@llm4ts/core

Effect-native LLM contracts: backend-neutral messages, responses, streaming chunks, usage, health, structured output, tools, evaluation, and the connector registry. This is the foundation package of llm4ts.

Install

npm install @llm4ts/core effect

Requires Node.js >= 22. effect is a peer dependency pinned to the Effect 4 beta line.

Usage

The package exposes explicit subpath exports — import the module you need:

import { LlmServiceShape } from "@llm4ts/core/LlmService"
import { Message, LlmResponse, ConnectorIds } from "@llm4ts/core/Models"
import { ApiConnectorConfig } from "@llm4ts/core/ConnectorConfig"
import { collect } from "@llm4ts/core/Streaming"

Connectors for OpenAI, Anthropic, Gemini, LM Studio, Ollama, and CLI coding agents (Claude, Codex, Gemini CLI, and more) live under @llm4ts/core/providers/*. A deterministic mock connector (@llm4ts/core/providers/MockProvider) works with zero configuration and no credentials.

Most applications should start from @llm4ts/runner (Node composition and flows) or @llm4ts/js (Promise-based facade) rather than wiring core services directly.

Documentation

• Repository and full documentation
• API overview
• Provider capabilities

License

MIT