deepseek-ai/deepseek-harness · error · AttachmentError

UNSUPPORTED_IMAGE_TYPE

UNSUPPORTED_IMAGE_TYPE

Error message

Image type ${input.mediaType} is not accepted by this deployment.

What it means

Error "Image type ${input.mediaType} is not accepted by this deployment." thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/attachment/attachment/src/index.ts:72

   * Validate one ordered image batch before committing any member.
   * Validation failures start no writes; storage failures return no partial
   * references, although already published content-addressed objects may stay
   * unreachable until a future retention policy collects them.
   * @param inputs - encoded images in their owning message order.
   * @returns durable references in the exact input order.
   */
  protected validateImageBatch(inputs: readonly SaveImageAttachment[]): void {
    const { maxImagesPerMessage, maxMessageImageBytes, mediaTypes } = this.imageLimits
    if (inputs.length > maxImagesPerMessage) {
      throw new AttachmentError('Image batch exceeds the configured image-count limit.', 'TOO_MANY_IMAGES')
    }
    const totalBytes = inputs.reduce((sum, input) => sum + input.data.byteLength, 0)
    if (totalBytes > maxMessageImageBytes) {
      throw new AttachmentError('Image batch exceeds the configured aggregate image-byte limit.', 'IMAGES_TOO_LARGE')
    }
    for (const input of inputs) {
      if (!mediaTypes.includes(input.mediaType)) {
        throw new AttachmentError(`Image type ${input.mediaType} is not accepted by this deployment.`, 'UNSUPPORTED_IMAGE_TYPE')
      }
    }
  }

  /**
   * Validate and durably commit one ordered image batch.
   * @param inputs - encoded images in owning-message order.
   * @returns durable normalized attachment references in the same order after every member succeeds.
   */
  async saveImages(inputs: readonly SaveImageAttachment[]): Promise<readonly ImageAttachmentRef[]> {
    this.validateImageBatch(inputs)
    for (const input of inputs) await this.validateImage(input)

    const refs: ImageAttachmentRef[] = []
    for (const input of inputs) refs.push(await this.saveImage(input))
    return refs
  }

View on GitHub (pinned to b150a551b8)

Solutions

1. Convert the image to an accepted type or add the type to the deployment accepted list.

When it happens

Trigger: Thrown at packages/attachment/attachment/src/index.ts:72 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of deepseek-ai/deepseek-harness@b150a551b8 (2026-08-24). Data as JSON: /api/errors/8423cd6c60025c16. Report an issue: GitHub.