Alternatives
Products that do what JSONing Mock API does
Free and open source fake API for testing and prototyping
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Free mock api generator for developers | instant test data
Nov 2025 · fakeapifordevs.vercel.app
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2023 · jsongenerator.io
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Hi HN, I built the first version of Mocktail years ago. I recently came back to the project, and after a pretty substantial rebuild, v4 is now out. Mocktail is a free and open-source, self-hosted mock API server with a built-in dashboard and database, packaged as a single ~25 MB binary. You can run it locally or on your own infrastructure — no account or hosted service required. You can define endpoints and responses, generate realistic data per request, customize headers, status codes and latency, and inspect incoming requests in real time. With v4, I also added MCP support, so coding…
23d ago · getmocktail.com
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Hey there HN! I just wrapped up an all-day documentation spree for Instant API, a JavaScript framework for easily building web APIs that implements type safety at the HTTP interface. It uses a function-as-a-service approach combined with a slightly modified JSDoc spec to automatically enforce parameter and schema validation before HTTP requests make it through to your code. You just write comments above your endpoint functions and voila, enforced type safety contracts between your API endpoints and your developers. OpenAPI specifications are generated automatically as a byproduct of simply…
2023 · github.com
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Hey HN, we’re building an open specification that lets agents discover and invoke APIs with natural language, built on the OpenAPI standard. agents.json clearly defines the contract between LLMs and API as a standard that's open, observable, and replicable. Here’s a walkthrough of how it works: https://youtu.be/kby2Wdt2Dtk?si=59xGCDy48Zzwr7ND. There’s 2 parts to this: 1. An agents.json file describes how to link API calls together into outcome-based tools for LLMs. This file sits alongside an OpenAPI file. 2. The agents.json SDK loads agents.json files as tools for an LLM that…
2025 · github.com
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2021 · github.com
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2019 · mockit.netlify.com
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2024 · fooapi.com
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Hi HN! I'm Ankit, the founder of Beeceptor, a request mocking and intercepting tool. This time, I built something new to address a pain I’ve personally felt (and heard from dozens of QA, frontend, and platform teams): making OpenAPI specs actually useful during development. API contracts just sit around as docs often. What if you could 'activate' them, instantly have a realistic, hosted mock server-with contract validation, smart test data, and early usage? So I made _Mockaroo for OpenAPI_, but with brains. It spins up a hosted mock server from your spec in one click. It: - Generates…
2025 · beeceptor.com
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