Indian citizen applying for Chinese tourist visa in Hong Kong.

Based on the current information, you are able to try to apply it in HK through a local tour agency, but it is not assured that you can get it in the end.

No matter whether you can get approved or not, you need to prepare your valid passport, an application form with a recent taken letter, round trip tickets to China, hotel booking, a personal statement and your proof of legal status in HK.

For other documents, you still need to consult with the different tour agencies. Applying in HK is not so easy as you thought and it may not be easier than applying in your country. Personally speaking, you are suggested to apply in your country if you are still in India.