nautechsystems/nautilus_trader · error · anyhow::Error

Gamma {scope} filter '{key}' values must be unsigned integer

Error message

Gamma {scope} filter '{key}' values must be unsigned integers: {e}

What it means

parse_gamma_numeric_filter_list first splits a comma-separated Gamma filter into a list (parse_gamma_filter_list) then parses each element as u64. If any individual element fails u64 parsing, the whole filter fails with 'Gamma {scope} filter {key} values must be unsigned integers'.

Source

Thrown at crates/adapters/polymarket/src/providers.rs:1018

        .map(str::to_string)
        .collect::<Vec<_>>();

    if values.is_empty() || values.iter().any(String::is_empty) {
        anyhow::bail!("Gamma {scope} filter '{key}' must contain non-empty comma-separated values")
    }
    Ok(values)
}

fn parse_gamma_numeric_filter_list(
    scope: &str,
    key: &str,
    value: &str,
) -> anyhow::Result<Vec<u64>> {
    parse_gamma_filter_list(scope, key, value)?
        .into_iter()
        .map(|item| {
            item.parse::<u64>().map_err(|e| {
                anyhow::anyhow!(
                    "Gamma {scope} filter '{key}' values must be unsigned integers: {e}"
                )
            })
        })
        .collect()
}

fn parse_gamma_filter_string(scope: &str, key: &str, value: &str) -> anyhow::Result<String> {
    if value.trim().is_empty() {
        anyhow::bail!("Gamma {scope} filter '{key}' cannot be empty")
    }
    Ok(value.to_string())
}

/// Resolves a tag slug to a tag ID by querying the Gamma tags endpoint.
pub async fn resolve_tag_slug(
    client: &PolymarketGammaHttpClient,
    slug: &str,

View on GitHub (pinned to 18893faf8b)

Solutions

1. Ensure every comma-separated element is a bare non-negative integer, e.g. "1,2,3"
2. Remove empty segments caused by trailing commas; trim whitespace around each item (the parser trims only after splitting)
3. Validate the list in the caller with a parse::<u64> check before building params
4. If a mixed-type list is needed, use the non-numeric list filter variant instead

Example fix

// before
filters.insert("tag_ids", "12, 34,");
// after
filters.insert("tag_ids", "12,34");

// Rust
fn is_u64_list(v: &str) -> bool {
    v.split(',').map(str::trim).all(|s| s.parse::<u64>().is_ok())
}

When it happens

Trigger: Passing a comma-separated list filter where at least one element is not a plain non-negative integer, e.g. "123, abc" or "1, 2.5, 3".

Common situations: Lists built by joining IDs with names, trailing commas producing empty elements, or list values accidentally nested/quoted in config.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• Gamma {scope} filter '{key}' must be an unsigned integer: {e
• fee exponent must be non-negative
• Gamma {scope} filter '{key}' must be a decimal number: {e}
• unrecognized side '{side}'
• quantity size={} cannot be represented with precision={}

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/96f7c39a4ec67ffe. Report an issue: GitHub.