Hmbown/CodeWhale · error

fleet task worker.model cannot be empty

Error message

fleet task {task_id} worker.model cannot be empty

What it means

The optional worker.model field, when present, must be non-empty. validate_worker_model returns Ok for None but bails on an empty or whitespace-only value. A blank model id would leave the worker without a usable model assignment.

Solutions

1. Set a concrete model id for worker.model
2. Delete the field (None) if the worker should inherit the default model
3. Convert empty strings to None before building the spec

Example fix

# before
model: "   "
# after
model: "gpt-4o"

fn model_present_ok(m: Option<&str>) -> bool { m.map_or(true, |v| !v.trim().is_empty()) }

fn clean_model(m: Option<&str>) -> Option<&str> { m.filter(|v| !v.trim().is_empty()) }

match validate_worker_model(task_id, value) { Err(e) if e.to_string().contains("cannot be empty") => *value = None, r => r? }

When it happens

Trigger: validate_worker_profile encounters task {task_id} where worker.model is Some("") or only whitespace.

Common situations: Templated specs where the model variable was empty; clearing the model in a UI which wrote ""; YAML `model: ""` left from a template.

Understand the failure class

Background: "must not be empty", "cannot be empty" — required-field validation errors across open-source libraries — this error's family across 41 libraries.

Related errors

• Invalid configured model
• invalid model id for `model_context_windows`
• .model_context_windows. must be greater than 0
• agent profile provider cannot be empty
• agent profile provider must be a simple provider id

AI-assisted analysis of Hmbown/CodeWhale@73e0f67d83 (2026-09-22). Data as JSON: /api/errors/9745a74aa8ff9079. Report an issue: GitHub.

Appendix: source

Thrown at crates/tui/src/fleet/task_spec.rs:289

    if trimmed != value || !trimmed.chars().all(is_worker_token_char) {
        bail!(
            "fleet task {task_id} {field} must be a simple token, not a path or provider/model id"
        );
    }
    Ok(())
}

fn is_worker_token_char(ch: char) -> bool {
    ch.is_ascii_alphanumeric() || matches!(ch, '-' | '_' | '.')
}

fn validate_worker_model(task_id: &str, value: Option<&str>) -> Result<()> {
    let Some(value) = value else {
        return Ok(());
    };
    let trimmed = value.trim();
    if trimmed.is_empty() {
        bail!("fleet task {task_id} worker.model cannot be empty");
    }
    if trimmed != value
        || !trimmed
            .chars()
            .all(|ch| ch.is_ascii_graphic() && !matches!(ch, '=' | '\'' | '"'))
    {
        bail!(
            "fleet task {task_id} worker.model must be a visible model id without whitespace or secrets"
        );
    }
    Ok(())
}

#[allow(clippy::too_many_arguments)]
pub fn write_fleet_artifact_ref(
    workspace: &Path,
    run_id: &FleetRunId,
    task_id: &str,

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