Hmbown/CodeWhale · error · anyhow::Error

--web is mutually exclusive with --http and --mobile

Error message

--web is mutually exclusive with --http and --mobile

What it means

validate_serve_mode_selection: --web was combined with --http or --mobile; the web serve mode replaces rather than composes with those listeners, so the combination is rejected during CLI validation before any server starts.

Solutions

  1. Choose only --web, or only --http/--mobile, per invocation
  2. Run two separate codewhale serve processes if both surfaces are genuinely needed
  3. Use --web alone if the web interface was the goal

Example fix

// before
codewhale serve --web --http
// after
codewhale serve --web
Defensive patterns

Strategy: validation

Validate before calling

if web && (http || mobile) { eprintln!("--web cannot be combined"); std::process::exit(2); }

Try / catch

match result { Err(e) if e.to_string().contains("--web is mutually exclusive") => { eprintln!("{}", e); std::process::exit(2); }, other => other? }

Prevention

When it happens

Trigger: Invoking a serve/server subcommand with `--web` alongside `--http` or `--mobile` (e.g. `codewhale serve --web --http`).

Common situations: Wanting both the web UI and raw HTTP endpoint at once in one process; scripted flag accumulation; outdated docs or muscle memory from other tools.

Understand the failure class

Background: "mutually exclusive" flag errors: what "can't supply both nx and xx", "--raw is not compatible with -i" and "cannot be used with" mean, and how to fix them — this error's family across 29 libraries.

Related errors

AI-assisted analysis of Hmbown/CodeWhale@73e0f67d83 (2026-09-22). Data as JSON: /api/errors/ffb78eb39ba20ff8. Report an issue: GitHub.

Appendix: source

Thrown at crates/tui/src/lib.rs:1404

fn resolve_serve_bind_host(_mobile: bool, host: Option<String>) -> ServeBindHost {
    ServeBindHost {
        host: host.unwrap_or_else(|| "127.0.0.1".to_string()),
    }
}

fn validate_serve_mode_selection(
    mcp: bool,
    http: bool,
    mobile: bool,
    web: bool,
    acp: bool,
) -> Result<bool> {
    if http && mobile {
        bail!("--http and --mobile are mutually exclusive; choose one");
    }
    if web && (http || mobile) {
        bail!("--web is mutually exclusive with --http and --mobile");
    }
    let http_selected = http || mobile || web;
    let selected_modes = [mcp, http_selected, acp]
        .into_iter()
        .filter(|selected| *selected)
        .count();
    if selected_modes != 1 {
        bail!("Choose exactly one server mode: --mcp, --http/--mobile/--web, or --acp");
    }
    Ok(http_selected)
}

#[derive(Subcommand, Debug, Clone)]
enum McpCommand {
    /// List configured MCP servers
    List,
    /// Create a template MCP config at the configured path
    Init {

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