Open Source AI Coding Tools
Open Source AI coding tools, editors, agents, and MCP servers — 72 curated.
Agno
A Python framework for building multi-agent systems with memory, knowledge, and tools — formerly Phidata, now with the AgentOS runtime.
Aider
Open-source terminal AI pair programmer that edits files in your Git repo and auto-commits each change, working with Claude, GPT, and other models you bring.
Arize Phoenix
An open-source LLM observability and evaluation tool built on OpenTelemetry, runnable anywhere.
AutoGen (AG2)
A multi-agent conversation framework where agents collaborate via message-passing, with group chat and code execution.
BAML
A domain-specific language for type-safe LLM functions, with generated clients and schema-aligned parsing.
Browser Use
The most-adopted open-source browser-agent framework — point an LLM at a task and it drives a real browser: navigating, clicking, typing, extracting.
Chonkie
A lightweight, fast chunking library for RAG with many splitting strategies in one API.
Chroma
An open-source, Python-first vector database that runs in-process — the fastest path from pip install to a working retrieval prototype.
Chrome DevTools MCP
Google's official MCP server that gives coding agents a live Chrome — Puppeteer automation plus DevTools network, console, and performance insights.
Cline
Open-source autonomous coding agent for VS Code that plans, edits files, and runs commands with diff approval, using any model you bring or a local runtime.
Codex CLI
OpenAI's open-source terminal coding agent with sandboxed execution and two-layer approval controls.
Continue
An open-source IDE extension for building custom AI coding assistants.
CrewAI
A Python framework for orchestrating role-playing AI agents as collaborating 'crews', plus event-driven flows.
DeepEval
An open-source evaluation framework for LLM apps — 'Pytest for LLMs' with ready-made metrics and CI integration.
Docling
Open-source Python library that parses PDFs, DOCX, PPTX, HTML, and images into structured Markdown and JSON with layout, tables, and reading order for RAG.
DSPy
Program language models instead of prompting them: declare tasks as typed signatures and let optimizers compile the prompts and few-shot examples for you.
FastMCP
A Pythonic framework for building Model Context Protocol servers and clients — decorator-based tools, resources, and prompts, with auth and deployment built in.
Flowise
Open-source, low-code visual builder for LLM apps and AI agents — drag-and-drop to assemble chains, agents, and RAG; self-host or use Flowise Cloud.
Gemini CLI
Google's open-source terminal AI agent powered by Gemini models, with a 1M-token context window and built-in tools.
Github MCP Server
GitHub's official MCP server — repos, issues, PRs, Actions, and security data for your agent, as a free hosted remote or a local Docker server.
Google ADK
Google's open-source, code-first framework to build, evaluate, and deploy AI agents. Python and Java, model-agnostic, deploys to Vertex AI Agent Engine.
Goose
Block's open-source, on-machine AI agent that is MCP-native and model-agnostic, with a CLI and desktop app.
Helicone
Open-source LLM observability and AI gateway with one-line integration — logging, tracing, caching, and cost/latency tracking across providers.
Instructor
Get structured, validated output from LLMs using plain type definitions, with automatic retries on validation failure.
Jan
An open-source ChatGPT alternative that runs fully offline — a polished desktop app over llama.cpp with a model hub, MCP support, and a local API server.
LanceDB
An open-source embedded vector database built on the Lance columnar format — serverless, multimodal, and designed to scale on local disk or object storage.
Langchain
The provider-agnostic agent framework, post-1.0: a standard create_agent loop on the LangGraph runtime, middleware hooks, and the largest integration ecosystem.
Langfuse
An open-source LLM engineering platform for tracing, evals, prompt management, and metrics.
LangGraph
A low-level library for building stateful, controllable agents as graphs, with checkpointing and human-in-the-loop.
LiteLLM
Call 100+ LLM APIs with one OpenAI-format interface — as a Python library or a self-hosted gateway/proxy.
Llama Cpp
The C/C++ inference engine that made local LLMs possible — GGUF quantization, every GPU backend, and an OpenAI-compatible server, with no dependencies.
Llamaindex
The data framework for LLM apps — ingestion, indexing, query engines, and document agents — now centered on document processing with LlamaParse and LlamaCloud.
LLM Guard
An open-source security toolkit of input and output scanners for LLM apps — prompt injection, PII/anonymize, secrets, toxicity, and more, from Protect AI.
Marker
Open-source pipeline that converts PDFs, images, and Office docs into clean Markdown, JSON, or HTML fast, with optional LLM assist for tables and equations.
Mastra
An open-source TypeScript framework for building AI agents, workflows, RAG, and tool-calling, with memory, model routing, and built-in observability.
MCP Inspector
The official open-source visual tool for testing and debugging Model Context Protocol servers — connect, list, and call tools, resources, and prompts.
