nautechsystems/nautilus_trader · error

Failed to build amend order params: {e}

Error message

Failed to build amend order params: {e}

What it means

The amend-order flow builds a Kraken `AmendOrderParams` via a builder with validation. If the combination of fields (order id, quantity, price, trigger price, etc.) is invalid per the builder's checks, `build()` fails and the adapter wraps it in this anyhow error before any HTTP call is made.

Source

Thrown at crates/adapters/kraken/src/http/spot/client.rs:2909

        } else if let Some(ref id) = cl_ord_id {
            builder.cl_ord_id(id.clone());
        }

        if let Some(qty) = quantity {
            builder.order_qty(qty.to_string());
        }

        if let Some(p) = price {
            builder.limit_price(p.to_string());
        }

        if let Some(tp) = trigger_price {
            builder.trigger_price(tp.to_string());
        }

        let params = builder
            .build()
            .map_err(|e| anyhow::anyhow!("Failed to build amend order params: {e}"))?;

        let _response = self.inner.amend_order(&params).await?;

        // AmendOrder modifies in-place, so the order keeps its original ID
        let order_id = venue_order_id.ok_or(KrakenModifyOrderError::MissingOrderId)?;

        Ok(order_id)
    }

    /// Cancels an order on the Kraken Spot exchange.
    ///
    /// # Errors
    ///
    /// Returns an error if:
    /// - Credentials are missing.
    /// - Neither client_order_id nor venue_order_id is provided.
    /// - The request fails.
    /// - The order cancellation is rejected.

View on GitHub (pinned to 18893faf8b)

Solutions

1. Read the inner `{e}` message; it names the exact builder validation that failed.
2. Ensure exactly one valid order identifier is supplied and it is non-empty.
3. Validate quantity/price/trigger-price values are positive and correctly formatted before calling amend.
4. Use values sourced from the original order report (precision-correct Price/Quantity types converted with `to_string()`).

Example fix

// before
builder.quantity("0"); // invalid qty
// after
builder.quantity(order.quantity().to_string());

fn validate_amend(venue_order_id: Option<&str>, qty: Option<Decimal>, price: Option<Decimal>) -> Result<(), String> {
    if venue_order_id.map_or(true, |s| s.is_empty()) {
        return Err("amend requires non-empty venue order id".into());
    }
    if qty.map_or(false, |q| q <= Decimal::ZERO) { return Err("amend qty must be positive".into()); }
    if price.map_or(false, |p| p <= Decimal::ZERO) { return Err("amend price must be positive".into()); }
    Ok(())
}

match client.amend_order(req).await {
    Ok(r) => r,
    Err(e) if e.to_string().contains("Failed to build amend order params") => {
        log::error!("invalid amend request {:?}: {e}", req);
        return Err(e);
    }
    Err(e) => return Err(e),
}

When it happens

Trigger: Calling amend-order with an invalid parameter combination: e.g. both a modify quantity and price that violate builder invariants, empty required identifiers, malformed price/quantity strings, or mutually exclusive fields set together.

Common situations: Strategy code amending an order with a computed price that formats to an invalid string (NaN/zero precision); passing both `venue_order_id` and client order id in a way the builder rejects; amend requests constructed from partially-filled order state with invalid sizes.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

• Failed to build cancel params: {e}
• Failed to build order params: {e}
• limit_price is required for batch order type {order_type:?}
• Conditional order type {order_type:?} requires trigger_price
• Leverage {n}:1 not supported for {raw_symbol} on {side_label

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/25b08809ffc5e25e. Report an issue: GitHub.