linshenkx/prompt-optimizer · critical · EvaluationExecutionError

Image storage service is required to resolve evaluation imag

Error message

Image storage service is required to resolve evaluation image asset "${assetId}".

What it means

EvaluationExecutionError thrown by resolveEvaluationMediaItem when an evidence item has an assetId but EvaluationService was constructed without an imageStorageService. Resolving stored assets requires that service; without it the asset reference cannot be dereferenced, so multimodal execution aborts.

Source

Thrown at packages/core/src/services/evaluation/service.ts:857

    const label = mediaItem.label?.trim() || 'image';
    const inlineB64 = mediaItem.b64?.trim() || '';
    const assetId = mediaItem.assetId?.trim() || '';

    if (inlineB64) {
      return {
        b64: inlineB64,
        mimeType: mediaItem.mimeType?.trim() || 'image/png',
      };
    }

    if (!assetId) {
      throw new EvaluationExecutionError(
        `Evaluation image evidence "${label}" is missing both assetId and b64 data.`
      );
    }

    if (!this.imageStorageService) {
      throw new EvaluationExecutionError(
        `Image storage service is required to resolve evaluation image asset "${assetId}".`
      );
    }

    const storedImage = await this.imageStorageService.getImage(assetId);
    if (!storedImage?.data?.trim()) {
      throw new EvaluationExecutionError(
        `Failed to resolve evaluation image asset "${assetId}".`
      );
    }

    return {
      b64: storedImage.data,
      mimeType: mediaItem.mimeType?.trim() || storedImage.metadata?.mimeType || 'image/png',
    };
  }

  private buildEvaluationMediaIdentity(mediaItem: EvaluationMediaItem): string {

View on GitHub (pinned to 3e677b1d9f)

Solutions

1. Provide an imageStorageService when constructing EvaluationService whenever assets may be referenced by id
2. Alternatively, embed images inline as b64 evidence so no storage service is needed
3. Add a startup/diagnostic check: if any configured mode is image-based, require imageStorageService

Example fix

// before
const svc = new EvaluationService({ modelManager, templateManager, llmService, imageUnderstandingService });

// after
const svc = new EvaluationService({
  modelManager, templateManager, llmService, imageUnderstandingService,
  imageStorageService,
});

const usesAssets = evidence.some(e => Boolean(e.assetId) && !e.b64);
if (usesAssets && !imageStorageService) throw new Error('assetId evidence requires imageStorageService');

const serviceSupportsAssets = (svc: EvaluationService) => Boolean((svc as any).imageStorageService);

try { await svc.evaluate(req); } catch (e) { if (e instanceof EvaluationExecutionError && /Image storage service/.test(e.message)) { inlineB64EvidenceAndRetry(); } else throw e; }

When it happens

Trigger: Evidence items reference stored images by assetId while EvaluationService lacks imageStorageService in its constructor options — common in unit tests or minimal DI setups — and an image-mode evaluation runs.

Common situations: DI composition updated for text-only usage and image storage omitted; test harness constructing the service with mocks but no image store; refactor dropped an optional constructor parameter; deployment profile that disabled image persistence.

Related errors

• Image understanding service is not available for multimodal
• Image result evaluation requires at least one output image e
• Image compare evaluation requires at least two snapshots wit
• Image compare evaluation requires every compared snapshot to
• No valid image evidence could be resolved for evaluation.

AI-assisted analysis of linshenkx/prompt-optimizer@3e677b1d9f (2026-08-27). Data as JSON: /api/errors/462860c44f6a2355. Report an issue: GitHub.