HKUDS/nanobot · error · ValueError

Only a single user message is supported

Error message

Only a single user message is supported

What it means

Error "Only a single user message is supported" thrown in HKUDS/nanobot.

Source

Thrown at nanobot/api/server.py:184

                "finish_reason": finish_reason,
            }
        ],
    }
    return f"data: {_json.dumps(payload)}\n\n".encode()


_SSE_DONE = b"data: [DONE]\n\n"

# ---------------------------------------------------------------------------
# Upload helpers
# ---------------------------------------------------------------------------


def _parse_json_content(body: dict[str, Any]) -> tuple[str, list[str]]:
    """Parse JSON request body. Returns (text, media_paths)."""
    messages_value = cast(object, body.get("messages"))
    if not isinstance(messages_value, list):
        raise ValueError("Only a single user message is supported")
    messages = cast(list[object], messages_value)
    if len(messages) != 1:
        raise ValueError("Only a single user message is supported")
    message_value: object = messages[0]
    if not isinstance(message_value, dict):
        raise ValueError("Only a single user message is supported")
    message = cast(dict[str, Any], message_value)
    if message.get("role") != "user":
        raise ValueError("Only a single user message is supported")

    user_content = message.get("content", "")
    media_dir = get_media_dir("api")
    media_paths: list[str] = []

    if isinstance(user_content, list):
        text_parts: list[str] = []
        for part_value in cast(list[object], user_content):
            if not isinstance(part_value, dict):

View on GitHub (pinned to 42f37dc4c0)

When it happens

Trigger: Thrown at nanobot/api/server.py:184 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of HKUDS/nanobot@42f37dc4c0 (2026-08-26). Data as JSON: /api/errors/56de65323b143f38. Report an issue: GitHub.