Pyright is a fast type checker meant for large Python source bases. It can run in a “watch” mode and performs fast incremental updates when files are modified.
Pyright supports [configuration files](configuration.md) that provide granular control over settings. Different “execution environments” can be associated with subdirectories within a source base. Each environment can specify different module search paths, python language versions, and platform targets.
* Intelligent type completion of keywords, symbols, and import names appears when editing
* Import statements are automatically inserted when necessary for type completions
* Signature completion tips help when filling in arguments for a call
* Hover over symbols to provide type information and doc strings
* Find Definitions to quickly go to the location of a symbol’s definition
* Find References to find all references to a symbol within a code base
* Rename Symbol to rename all references to a symbol within a code base
* Find Symbols within the current document or within the entire workspace
* View call hierarchy information — calls made within a function and places where a function is called
* Organize Imports command for automatically ordering imports according to PEP8 rules
* Type stub generation for third-party libraries
### Built-in Type Stubs
Pyright includes a recent copy of the stdlib type stubs from [Typeshed](https://github.com/python/typeshed). It can be configured to use another (perhaps more recent or modified) copy of the Typeshed type stubs. Of course, it also works with custom type stub files that are part of your project.
## Limitations
Pyright provides support for Python 3.0 and newer. There are no plans to support older versions.