Brings hot module reloading and reactive programming primitives from Python's hmr library into Claude. You get tools to set up reactive dependencies, trigger updates when values change, and reload modules without restarting your session. Reach for this when you're iterating on Python code in a REPL style workflow and want automatic propagation of changes through dependent computations. Built on Pyodide, so it runs Python in WebAssembly. The reactive model lets you define cells that automatically recalculate when their inputs change, similar to how spreadsheets or Jupyter's reactive cousins work. Served over streamable HTTP from the Pythonline project's infrastructure.
claude mcp add --transport http io.github.promplate-hmr https://promplate.github.io/pyth-on-line/hmr/mcp