sigoden/aichat · error

Invalid value

Error message

Invalid value '{}'

What it means

Thrown by the generic parse_value::<T>() helper (src/config/mod.rs:2695) when a string value fails T::from_str. It is used to parse environment-variable overrides and similar string inputs into typed config values; the literal string "null" maps to None, everything else must parse. The message echoes the offending raw string.

Solutions

1. Correct the env var / input value to a format the target type parses (numbers unquoted, bools as true/false).
2. Use the literal string "null" to unset an override instead of an empty or invalid value.
3. Check the type of the config field being overridden and match it exactly.

Example fix

// before
export AICHAT_TEMPERATURE=high
// after
export AICHAT_TEMPERATURE=0.7

fn is_parsable_int(s: &str) -> bool { s.parse::<i64>().is_ok() } // apply per target type before export

fn as_f64_env(key: &str) -> Option<f64> { std::env::var(key).ok().and_then(|v| v.trim().parse().ok()) }

match parse_value::<f64>(&raw) { Ok(v) => v, Err(e) => { eprintln!("{e}; expected a number"); return Ok(()); } }

When it happens

Trigger: Setting an env override (e.g. AICHAT_* variables or mapped config env keys) whose value cannot be parsed into the target type — e.g. a non-numeric string where a number, a non-boolean where a bool (`true`/`false`), or a malformed value for an enum/URL type.

Common situations: Exporting AICHAT_TEMPERATURE=high instead of 0.7; AICHAT_MAX_TOKENS with units ("4k") instead of a plain integer; whitespace or quotes accidentally included in the env value.

Understand the failure class

Background: "is not a valid" / "Invalid ... value" environment variable errors: how libraries validate env vars and what to do when they reject yours — this error's family across 48 libraries.

AI-assisted analysis of sigoden/aichat@82976d349a (2026-09-09). Data as JSON: /api/errors/18632b082ae04bc8. Report an issue: GitHub.

Appendix: source

Thrown at src/config/mod.rs:2695

fn read_env_value<T>(key: &str) -> Option<Option<T>>
where
    T: std::str::FromStr,
{
    let value = env::var(key).ok()?;
    let value = parse_value(&value).ok()?;
    Some(value)
}

fn parse_value<T>(value: &str) -> Result<Option<T>>
where
    T: std::str::FromStr,
{
    let value = if value == "null" {
        None
    } else {
        let value = match value.parse() {
            Ok(value) => value,
            Err(_) => bail!("Invalid value '{}'", value),
        };
        Some(value)
    };
    Ok(value)
}

fn read_env_bool(key: &str) -> Option<Option<bool>> {
    let value = env::var(key).ok()?;
    Some(parse_bool(&value))
}

fn complete_bool(value: bool) -> Vec<String> {
    vec![(!value).to_string()]
}

fn complete_option_bool(value: Option<bool>) -> Vec<String> {
    match value {
        Some(true) => vec!["false".to_string(), "null".to_string()],

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