sansan0/TrendRadar · error · InvalidParameterError

platforms 参数必须是列表类型

Error message

platforms 参数必须是列表类型

What it means

Raised by the platforms validator when, after the string-parsing path, the value is still not a list. The function accepts None (uses config defaults), a JSON-array string like "[\"weibo\"]" (parsed via _parse_string_to_list), or an actual list; any other type (dict, int, bare non-JSON string) reaches this raise.

Source

Thrown at mcp_server/utils/validators.py:235

        - platforms=None 时，返回 config.yaml 中配置的平台列表
        - 会验证平台ID是否在 config.yaml 的 platforms 配置中
        - 配置加载失败时，允许所有平台通过（降级策略）
    """
    supported_platforms = get_supported_platforms()

    if platforms is None:
        # 返回配置文件中的平台列表（用户的默认配置）
        return supported_platforms if supported_platforms else []

    # 支持字符串形式的列表输入（某些 MCP 客户端会将 JSON 数组序列化为字符串）
    if isinstance(platforms, str):
        platforms = _parse_string_to_list(platforms)
        if not platforms:
            # 空字符串或解析后为空，使用默认平台
            return supported_platforms if supported_platforms else []

    if not isinstance(platforms, list):
        raise InvalidParameterError("platforms 参数必须是列表类型")

    if not platforms:
        # 空列表时，返回配置文件中的平台列表
        return supported_platforms if supported_platforms else []

    # 如果配置加载失败（supported_platforms为空），允许所有平台通过
    if not supported_platforms:
        print("警告：平台配置未加载，跳过平台验证")
        return platforms

    # 验证每个平台是否在配置中
    invalid_platforms = [p for p in platforms if p not in supported_platforms]
    if invalid_platforms:
        raise InvalidParameterError(
            f"不支持的平台: {', '.join(invalid_platforms)}",
            suggestion=f"支持的平台（来自config.yaml）: {', '.join(supported_platforms)}"
        )

View on GitHub (pinned to 8ee26026ba)

Solutions

1. Pass an actual JSON array: ["weibo", "wechat"]
2. If forced to send a string, use JSON array syntax: "[\"weibo\", \"wechat\"]"
3. Omit the parameter entirely (null) to use the configured default platform list
4. Verify your MCP client is not flattening array parameters before transport

Example fix

// before
{"platforms": "weibo"}
// after
{"platforms": ["weibo"]}

if (typeof platforms === 'string') {
  try { platforms = JSON.parse(platforms); } catch { /* not JSON */ }
}
if (!Array.isArray(platforms)) platforms = undefined; // let server use defaults

function isPlatformList(v: unknown): v is string[] {
  if (typeof v === 'string') {
    try { return Array.isArray(JSON.parse(v)); } catch { return false; }
  }
  return Array.isArray(v) && v.every(p => typeof p === 'string');
}

try { call({ platforms }); }
catch (e) {
  if (/platforms 参数必须是列表类型/.test(e.message)) call({ platforms: undefined });
  else throw e;
}

When it happens

Trigger: Passing platforms as a single bare string "weibo" (not JSON-array syntax), a number, or an object like {"platform": "weibo"}. Example: tools/call with {"platforms": "weibo, wechat"} — commas without brackets are not JSON, and if _parse_string_to_list returns a non-list this raise fires.

Common situations: MCP clients that collapse arrays into concatenated strings; users writing a comma-separated list instead of a JSON array; client SDKs sending query-string style values.

Related errors

• INVALID_PARAMETER
• 无法识别的日期表达式: {expression}
• 不支持的平台: {', '.join(invalid_platforms)}
• keyword 长度不能超过100个字符
• mode 必须是字符串类型

AI-assisted analysis of sansan0/TrendRadar@8ee26026ba (2026-08-15). Data as JSON: /api/errors/a07b93ec15ec8254. Report an issue: GitHub.