message: Add comment about API
  Summary: add comment about API
diff: @@ -116,6 +116,11 @@ read our guide to [guide to contributing](CONTRIBUTING.md)
  ## License
  `mvfst` is MIT licensed, as found in the LICENSE file.
  +## API
  +The API should be considered in alpha. We can't predict all the use cases that
  +people will have, so we're waiting some time before declaring a more stable API.
  +We are open to have several different APIs for different constraints.
  +
  ## Reporting and Fixing Security Issues
  Please do not open GitHub issues or pull requests - this makes the problem
  