nikivdev/code · error

No tasks specified

Error message

No tasks specified

What it means

run_parallel is the library-level parallel executor; it rejects an empty task vector up front. It mirrors the CLI guard in run but applies to direct programmatic callers.

Source

Thrown at src/parallel.rs:429

            }
        }

        // Show cursor
        print!("{}", SHOW_CURSOR);
        let _ = io::stdout().flush();

        self.first_failure_code.lock().await.unwrap_or(0)
    }
}

/// Run tasks in parallel with pretty output.
pub async fn run_parallel(
    tasks: Vec<(&str, &str)>,
    max_jobs: usize,
    fail_fast: bool,
) -> Result<()> {
    if tasks.is_empty() {
        bail!("No tasks specified");
    }

    let tasks: Vec<Task> = tasks
        .into_iter()
        .map(|(label, cmd)| Task::new(label, cmd))
        .collect();

    let runner = Arc::new(ParallelRunner::new(tasks, max_jobs, fail_fast));
    let exit_code = runner.run().await;

    if exit_code != 0 {
        std::process::exit(exit_code);
    }

    Ok(())
}

/// CLI entry point for `f parallel`.

View on GitHub (pinned to a747e741ae)

Solutions

1. Ensure the tasks vector has at least one entry before calling run_parallel.
2. If callers may produce empty lists, check tasks.is_empty() first and skip/short-circuit gracefully.

Example fix

// before
run_parallel(&[], 4, false).await?;

// after
let tasks = build_tasks();
if !tasks.is_empty() {
    run_parallel(&tasks, 4, false).await?;
}

if tasks.is_empty() {
    eprintln!("nothing to run; skipping run_parallel");
    return Ok(());
}
run_parallel(&tasks, max_jobs, fail_fast).await?;

When it happens

Trigger: Calling run_parallel(vec![], max_jobs, fail_fast) — e.g. a caller that built its task list from an empty filter result.

Common situations: Programmatic use where the caller passes user input through without checking it produced at least one (label, command) pair.

Related errors

• No prompt provided. Usage: f agents run {} "your prompt here
• No prompt provided for flow agent.
• agent run requires a non-empty query
• empty resolver command for {}
• resolver {} returned empty output for {}

AI-assisted analysis of nikivdev/code@a747e741ae (2026-09-01). Data as JSON: /api/errors/d1d750577347238f. Report an issue: GitHub.