microsoft/autogen · error · InvalidOperationException

Expected Input to be specified

Error message

Expected Input to be specified

What it means

Error "Expected Input to be specified" thrown in microsoft/autogen.

Source

Thrown at dotnet/src/AutoGen.Anthropic/Middleware/AnthropicMessageConnector.cs:65

            }
            else
            {
                yield return reply;
            }
        }
    }

    private IMessage? ProcessChatCompletionResponse(IMessage<ChatCompletionResponse> chatMessage,
        IStreamingAgent agent)
    {
        if (chatMessage.Content.Content is { Count: 1 } &&
            chatMessage.Content.Content[0] is ToolUseContent toolUseContent)
        {
            return new ToolCallMessage(
                toolUseContent.Name ??
                throw new InvalidOperationException($"Expected {nameof(toolUseContent.Name)} to be specified"),
                toolUseContent.Input?.ToString() ??
                throw new InvalidOperationException($"Expected {nameof(toolUseContent.Input)} to be specified"),
                from: agent.Name);
        }

        var delta = chatMessage.Content.Delta;
        return delta != null && !string.IsNullOrEmpty(delta.Text)
            ? new TextMessageUpdate(role: Role.Assistant, delta.Text, from: agent.Name)
            : null;
    }

    private async Task<IEnumerable<IMessage>> ProcessMessageAsync(IEnumerable<IMessage> messages, IAgent agent)
    {
        var processedMessages = new List<IMessage>();

        foreach (var message in messages)
        {
            var processedMessage = message switch
            {
                TextMessage textMessage => ProcessTextMessage(textMessage, agent),

View on GitHub (pinned to 027ecf0a37)

Solutions

1. Provide an input object (even an empty dict) for every tool_use block

Example fix

Set input={} or the parsed arguments dict on the tool_use block

When it happens

Trigger: Thrown at dotnet/src/AutoGen.Anthropic/Middleware/AnthropicMessageConnector.cs:65 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of microsoft/autogen@027ecf0a37 (2026-08-15). Data as JSON: /api/errors/6636a72a3a707a82. Report an issue: GitHub.