diff --git a/codex-rs/cli/src/main.rs b/codex-rs/cli/src/main.rs
index f5ef489cb0..60d1566142 100644
--- a/codex-rs/cli/src/main.rs
+++ b/codex-rs/cli/src/main.rs
@@ -3223,34 +3223,6 @@ mod tests {
         assert!(remove_result.is_err());
     }
 
-    #[test]
-    fn full_auto_no_longer_parses_at_top_level() {
-        let result = MultitoolCli::try_parse_from(["codex", "--full-auto"]);
-
-        assert!(result.is_err());
-    }
-
-    #[test]
-    fn exec_full_auto_reports_migration_path() {
-        let cli = MultitoolCli::try_parse_from(["codex", "exec", "--full-auto", "summarize"])
-            .expect("exec should accept removed flag long enough to report a migration path");
-        let Some(Subcommand::Exec(exec)) = cli.subcommand else {
-            panic!("expected exec subcommand");
-        };
-
-        assert_eq!(
-            exec.removed_full_auto_warning(),
-            Some("warning: `--full-auto` is deprecated; use `--sandbox workspace-write` instead.")
-        );
-    }
-
-    #[test]
-    fn sandbox_full_auto_no_longer_parses() {
-        let result = MultitoolCli::try_parse_from(["codex", "sandbox", "--full-auto", "--"]);
-
-        assert!(result.is_err());
-    }
-
     fn sample_exit_info(conversation_id: Option<&str>, thread_name: Option<&str>) -> AppExitInfo {
         let token_usage = TokenUsage {
             output_tokens: 2,
diff --git a/codex-rs/exec/src/cli.rs b/codex-rs/exec/src/cli.rs
index 53124c11a5..694630c9b0 100644
--- a/codex-rs/exec/src/cli.rs
+++ b/codex-rs/exec/src/cli.rs
@@ -39,16 +39,6 @@ pub struct Cli {
     #[arg(long = "ignore-rules", global = true, default_value_t = false)]
     pub ignore_rules: bool,
 
-    /// Legacy compatibility trap for the removed `--full-auto` flag.
-    #[arg(
-        long = "full-auto",
-        hide = true,
-        global = true,
-        default_value_t = false,
-        conflicts_with = "dangerously_bypass_approvals_and_sandbox"
-    )]
-    pub removed_full_auto: bool,
-
     /// Path to a JSON Schema file describing the model's final response shape.
     #[arg(long = "output-schema", value_name = "FILE", global = true)]
     pub output_schema: Option<PathBuf>,
@@ -99,18 +89,6 @@ impl std::ops::DerefMut for Cli {
     }
 }
 
-impl Cli {
-    pub fn removed_full_auto_warning(&self) -> Option<&'static str> {
-        if self.removed_full_auto {
-            return Some(
-                "warning: `--full-auto` is deprecated; use `--sandbox workspace-write` instead.",
-            );
-        }
-
-        None
-    }
-}
-
 #[derive(Debug, Default)]
 pub struct ExecSharedCliOptions(SharedCliOptions);
 
diff --git a/codex-rs/exec/src/cli_tests.rs b/codex-rs/exec/src/cli_tests.rs
index 524067dd66..f17707bf77 100644
--- a/codex-rs/exec/src/cli_tests.rs
+++ b/codex-rs/exec/src/cli_tests.rs
@@ -73,13 +73,3 @@ fn parses_config_isolation_flags() {
     assert!(cli.ignore_user_config);
     assert!(cli.ignore_rules);
 }
-
-#[test]
-fn removed_full_auto_flag_reports_migration_path() {
-    let cli = Cli::parse_from(["codex-exec", "--full-auto", "summarize"]);
-
-    assert_eq!(
-        cli.removed_full_auto_warning(),
-        Some("warning: `--full-auto` is deprecated; use `--sandbox workspace-write` instead.")
-    );
-}
diff --git a/codex-rs/exec/src/lib.rs b/codex-rs/exec/src/lib.rs
index 31a502da31..962dba866a 100644
--- a/codex-rs/exec/src/lib.rs
+++ b/codex-rs/exec/src/lib.rs
@@ -238,11 +238,6 @@ fn exec_stderr_env_filter() -> EnvFilter {
 }
 
 pub async fn run_main(cli: Cli, arg0_paths: Arg0DispatchPaths) -> anyhow::Result<()> {
-    #[allow(clippy::print_stderr)]
-    if let Some(message) = cli.removed_full_auto_warning() {
-        eprintln!("{message}");
-    }
-
     if let Err(err) = set_default_originator("codex_exec".to_string()) {
         tracing::warn!(?err, "Failed to set codex exec originator override {err:?}");
     }
@@ -255,7 +250,6 @@ pub async fn run_main(cli: Cli, arg0_paths: Arg0DispatchPaths) -> anyhow::Result
         ephemeral,
         ignore_user_config,
         ignore_rules,
-        removed_full_auto,
         color,
         last_message_file,
         json: json_mode,
@@ -290,9 +284,7 @@ pub async fn run_main(cli: Cli, arg0_paths: Arg0DispatchPaths) -> anyhow::Result
         .with_writer(std::io::stderr)
         .with_filter(exec_stderr_env_filter());
 
-    let sandbox_mode = if removed_full_auto {
-        Some(SandboxMode::WorkspaceWrite)
-    } else if dangerously_bypass_approvals_and_sandbox {
+    let sandbox_mode = if dangerously_bypass_approvals_and_sandbox {
         Some(SandboxMode::DangerFullAccess)
     } else {
         sandbox_mode_cli_arg.map(Into::<SandboxMode>::into)
@@ -460,7 +452,7 @@ pub async fn run_main(cli: Cli, arg0_paths: Arg0DispatchPaths) -> anyhow::Result
     };
     let config = build_exec_config(
         overrides,
-        dangerously_bypass_approvals_and_sandbox || removed_full_auto,
+        dangerously_bypass_approvals_and_sandbox,
         build_config,
     )
     .await?;
diff --git a/codex-rs/exec/tests/suite/approval_policy.rs b/codex-rs/exec/tests/suite/approval_policy.rs
index b04bf9a6b6..de650ef978 100644
--- a/codex-rs/exec/tests/suite/approval_policy.rs
+++ b/codex-rs/exec/tests/suite/approval_policy.rs
@@ -56,14 +56,3 @@ async fn exec_bypass_preserves_never_for_auto_review_config() -> anyhow::Result<
 
     Ok(())
 }
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-async fn exec_full_auto_preserves_never_for_auto_review_config() -> anyhow::Result<()> {
-    let stderr = run_exec_with_auto_review_config(&["--full-auto"]).await?;
-    assert!(
-        stderr.contains("approval: never"),
-        "stderr missing full-auto approval mode: {stderr}"
-    );
-
-    Ok(())
-}