Anthropic models fail on empty directories

[alexdredmon]

When running with an anthropic model in an empty directory, the follow error is emitted:

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LiteLLM.Info: If you need to debug this error, use `litellm.set_verbose=True'.

An error occurred: litellm.BadRequestError: AnthropicException - {"type":"error","error":{"type":"invalid_request_error","message":"messages: text content blocks must be non-empty"}}

This error does not occur with the same prompt in the same directory with openai

Tested using anthropic/claude-3-5-sonnet-20240620 and openai/gpt-4o