AI · alternatives · 2026
24 alternatives to An Open Source Version of OpenAI Assistants API
i built an open source version of OpenAI Assistants API it's compatible with any LLM & embeddings model and u can swap it out for OpenAI assistants API with just one line of code. if you want this let me know 👇
Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Prices are shown for the 1 we have checked on their own sites, 1 of them free or with a free tier. An Open Source Version of OpenAI Assistants API launched in 2023; newer entries below may have overtaken it.
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Hi everyone, we’re a small team, supported by Mozilla, who are working on re-imagining a UI for training, tuning and testing local LLMs. Everything is open source. If you’ve been training your own LLMs or have always wanted to, we’d love for you to play with the tool and give feedback on what the future development experience for LLM engineering could look like.
2025 · github.com · its alternatives →
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Hey everyone, We have been building SecureAI Tools -- an open-source application layer for ChatGPT and ChatPDF-like AI tools. It works with locally running LLMs as well as with OpenAI-compatible APIs. For local LLMs, it supports Ollama which supports all the gguf/ggml models. Currently, it has two features: Chat-with-LLM, and Chat-with-PDFs. It is optimized for self-hosting use cases and comes with basic user management features. Here are some quick demos: * Chat with documents using OpenAI's GPT3.5 model: https://www.youtube.com/watch?v=Br2D3G9O47s * Chat with documents…
2023 · github.com · its alternatives →
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OpenAI o1 API ▲458OpenAI's most advanced model, o1 API to third-party devs
2024 · developers.openai.com · its alternatives →
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We built SwiftAI, an open-source Swift library that lets you use Apple’s on-device LLMs when available (Apple opened access in June), and fall back to a cloud model when they aren’t available — all without duplicating code. SwiftAI gives you: - A single, model-agnostic API - An agent/tool loop - Strongly-typed structured outputs - Optional chat state Backstory: We started experimenting with Apple’s local models because they’re free (no API calls), private, and work offline. The problem: not all devices support them (older iPhones, Apple Intelligence disabled, low battery, etc.). That…
2025 · github.com · its alternatives →
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LLM Gatewayfree tier▲296I built an OpenAI-compatible LLM gateway that routes requests to OpenAI, Anthropic, Ollama, vLLM, llama-server, SGLang... anything that speaks /v1/chat/completions. Single Go binary, one YAML config file, no infrastructure. It does the things you'd expect from this kind of gateway... semantic routing via a three-layer cascade (keyword heuristics, embedding similarity, LLM classifier) that picks the best model when clients omit the model field, weighted round-robin load balancing across local inference servers with health checks and failover. The part I think is most…
2025 · llmgateway.io · its alternatives →
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Hey HN, I am proud to show you guys that I have built an open source alternative to Azure OpenAI services. Azure OpenAI services was born out of companies needing enhanced security and access control for using different GPT models. I want to build an OSS version of Azure OpenAI services that people could self host in their own infrastructure. "How can I track LLM spend per API key?" "Can I create a development OpenAI API key with limited access for Bob?" "Can I see my LLM spend breakdown by models and endpoints?" "Can I create 100 OpenAI API keys that my students could use in a classroom…
2023 · github.com · its alternatives →
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Agnes AI ▲124Hi HN, I'm Daniel, part of the team at Agnes AI, a Singapore-based AI lab. We've been building quietly for a while and I wanted to share what we've made with this community and get honest feedback from people who actually build things. What is Agnes AI? Agnes AI gives you access to three models through a single free API. We have text, image and video models. The API is fully OpenAI-compatible, so you can just swap the base URL to https://apihub.agnes-ai.com/v1 and use your Agnes API key. No other changes needed in your existing code. It is completely free. No need to submit…
2025 · agnes-ai.com · its alternatives →
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traceAI▲273Open-source LLM tracing that speaks GenAI, not HTTP.
Apr 2026 · github.com · its alternatives →
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Hey HN, I’ve built Open Codex, a fully local, open-source alternative to OpenAI’s Codex CLI. My initial plan was to fork their project and extend it. I even started doing that. But it turned out their code has several leaky abstractions, which made it hard to override core behavior cleanly. Shortly after, OpenAI introduced breaking changes. Maintaining my customizations on top became increasingly difficult. So I rewrote the whole thing from scratch using Python. My version is designed to support local LLMs. Right now, it only works with phi-4-mini (GGUF) via…
2025 · github.com · its alternatives →
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Bring reliable AI virtual assistants to your app
2024 · scoopika.com · its alternatives →
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Free AI with your ChatGPT account. Contribute to EvanZhouDev/openai-oauth development by creating an account on GitHub.
Mar 2026 · github.com · its alternatives →
- 13

ChatGPT-like customer interactions in a website widget
2024 · openwidget.com · its alternatives →
- 14

Self-hosted alternative to OpenAI's Responses API compatible with Agents SDK and works with all model providers (Claude/R1/Qwen/Ollama etc) - open-responses/open-responses
2025 · github.com · its alternatives →
- 15
OpenAI Cookbook▲135Examples and guides for using the OpenAI API
2023 · github.com · its alternatives →
- 16

Proxy remote LLM API as Ollama and LM Studio, for using them in JetBrains AI Assistant - Stream29/ProxyAsLocalModel
2025 · github.com · its alternatives →
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The official Slack AI product looks great, but with limited access and add-on pricing, I decided to open-source the version I built. Especially for all the communities on Slack that would have to convert to paid and buy the upgrade to access the official SlackAI product/add-on which is not going to be financially viable in most cases. There's no plan to sell anything, just something I built as a way to learn some new tools that I thought others might get use out of. The repo is a ready-to-run slack app that provides thread summaries and channel overviews on demand using OpenAI (heavy…
2024 · github.com · its alternatives →
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Provides the same proxy OpenAI API for different LLM models
2024 · github.com · its alternatives →
- 21

api2ai parses OpenAPI Spec to generate an agent that can make API calls. For context, I recently need to explore a handful of API suites and thought LLMs can help expedite this process. After some digging, I found OpenAPI Specs are perfect fit for function calling. Based on a text prompt, api2ai can select the right endpoint and properly parse request params and make api calls. It also handles authentication, currently it supports basic auth, api keys, and bearer token schemes. The tool has helped me explore and see APIs in action without a deep dive into the docs or using postman. It’s open…
2023 · github.com · its alternatives →
- 22

Hi, I'm working on a project that regroups all best AI (AIaaS) from different providers (GCP, AWS, Azure, DeepL, etc.) in one API (https://github.com/edenai/edenai-apis). I've got asked the question : why aren't you regrouping Open Source models (instead of proprietary APIs) into one repo? Well because it doesn't make sens to deploy and maintain large pytorch (or other framework) AI models (especially for document parsing, image and video moderation or speech recognition) in every solution that wants AI capabilities. So using APIs makes way more sens. Deployed OpenSource…
2023 · github.com · its alternatives →
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Rispose.com▲20Hey, OpenAI recently released "assistants" - These have RAG built into the API, which means that you can provide up to 10.000 files to the assistant without the overhead of dealing with vector databases, splitting files into chunks and more. They work surprisingly well, so I've built a free simple tool to embed them on websites. It has no dependencies and simply uses fetch to communicate to my backend which proxies openai. In the future I plan to add more widget embedding options (currently only chat is available). Let me know if you have any specific questions about either the tool or…
2025 · rispose.com · its alternatives →
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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →