What causes "unsupported codex open action: {}" in nikivdev/code?

Use a supported action: `new`, `resume`, `recover-new`, or omit the action for the default

unsupported codex open action: {}

Error message

unsupported codex open action: {}

What it means

The codex open planner supports a fixed set of actions (resume/recover, new, recover-new, etc.). Any other action string reaching the dispatcher's `other =>` arm bails with the offending value. This is a defensive guard against unknown or future action variants.

Source

Thrown at src/ai.rs:11762

                plan.runtime_state_path.as_deref(),
                plan.trace.as_ref(),
            )? {
                Ok(())
            } else {
                bail!("failed to resume codex session {}", session_id);
            }
        }
        "new" | "recover-new" => {
            maybe_open_cursor_for_pr_feedback_check(plan);
            new_session_for_target(
                Provider::Codex,
                plan.prompt.as_deref(),
                Some(&launch_path),
                plan.runtime_state_path.as_deref(),
                plan.trace.as_ref(),
            )
        }
        other => bail!("unsupported codex open action: {}", other),
    }
}

fn maybe_open_cursor_for_pr_feedback_check(plan: &CodexOpenPlan) {
    let Some(query) = plan
        .query
        .as_deref()
        .map(str::trim)
        .filter(|value| !value.is_empty())
    else {
        return;
    };
    if !looks_like_pr_feedback_query(query) {
        return;
    }
    if env_flag_is_false("FLOW_OPEN_CURSOR_ON_PR_CHECK") {
        return;
    }

View on GitHub (pinned to a747e741ae)

Solutions

Use a supported action: `new`, `resume`, `recover-new`, or omit the action for the default
Fix the typo or update the script to current action names
Check `f codex open --help` for the accepted action list

Example fix

// before
f codex open my-session --action resme
// after
f codex open my-session --action resume

Defensive patterns

Strategy: validation

Validate before calling

const VALID_ACTIONS: &[&str] = &["new", "resume", "recover-new"];
if !VALID_ACTIONS.contains(&action.as_str()) {
    eprintln!("unsupported codex open action: {}", action);
    std::process::exit(2);
}

Type guard

fn is_valid_action(a: &str) -> bool {
    matches!(a, "new" | "resume" | "recover-new")
}

Prevention

Whitelist action names in wrapper scripts
Re-check `--help` after CLI upgrades before scripting actions
Use enums/constants, not raw strings, when building plans programmatically

When it happens

Trigger: Invoking `f codex open` with an unrecognized action value — typically via a wrapper, script, or config that builds the plan programmatically with a typo'd or outdated action name.

Common situations: Typo like `--action resme`; scripts written against an older CLI whose action names changed; downstream tooling (call_ok_surfaces_remote_error, login, rank_branches callers) passing an unexpected action.

Related errors

AI-assisted analysis of nikivdev/code@a747e741ae (2026-09-01). Data as JSON: /api/errors/fe57748bdbd4be52. Report an issue: GitHub.