HeyPuter/puter · error · HttpError

bad_request

bad_request

Error message

`prompt` must be a non-empty string

What it means

CloudflareImageProvider.generate requires a prompt that is a string and non-empty after trim; anything else (undefined, number, empty, whitespace-only) throws HTTP 400 bad_request before doing any work or spending credits.

Source

Thrown at src/backend/drivers/ai-image/providers/cloudflare/CloudflareImageProvider.ts:97

        return CLOUDFLARE_IMAGE_GENERATION_MODELS;
    }

    getDefaultModel(): string {
        return DEFAULT_MODEL;
    }

    async generate(params: IGenerateParams): Promise<string> {
        const options = params as CloudflareGenerateParams;
        const { prompt, test_mode } = options;
        const ratio = this.#normalizeRatio(options.ratio);
        const selectedModel = this.#getModel(options.model);

        if (test_mode) {
            return 'https://puter-sample-data.puter.site/image_example.png';
        }

        if (typeof prompt !== 'string' || prompt.trim().length === 0) {
            throw new HttpError(400, '`prompt` must be a non-empty string', {
                legacyCode: 'bad_request',
            });
        }

        const actor = Context.get('actor');
        if (!actor) {
            throw new HttpError(401, 'actor not found in context', {
                legacyCode: 'unauthorized',
            });
        }

        // Canonical `input_images`/`input_image` → Cloudflare's `image` field.
        // Cloudflare accepts a single input image; a URL is fetched to base64
        // server-side (SSRF-guarded) since the API has no URL field.
        const singleInput = resolveSingleInputImage(options, 'Cloudflare');
        if (singleInput) {
            options.image ??= isHttpUrl(singleInput)
                ? (await fetchImageAsBase64(singleInput)).base64

View on GitHub (pinned to 908ec23eda)

Solutions

1. Ensure prompt is a non-empty trimmed string before calling generate().
2. Disable the submit UI until a prompt is entered.
3. Type-check/guard prompt at the call site.

Example fix

// before
await provider.generate({ prompt: '' });
// after
if (typeof prompt !== 'string' || prompt.trim().length === 0) throw new Error('prompt required');
await provider.generate({ prompt });

if (typeof prompt !== 'string' || prompt.trim().length === 0) {
  throw new Error('prompt must be a non-empty string');
}

function isNonEmptyPrompt(p) {
  return typeof p === 'string' && p.trim().length > 0;
}

When it happens

Trigger: Calling Cloudflare image generation with no prompt, an empty prompt, or a non-string prompt (e.g. passing an object or number by mistake).

Common situations: UI submitting before the user typed a prompt; variable not initialized; prompt built from an empty template field.

Related errors

• bad_request
• cannot_write_to_root
• bad_request
• bad_request
• bad_request

AI-assisted analysis of HeyPuter/puter@908ec23eda (2026-08-12). Data as JSON: /api/errors/520ada0320ff5b82. Report an issue: GitHub.