wavetermdev/waveterm · error

value at index %d is not a number

Error message

value at index %d is not a number

What it means

During summation each element of valuesSlice is asserted to float64 (the type encoding/json produces for any JSON number). Any element that isn't a plain number (string, bool, nested array/object, null) aborts with the offending index. The float is truncated to int before accumulation.

Source

Thrown at pkg/aiusechat/tools.go:310

			valuesInterface, ok := inputMap["values"]
			if !ok {
				return nil, fmt.Errorf("missing values parameter")
			}

			valuesSlice, ok := valuesInterface.([]any)
			if !ok {
				return nil, fmt.Errorf("values must be an array")
			}

			if len(valuesSlice) == 0 {
				return 0, nil
			}

			sum := 0
			for i, val := range valuesSlice {
				floatVal, ok := val.(float64)
				if !ok {
					return nil, fmt.Errorf("value at index %d is not a number", i)
				}
				sum += int(floatVal)
			}

			return sum, nil
		},
	}
}

View on GitHub (pinned to a4447c1563)

Solutions

1. Send only numeric JSON values in the array: {"values": [1, 2, 3]} — unquoted, no nulls
2. If numbers may arrive as strings, preprocess/coerce them (parseFloat / strconv) before calling, or wrap the tool with a coercing shim
3. Note truncation: the tool int-truncates floats; pre-round client-side if rounding behavior matters

Example fix

// before
anySum({"values": [1, "2", 3]})
// after
anySum({"values": [1, 2, 3]})

for i, v := range values { if _, ok := v.(float64); !ok { return fmt.Errorf("element %d not a number", i) } }

func allNumbers(s []any) bool { for _, v := range s { if _, ok := v.(float64); !ok { return false } }; return true }

out, err := tool.Call(input); if err != nil && strings.Contains(err.Error(), "is not a number") { return sanitizeAndRetry(err) }

When it happens

Trigger: Tool called with a mixed array such as {"values": [1, "two", 3]}, {"values": [1, null, 3]}, or {"values": [[1],[2]]} — element at index i fails the float64 assertion.

Common situations: Model emitting quoted numbers ("5" instead of 5); strings embedded for units ("3px"); nulls representing missing data; nested arrays the model intended to flatten.

Related errors

• values must be an array
• invalid input format
• invalid input format: %w
• Invalid path part: ${pathPart}
• convertFileUIMessagePart expects 'file' type, got '%s'

AI-assisted analysis of wavetermdev/waveterm@a4447c1563 (2026-09-01). Data as JSON: /api/errors/3b2ff170745673d5. Report an issue: GitHub.