linshenkx/prompt-optimizer · error · VariableExtractionParseError

variables[${index}] is missing a valid "name" field.

Error message

variables[${index}] is missing a valid "name" field.

What it means

The variables array entry at ${index} is an object but its 'name' field is missing, not a string, or a blank/whitespace-only string. A non-empty name is required for every extracted variable, so normalization aborts at this entry.

Source

Thrown at packages/core/src/services/variable-extraction/service.ts:215

    // 验证 variables 字段
    if (!Array.isArray(data.variables)) {
      throw new VariableExtractionParseError('Extraction result must have a "variables" array.');
    }

    // 验证 summary 字段
    if (typeof data.summary !== 'string') {
      throw new VariableExtractionParseError('Extraction result must have a "summary" string.');
    }

    // 标准化每个变量
    const variables: ExtractedVariable[] = data.variables.map((variable: any, index: number) => {
      // 验证必需字段
      if (!variable || typeof variable !== 'object') {
        throw new VariableExtractionParseError(`variables[${index}] is not a valid object.`);
      }

      if (typeof variable.name !== 'string' || !variable.name.trim()) {
        throw new VariableExtractionParseError(`variables[${index}] is missing a valid "name" field.`);
      }

      if (typeof variable.value !== 'string') {
        throw new VariableExtractionParseError(`variables[${index}] is missing a valid "value" field.`);
      }

      if (!variable.position || typeof variable.position !== 'object') {
        throw new VariableExtractionParseError(`variables[${index}] is missing a valid "position" object.`);
      }

      if (typeof variable.position.originalText !== 'string') {
        throw new VariableExtractionParseError(
          `variables[${index}].position is missing a valid "originalText" field.`
        );
      }

      if (typeof variable.position.occurrence !== 'number') {
        throw new VariableExtractionParseError(

View on GitHub (pinned to 3e677b1d9f)

Solutions

1. Log the failing entry to see which key the model used instead of 'name'.
2. Add a shim mapping common alternates: v.name ?? v.key ?? v.variable.
3. Fix the prompt/template to require "name" as a non-empty string with a few-shot example.
4. Filter out nameless entries before calling extraction if they are noise.

Example fix

// before
return this.normalizeExtractionResponse(parsed);

// after
parsed.variables = parsed.variables.map(v => ({ ...v, name: v.name ?? v.key ?? v.variable })).filter(v => typeof v.name === 'string' && v.name.trim());
return this.normalizeExtractionResponse(parsed);

const hasValidName = (v: unknown): v is { name: string; [k: string]: unknown } =>
  !!v && typeof v === 'object' && typeof (v as any).name === 'string' && (v as any).name.trim().length > 0;

try {
  await extractionService.extract({ modelKey, content });
} catch (e) {
  if (e instanceof VariableExtractionParseError && /"name" field/.test(e.message)) {
    // remap alternate keys (key/variable) and filter empty names, then retry
  }
  throw e;
}

When it happens

Trigger: The model returns a variable object where name is undefined, null, a number, or ''/' '. Reached via extract() during per-variable validation in normalizeExtractionResponse.

Common situations: Model uses a different key ('key', 'variable', 'id') instead of 'name'; model returns empty-string names for hallucinated slots; multilingual model returning name with only whitespace; schema drift after template edits.

Related errors

• variables[${index}] is not a valid object.
• variables[${index}] is missing a valid "value" field.
• Extraction result must have a "variables" array.
• Extraction result must have a "summary" string.
• Invalid import data format

AI-assisted analysis of linshenkx/prompt-optimizer@3e677b1d9f (2026-08-27). Data as JSON: /api/errors/a56adf24ef983dda. Report an issue: GitHub.