SDK
Client libraries in 23 languages, from TypeScript and Go to Rust, Elixir, and Lean. You call entities and operations rather than URLs, and retry, caching, and tracing are generated features you switch on.
Open source SDKs for API-first SaaS
One OpenAPI spec becomes six surfaces: an SDK, a CLI, an MCP Server, Agent Skills, a REPL, and a Semantic Model. Change the spec and the generator rewrites all six from one model, so they cannot drift apart.
What you get from one spec#
Voxgig reads your OpenAPI spec into a type-safe model of your API: the entities, their attributes, and the operations on them. Every surface below is generated from that one model, so a change to the spec reaches all six on the next run.
CLI
A command-line tool over the same entities, for scripts and on-call work: myapi load myentity rather than a URL path and a request body.
MCP Server
A Model Context Protocol server, so an agent such as Claude, Cursor, or Cline calls your API as a native tool.
Agent Skills
Generated markdown that teaches a coding agent your entities and operations, so the calls it writes in chat use them rather than guessed URLs.
REPL
An interactive shell over the same entities, for trying a call and reading the result before you write it into code.
Semantic Model
The type-safe model of your API: its entities, their attributes, and the operations on them. The other five surfaces are generated from it, and your own tooling can be built on it directly.
Why this exists#
The SDK maintenance tax
Your first customer wants Go. The next wants Python. Now you own N SDKs, and every API change is N updates, N test suites, and N migrations you have to talk customers through.
The agent-experience shift
AI agents are already calling your API, and they want an MCP server. Hand-roll one and it drifts from your SDK the day you ship the next release.
If you build it, you own it
It does not matter who wrote the code: an engineer, an AI assistant, or a generator. The SDK sits in your repository and you carry the maintenance. The tool changes who types, not who owns.
More than endpoint wrappers#
The mechanical half is the endpoints
Any generator can wrap your paths in typed methods. The time goes into the rest: retries that back off, idempotency keys that survive a retry, a cache that does not serve a body somebody already read, and pagination that knows when to stop. You write that by hand, once per language, forever.
So the generator writes that too
Twenty opt-in features ship with it: retry with backoff, timeouts, rate limiting, caching, idempotency keys, pagination, streaming, tracing, metrics, audit records, cost tracking, a debug buffer, client tracking, role-based access checks, proxy routing, credential resolution, payload validation, logging, an offline mock transport, and network simulation. Each is implemented in every language the generator targets, and each is off until you switch it on. Read what each feature does. When the stock output is not enough, you customize without forking: your own features, and even your own language targets.
Why Voxgig generates from a model#
Whoever writes the SDK, you own it
Hand-written, AI-assisted, or generated, it makes no difference. Once the code is in your repository you maintain it, which is why what a generator writes matters more than how fast it writes it.
Deterministic generation, from a type-safe model
Voxgig extracts your API as entities, their attributes, and the operations on them, then generates from that model and nothing else. The same spec produces the same model and the same six surfaces on every run. You think in entities and operations rather than in URL paths and JSON schemas.
Teams Voxgig has worked with
Three ways to work with Voxgig#
1. Adopt the open source
Generate your SDKs, CLI, MCP Server, Agent Skills, REPL, and Semantic Model from your spec. The generator is MIT licensed, and there is no sales call to sit through.
Read the generator documentationBrowse the open source2. Hire Voxgig for Developer Experience
Take the generated SDKs the rest of the way: idiomatic in each language, tested, documented, and released through a pipeline your team runs.
See the Developer Experience service3. Hire Voxgig for Agent Experience
Ship an MCP server your customers' AI agents can use, generated from the same spec as your SDK so the two cannot disagree.
See the Agent Experience servicestarts you on the open source. No sign-up is needed.
600+
SDKs already generated, at github.com/voxgig-sdk
23 languages
From TypeScript and Go to Rust, Elixir, and Lean
MIT licensed
The generator and the SDKs it writes are yours to keep
Since 2018
Voxgig Ltd., Dublin and Brentford
Voxgig also runs the Fireside podcast#
Since 2018, conversations with the people building developer relations, developer tooling, and developer communities. Every episode is searchable by guest, topic, and season.