agent '{name}' cannot set both `keep_alive` and `keep_alive_

Error message

agent '{name}' cannot set both `keep_alive` and `keep_alive_on_failure`

What it means

launchd agents support either keep_alive (restart always) or keep_alive_on_failure (restart only on non-zero exit), but not both simultaneously, since their semantics conflict. from_toml enforces this mutual exclusion when parsing the agent config. The user must pick one keep-alive strategy.

Source

Thrown at src/system/launchd.rs:121

    pub request: LaunchdRequest,
    pub path: PathBuf,
    pub loaded: bool,
    pub state: LaunchdState,
}

impl LaunchdRequest {
    pub(crate) fn from_toml(name: String, config: LaunchdTomlConfig) -> Result<Self> {
        if !valid_name(&name) {
            bail!("agent name '{name}' must contain only letters, numbers, '.', '_', or '-'");
        }
        let Some(program) = config.program.map(|s| s.trim().to_string()) else {
            bail!("agent '{name}' must set `program`");
        };
        if program.is_empty() {
            bail!("agent '{name}' must set a non-empty `program`");
        }
        if config.keep_alive && config.keep_alive_on_failure {
            bail!("agent '{name}' cannot set both `keep_alive` and `keep_alive_on_failure`");
        }
        if config.nice.is_some_and(|nice| !(-20..=20).contains(&nice)) {
            bail!("agent '{name}' `nice` must be between -20 and 20");
        }
        if let Some(interval) = &config.start_calendar_interval {
            interval.validate(&name)?;
        }
        for dir in &config.queue_directories {
            if dir.trim().is_empty() {
                bail!("agent '{name}' `queue_directories` must not contain empty entries");
            }
            // checked against the raw string rather than `Path::is_absolute` on the
            // expanded value: the plist is consumed by macOS launchd, so POSIX rules
            // apply regardless of the platform parsing the config, and on Windows
            // `Path::new("/var/spool").is_absolute()` is false (root, but no prefix)
            if !is_absolute_launchd_path(dir) {
                bail!(
                    "agent '{name}' `queue_directories` entry '{dir}' must be an absolute path \

View on GitHub (pinned to afd2eddd3a)

Solutions

Keep only keep_alive = true if the agent should always be running
Keep only keep_alive_on_failure = true if the agent should restart solely after failures
Remove the boolean you do not want from the agent's TOML section

Example fix

// before
[launchd.my-agent]
keep_alive = true
keep_alive_on_failure = true
// after
[launchd.my-agent]
keep_alive_on_failure = true

Defensive patterns

Strategy: validation

Validate before calling

let keep_alive = cfg.get("keep_alive").and_then(|v| v.as_bool()).unwrap_or(false);
let on_failure = cfg.get("keep_alive_on_failure").and_then(|v| v.as_bool()).unwrap_or(false);
if keep_alive && on_failure {
    anyhow::bail!("choose either keep_alive or keep_alive_on_failure, not both");
}

Prevention

Pick one restart policy per agent and document it
When merging configs, drop one of the two keys explicitly
Default to keep_alive_on_failure for crash-only services

When it happens

Trigger: Setting both keep_alive = true and keep_alive_on_failure = true on the same [launchd.<name>] agent section.

Common situations: Merging two agent configs (one using each option) during refactoring; copy-pasting keep_alive from an example while also enabling keep_alive_on_failure for crash-only restarts; experimenting with both restart modes.

Related errors

AI-assisted analysis of jdx/mise@afd2eddd3a (2026-09-09). Data as JSON: /api/errors/6c2d911fcc340057. Report an issue: GitHub.