deepseek-ai/deepseek-harness · error · LlmError

UNSUPPORTED_CONTENT

UNSUPPORTED_CONTENT

Error message

pi-ai chat history cannot represent structured assistant image output

What it means

Error "pi-ai chat history cannot represent structured assistant image output" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/llm/llm-pi-ai/src/replay.ts:158

  }
}

/** Convert provider-neutral blocks without trusting them as same-model replay. */
function foreignAssistant(message: Message): AssistantMessage {
  const source = message.source.kind === 'model' ? message.source : undefined
  const content: AssistantMessage['content'] = []
  for (const block of message.content) {
    switch (block.type) {
      case 'text': content.push({ type: 'text', text: block.text }); break
      case 'reasoning': content.push({ type: 'thinking', thinking: block.text }); break
      case 'tool-call': content.push({
        type: 'toolCall',
        id: block.id,
        name: block.name,
        arguments: parseArguments(block.arguments),
      }); break
      case 'image':
        throw new LlmError('pi-ai chat history cannot represent structured assistant image output', 'UNSUPPORTED_CONTENT')
      default:
        // plugin-added block types are not representable in pi-ai.
        break
    }
  }
  return {
    role: 'assistant',
    content,
    // Deliberately never equals a catalog API: absent replay state is foreign
    // even if source names the same provider/model as this request.
    api: 'dsh-foreign',
    provider: source?.provider ?? 'dsh-foreign',
    model: source?.model ?? 'dsh-foreign',
    usage: emptyPiUsage(),
    stopReason: content.some(piece => piece.type === 'toolCall') ? 'toolUse' : 'stop',
    timestamp: 0,
  }
}

View on GitHub (pinned to b150a551b8)

Solutions

1. Remove structured assistant image output from the chat history before replay.

When it happens

Trigger: Thrown at packages/llm/llm-pi-ai/src/replay.ts:158 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/dff9df7343c8ab3b. Report an issue: GitHub.