Hmbown/CodeWhale · error

Command is required

Error message

Command is required

What it means

Returned by run_sandbox_command when the command vector is empty, so split_first() yields no program to execute. It is a usage-contract error: the sandbox runner requires at least one element (the program) before it can build a CommandSpec. The policy, cwd, and timeout are parsed first, so those must already be valid.

Source

Thrown at crates/tui/src/lib.rs:8916

        exclude_slash_tmp,
        cwd,
        timeout_ms,
        command,
    } = args.command;

    let policy = parse_sandbox_policy(
        &policy,
        network,
        writable_root,
        exclude_tmpdir,
        exclude_slash_tmp,
    )?;
    let cwd = cwd.unwrap_or_else(|| std::env::current_dir().unwrap_or_else(|_| PathBuf::from(".")));
    let timeout = Duration::from_millis(timeout_ms.clamp(1000, 600_000));

    let (program, args) = command
        .split_first()
        .ok_or_else(|| anyhow::anyhow!("Command is required"))?;
    let spec =
        CommandSpec::program(program, args.to_vec(), cwd.clone(), timeout).with_policy(policy);
    let manager = SandboxManager::new();
    let exec_env = manager.prepare(&spec);

    let mut cmd = Command::new(exec_env.program());
    cmd.args(exec_env.args())
        .current_dir(&exec_env.cwd)
        .stdout(Stdio::piped())
        .stderr(Stdio::piped());
    child_env::apply_to_command(&mut cmd, child_env::string_map_env(&exec_env.env));

    let mut child = cmd
        .spawn()
        .map_err(|e| anyhow::anyhow!("Failed to run command: {e}"))?;
    let stdout_handle = child
        .stdout
        .take()

View on GitHub (pinned to 8880682c63)

Solutions

1. Pass a non-empty command: at minimum the program name, followed by its arguments
2. If driving SandboxCommand::Run programmatically, assert !command.is_empty() before calling
3. Tighten the CLI definition to require at least one value (num_args(1..) with a non-empty value_parser) so the error surfaces at parse time with clap's own message

Example fix

// before: empty argv reaches the runner
let (program, args) = command.split_first()
    .ok_or_else(|| anyhow::anyhow!("Command is required"))?;
// after: reject at the CLI boundary
#[arg(required = true, num_args = 1..)]
command: Vec<String>,

// Rust: gate before dispatch
if command.is_empty() {
    return Err(anyhow::anyhow!("sandbox run requires a program plus optional args"));
}

// Narrow an optional command into a guaranteed non-empty invocation
fn as_invocation(cmd: &[String]) -> Option<(&str, &[String])> {
    cmd.split_first().map(|(p, a)| (p.as_str(), a))
}

When it happens

Trigger: Invoking the sandbox run subcommand with an empty command list: `--command=` with an empty value, an argv built by a script where a variable expands to nothing (unquoted empty shell variable), or a programmatic caller passing Vec::new() as command to SandboxCommand::Run.

Common situations: Shell scripts forwarding unset variables into the CLI, wrapper tools that split an empty string into zero arguments, or clap arg definitions allowing zero values (num_args(0..)) for the command field.

Related errors

• Usage: node scripts/release/assemble-release-assets.js INP
• Invalid GitHub repository: ${repo}
• Invalid release tag: ${tag}
• Usage: node scripts/release/ensure-release-assets-absent.js
• unknown argument: ${arg}

AI-assisted analysis of Hmbown/CodeWhale@8880682c63 (2026-08-16). Data as JSON: /api/errors/4da9d6cae8fb84ca. Report an issue: GitHub.