alibaba/spring-ai-alibaba · error · BizException

INVALID_PARAMS

INVALID_PARAMS

Error message

expected type is ${type} but not match the current value type.

What it means

VariableUtils.convertValueByType converts a raw variable value (string/JSON) into the declared target type. When conversion fails — bad JSON, wrong shape, incompatible value — the catch block (or the fall-through) throws BizException with code INVALID_PARAMS naming the expected type.

Source

Thrown at spring-ai-alibaba-admin/spring-ai-alibaba-admin-server-core/src/main/java/com/alibaba/cloud/ai/studio/core/utils/common/VariableUtils.java:323

			else if (ParameterTypeEnum.ARRAY_BOOLEAN.getCode().equals(type)) {
				if (value instanceof List) {
					return value;
				}
				else if (value instanceof String) {
					return JsonUtils.fromJsonToList((String) value, Boolean.class);
				}
			}
			else if (ParameterTypeEnum.ARRAY_FILE.getCode().equals(type)) {
				if (value instanceof List) {
					return value;
				}
				else if (value instanceof String) {
					return JsonUtils.fromJsonToList((String) value, File.class);
				}
			}
		}
		catch (Exception e) {
			throw new BizException(ErrorCode.INVALID_PARAMS.toError(key,
					"expected type is " + type + " but not match the current value type."));
		}
		throw new BizException(ErrorCode.INVALID_PARAMS.toError(key,
				"expected type is " + type + " but not match the current value type."));
	}

	/**
	 * Identifies variables from text content (ordered, non-unique)
	 */
	public static List<String> identifyVariableListFromText(String content) {
		List<String> result = Lists.newArrayList();
		if (StringUtils.isBlank(content)) {
			return result;
		}
		Matcher matcher = VAR_EXPR_PATTERN.matcher(content);
		// 查找并添加匹配的内容
		while (matcher.find()) {
			result.add(matcher.group(1));

View on GitHub (pinned to f82da0b50f)

Solutions

1. Log/inspect the actual value and the declared type; fix the value to match the expected type
2. Validate/parse the value with JsonUtils before assignment to catch malformed JSON early
3. Correct the variable's declared type to match the real data shape
4. Wrap the call site in a try-catch for BizException and surface a user-friendly message identifying the offending key

Example fix

// before
Object v = VariableUtils.convertValueByType("ids", "List", "not-json");
// after
String raw = "[\"a\",\"b\"]";
if (!JsonUtils.isJsonArray(raw)) {
    throw new IllegalArgumentException("ids must be a JSON array");
}
Object v = VariableUtils.convertValueByType("ids", "List", raw);

boolean canConvert(String type, Object value) {
    try {
        VariableUtils.convertValueByType("__probe__", type, value);
        return true;
    } catch (Exception e) {
        return false;
    }
}

boolean isJsonString(Object v) { return v instanceof String s && (s.startsWith("{") || s.startsWith("[")); }

try {
    Object v = VariableUtils.convertValueByType(key, type, value);
} catch (BizException e) {
    if (ErrorCode.INVALID_PARAMS.name().equals(e.getCode())) {
        log.warn("Variable {} cannot be converted to {}: {}", key, type, value);
    }
}

When it happens

Trigger: Calling convertValueByType with a value that cannot be converted to the requested type: non-JSON string for a list/object target, numeric string for a non-numeric type, malformed File JSON for File targets, or null/unconvertible input reaching the final throw.

Common situations: Workflow variable substitution where upstream node output type differs from declared variable type; users typing values in admin UI forms that don't match configured types; JSON stored with extra quoting or truncation.

Understand the failure class

Background: Type mismatch errors: IllegalArgumentException, TypeError and type guards across 150 open-source libraries — this error's family across 150 libraries.

Related errors

• INVALID_PARAMS
• INVALID_PARAMS
• failed to parse Long type: {}
• 变量替换失败，使用原始模板: template={}, variables={}

AI-assisted analysis of alibaba/spring-ai-alibaba@f82da0b50f (2026-09-09). Data as JSON: /api/errors/3d9263043e5f723d. Report an issue: GitHub.