deepseek-ai/deepseek-harness · error · Error

cannot read "${args.file_path}": ${mediaType} images are not

Error message

cannot read "${args.file_path}": ${mediaType} images are not accepted by this deployment

What it means

Error "cannot read "${args.file_path}": ${mediaType} images are not accepted by this deployment" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/fs/tool-fs/src/read-image.ts:206

    },
    // Content-addressed attachment writes are idempotent, so concurrent reads
    // of the same file cannot conflict.
    isConcurrencySafe: () => true,
    async execute(args, exec) {
      if (args.file_path.trim().length === 0) throw new Error('file_path must be a non-empty string')

      // Every gate runs before any filesystem I/O so a refusal never leaks
      // partial reads or attachment writes.
      const mediaType = imageMediaTypeForPath(args.file_path)
      if (mediaType === undefined) {
        throw new Error(`cannot read "${args.file_path}": read_image only accepts PNG/JPEG/WebP/GIF paths`)
      }
      const attachments = ctx.get('attachments')
      if (attachments === undefined) {
        throw new Error(`cannot read "${args.file_path}" as an image: no attachment service is mounted`)
      }
      if (!attachments.imageLimits.mediaTypes.includes(mediaType)) {
        throw new Error(`cannot read "${args.file_path}": ${mediaType} images are not accepted by this deployment`)
      }
      await assertImageCapableRoute(ctx, exec, args.file_path)

      const { target, info } = await resolveRegularReadTarget(ctx, exec, args.file_path)

      // The tool result is one message carrying one image, so the per-message
      // aggregate bound applies beside the per-image bound.
      const byteCap = Math.min(attachments.imageLimits.maxImageBytes, attachments.imageLimits.maxMessageImageBytes)
      const data = await ctx.fs.readBytes(target, exec.signal, byteCap)
      // Persist before returning: the image block must reference a durably
      // committed object by the time the tool/result event is appended.
      let ref: ImageAttachmentRef
      try {
        ref = await attachments.saveImage({ data, mediaType, name: basename(target.displayPath) })
      } catch (error: unknown) {
        if (!(error instanceof AttachmentError)) throw error
        // Dimension refusals stay recoverable tool errors: an oversized image
        // must never enter durable history, where it would ride every later

View on GitHub (pinned to b150a551b8)

When it happens

Trigger: Thrown at packages/fs/tool-fs/src/read-image.ts:206 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/3557be7259f45575. Report an issue: GitHub.