Mem0
A memory layer for AI agents and apps — persistent, personalized long-term memory across sessions.
Milvus
An open-source vector database built for billion-scale similarity search, with a distributed architecture and a wide menu of index types.
NeMo Guardrails
NVIDIA's open-source toolkit for adding programmable guardrails to LLM apps — input, dialog, retrieval, and output rails defined in the Colang language.
Ollama
An open-source tool to run open-weight LLMs locally with a single command, including a local OpenAI-compatible API.
OpenAI Agents SDK
OpenAI's lightweight, open-source framework for agents — handoffs, guardrails, sessions, and built-in tracing.
Opencode
The open-source AI coding agent — a terminal TUI from Anomaly with 75+ model providers, LSP-powered context, parallel agents, and shareable sessions.
OpenHands
Open-source autonomous AI software-development agent (formerly OpenDevin) — writes code, runs commands, and browses the web in a sandbox.
pgroll
An open-source CLI for zero-downtime, reversible Postgres schema migrations using the expand-contract pattern behind versioned schema views.
pgvector
An open-source Postgres extension that adds a vector type and HNSW/IVFFlat indexes for similarity search inside your existing database.
Pipecat
An open-source Python framework for real-time voice and multimodal conversational AI — it orchestrates streaming STT, LLM, and TTS into composable pipelines.
Playwright MCP
Microsoft's open-source MCP server that gives AI agents structured browser automation via Playwright's accessibility tree.
Postgres MCP Pro
The maintained Postgres MCP server — safe SQL execution, EXPLAIN with hypothetical indexes, workload-driven index tuning, and database health checks.
promptfoo
An open-source CLI for testing, comparing, and red-teaming LLM prompts, models, and apps.
Pydantic AI
Type-safe agent framework from the Pydantic team: validated structured outputs, dependency injection, durable execution, 'that FastAPI feeling.'
Qdrant
An open-source vector database written in Rust, built for low-latency similarity search at scale.
Qwen3-VL
Alibaba Qwen's open-weights vision-language model family (2B–235B, Apache-2.0): image and document understanding, OCR, visual reasoning, and video.
RAGAS
An open-source framework for evaluating retrieval-augmented generation with reference-free RAG metrics.
Roo Code
A discontinued open-source VS Code agent (a Cline fork); the team has since pivoted away from the IDE extension.
Sequential Thinking MCP
The official MCP reference server for structured reasoning — a sequential_thinking tool that lets agents decompose, revise, and branch their thinking.
Serena
An MCP toolkit that gives coding agents IDE-grade powers — symbol-level retrieval and editing via language servers, across 40+ languages.
Skyvern
Open-source vision + LLM browser automation aimed at replacing brittle RPA — workflow builder, CAPTCHA/2FA handling, and self-host or cloud.
Slack MCP Server
The community-canonical Slack MCP server — smart history fetch, message search, channels, reactions, and opt-in posting, after the official server was archived.
Spec Kit
GitHub's open-source toolkit for spec-driven development — a specify CLI and /speckit slash commands that walk any coding agent from spec to implementation.
Stagehand
Browserbase's open-source SDK for browser agents — act, extract, observe, and agent primitives that mix natural language with code-level control.
Supabase MCP
Supabase's official MCP server — run SQL and migrations, read logs and advisors, generate types, and deploy Edge Functions, with read-only and project scoping.
Swe Agent
Open-source autonomous coding agent from Princeton/Stanford that turns an LLM into a software engineer to fix real GitHub issues.
Tabby
Self-hosted, open-source AI coding assistant by TabbyML — run your own completion and chat models on your infrastructure, with IDE extensions.
Unsloth
An open-source library that makes LoRA/QLoRA fine-tuning of LLMs roughly 2x faster and far more memory-efficient, so you can fine-tune on a single GPU.
Vercel AI SDK
An open-source TypeScript toolkit for building AI apps — unified model API, streaming, structured output, tool calling, and UI hooks.
vLLM
A high-throughput, memory-efficient inference and serving engine for LLMs, with PagedAttention, continuous batching, and an OpenAI-compatible API server.
Void — Open-Source AI Code Editor (VS Code Fork)
Open-source AI code editor forked from VS Code, an alternative to Cursor that connects directly to your chosen model with no proprietary backend.
Warp
A modern, AI-powered terminal with an agent mode that can run and chain commands across your codebase.
Wave Terminal
Open-source terminal that blends the CLI with inline file previews, a built-in editor, a web browser, and a context-aware AI assistant in one window.
Weaviate
An open-source vector database with built-in hybrid search, pluggable vectorizer modules, and GraphQL/REST/gRPC APIs.
Whisper
OpenAI's open-weights speech-to-text — the MIT-licensed multilingual model family that made self-hosted transcription a default, with a huge ecosystem.