 +1681,15 @@ mod tests {
         );
     }
 
+    #[test]
+    fn responses_subcommand_is_hidden_from_help_but_parses() {
+        let help = MultitoolCli::command().render_help().to_string();
+        assert!(!help.contains("responses"));
+
+        let cli = MultitoolCli::try_parse_from(["codex", "responses"]).expect("parse");
+        assert!(matches!(cli.subcommand, Some(Subcommand::Responses(_))));
+    }
+
     fn sample_exit_info(conversation_id: Option<&str>, thread_name: Option<&str>) -> AppExitInfo {
         let token_usage = TokenUsage {
             output_tokens: 2,