How to manually create a tf.Summary()

You can create a tf.Summary object in your Python program and write it to the same tf.summary.FileWriter object that takes your TensorFlow-produced summaries using the SummaryWriter.add_summary() method.

The tf.Summary class is a Python protocol buffer wrapper for the Summary protocol buffer. Each Summary contains a list of tf.Summary.Value protocol buffers, which each have a tag and a either a “simple” (floating-point scalar) value, an image, a histogram, or an audio snippet. For example, you can generate a scalar summary from a Python object as follows:

writer = tf.train.SummaryWriter(...)
value = 37.0
summary = tf.Summary(value=[
    tf.Summary.Value(tag="summary_tag", simple_value=value), 
])
writer.add_summary(summary)