AI · alternatives · 2026
24 alternatives to Open sourcing Restly – GPT-4 powered tutorials from your OpenAPI spec
Hi HN - Marius (mbuleandra) and I built Restly as a side project. Restly generates a user-friendly tutorial against any OpenAPI spec. While building public-facing APIs, we found that writing these guides by hand took a lot of work. Many OpenAPI specs were too large to send to GPT-4 / Claude directly, and even when we could send them, we experienced lost-in-the-middle and hallucination issues. The project is very alpha but works against the Vocode API when we specify well-defined goals. Let us know your thoughts; we would love your contribution to the project! [1]…
Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Open sourcing Restly – GPT-4 powered tutorials from your OpenAPI spec launched in 2023; newer entries below may have overtaken it.
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Generate custom data & API to build apps in less than 30s
2021 · retool.com · its alternatives →
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Generate customized, realistic mock data & APIs, via GPT
2023 · its alternatives →
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Fern▲260We built the world’s first generated, idiomatic gRPC and REST SDK. If you have public gRPC and REST endpoints, Fern is the SDK provider for you.
2025 · buildwithfern.com · its alternatives →
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2023 · openapistack.co · its alternatives →
- 6TA
An OpenAPI alternative to describe REST APIs for type-safe code generation.
2023 · typeapi.org · its alternatives →
- 7WM
Try it out! https://glhf.chat/ Hey HN! We’ve been working for the past few months on a website to let you easily run (almost) any open-source LLM on autoscaling GPU clusters. It’s free for now while we figure out how to price it, but we expect to be cheaper than most GPU offerings since we can run the models multi-tenant. Unlike Together AI, Fireworks, etc, we’ll run any model that the open-source vLLM project supports: we don’t have a hardcoded list. If you want a specific model or finetune, you don’t have to ask us for it: you can just paste the Hugging Face link in and…
2024 · glhf.chat · its alternatives →
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SingleAPI▲209Convert the internet into your own API using GPT
2023 · singleapi.co · its alternatives →
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Generate and share OpenAPI specs with AI
2025 · api.dev · its alternatives →
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Instantly generate openapi (OAS) 3.0.0 REST + GraphQL APIs
2019 · github.com · its alternatives →
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GPT-500▲95500+ new & unique side projects people built using GPT-4
2023 · pr1ncesingh.gumroad.com · its alternatives →
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Hey hacker news, we launched a few weeks ago as a GPT-powered chatbot for developer docs, and quickly realized that the value of what we’re doing isn’t the chatbot itself. Rather, it’s the time we save developers by automating the extraction of data from their SaaS tools (Github, Zendesk, Salesforce, etc) and helping transform it to contextually relevant chunks that fit into GPT’s context window. A lot of companies are building prototypes with GPT right now and they’re all using some combination of Langchain/Llama Index + Weaviate/Pinecone + GPT3.5/GPT4 as their stack for…
2023 · github.com · its alternatives →
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Hey HN, We just shipped a new AI-powered feature... BUT the "AI" piece is largely in the background. Instead of relying on a chatbot, we've integrated AI (with strict input & output guardrails) into a workflow to handle two specific tasks that would be difficult for traditional programming: 1. Identifying the most relevant base URL from HAR files, since it would be tedious to cover every edge case or scenario to omit analytics, tracking, and other network noise. 2. Generating synthetic data for API requests by passing the API context and faker-js functions to GPT-4. The steps are broken down…
2024 · docs.multiple.dev · its alternatives →
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I’ve been working on an open-source CLI tool called Dochia for a while now. The reason for building it: in microservices architectures, testing is repetitive: every service exposes APIs, and much of the testing process will share a similar set of test cases: negative inputs, boundary cases, encoding quirks, invisible characters. I wanted a tool that could automate this shared layer of testing instead of doing it manually across dozens of services. So what Dochia does: reads your OpenAPI spec; generates thousands of smart, edge-case payloads automatically and produces detailed reports with…
2025 · github.com · its alternatives →
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A generator for OpenAPI 3. Contribute to egorsmkv/openapi3-generator development by creating an account on GitHub.
2020 · github.com · its alternatives →
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Hi everyone, We built a quick experiment this weekend that allows you to use GPT4 to quickly generate shareable web apps that use the ChatGPT API. Here’s a video of me building an app similar to https://whatdoesthiscodedo.com/: https://www.youtube.com/watch?v=VpvGd21V0u0 "What does this code do?" went to #1 on Hacker News a couple of months ago. The app takes a piece of code, asks GPT4 to analyze it and returns a simple, English description of the code. An app like this is super simple to build with MetaGPT. What other kinds of things can you build with this? *…
2023 · picoapps.xyz · its alternatives →
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Build a REST API on top of your data warehouse. Contribute to mjirv/demeter development by creating an account on GitHub.
2022 · github.com · its alternatives →
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Hi HN! We’re excited to share our new code generator that lets you ship high-quality TypeScript SDKs, that your users will love, from your OpenAPI documents. Our ongoing goal is to help you build one SDK that runs anywhere modern JavaScript runs. This includes new runtimes like Deno and Bun in addition to the ever-popular Node.js. Additionally, the popularity of AI has meant server-sent events and file streaming are also commonplace - we wanted to cover these use cases too. This explosion in new runtimes and ways of interacting with APIs shifts cognitive burden on API developers often having…
2024 · speakeasyapi.dev · its alternatives →
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Hi Hacker News! Patrick and Elias here. We built an SDK / Documentation generator for REST APIs. The link included shows the shiny output of our system: the docs! We generated 5 SDKs and docs from the Hacker News OpenAPI we found on GitHub. If you write code in Python, Typescript, Go, Ruby, or Rust, we’d love for you to try an SDK out! If you want to generate SDKs for your own API try our tool here: https://github.com/Sideko-Inc/sideko We are both software engineers, and we built this tool because we were spending too much time writing API integrations, supporting…
2023 · hacker-news.sideko.dev · its alternatives →
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Easily collect all transcriptions from a YouTube channel to create your own custom GPT (via OpenAI) or querying a large context window (Claude 2.1) The example is “CY GPT” your very own Sichael Miebel and Calton Daldwell in your pocket. I have a backlog of open-source projects, hope this helps!! This is counter intuitive (as I’m posting this) but please respect the creators copyright and use for research purposes only
2023 · github.com · its alternatives →
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OpenAPI linting, diffing and testing. Optic helps prevent breaking changes, publish accurate documentation and improve the design of your APIs. - optic/docs/generate-openapi.md at main · opticdev/optic
2023 · github.com · its alternatives →
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We built an open-source tool that scans your codebase and generates OpenAPI docs in minutes. Right now it supports Rails, Go, Python, and NodeJS frameworks, and we will keep adding more. It picks up routes, params, request bodies, and models directly from the code and outputs a clean OpenAPI spec you can drop into your workflow.
Nov 2025 · github.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 →