bionicjs
Concepts

The RPC Boundary

The typed contract between TypeScript and Python. Call a Python function like a local one - serialization, transport, and types are generated for you.

Communication

TypeScript and Python communicate through a generated typed RPC boundary. The TypeScript server calls Python functions as if they were local — the serialization, transport, and deserialization are automatic.

Generation

The RPC stubs are generated at build time from your Python function signatures. Types flow from Python to TypeScript — no manual type definitions needed.

from bionicjs import ai

async def chat(message: str) -> str:
    """Send a message to the AI."""
    client = ai.client()
    response = await client.chat.completions.create(
        model="claude-sonnet-4-5",
        messages=[{"role": "user", "content": message}],
    )
    return response.choices[0].message.content

This generates a TypeScript client:

import { chat } from "@bionicjs/core/server/ai";

const reply = await chat("Hello!"); // typed as (message: string) => Promise<string>

The contract

The contract is the function signature. Python defines the types, TypeScript consumes them. If the Python signature changes, the TypeScript types update on the next build. No schema files, no manual sync.

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