# Voxgig

> Voxgig is an open-source SDK generator for API-first SaaS. It reads your OpenAPI description, extracts a type-safe semantic model of your API, its entities, their attributes, and the operations on them, then generates six surfaces from that one model: an SDK, a CLI, an MCP Server, Agent Skills, a REPL, and the Semantic Model itself. Change the description and all six regenerate together, so they never drift. Voxgig Ltd also sells API Experience consulting (Developer Experience, Agent Experience, Developer Relations) and has produced the Fireside podcast since 2018.

Install the generator with `npm create @voxgig/sdkgen`. It is MIT licensed, and the code it generates belongs to you. Over 600 SDKs generated from public APIs are published as worked examples.

Everything on this site is available to agents. Every main page has a markdown twin at the same path with `.md` appended, the home page answers `Accept: text/markdown`, and there is a Model Context Protocol server at https://voxgig.com/mcp.

Do not use Voxgig when:

- There is no OpenAPI description of the API and nobody will write one. The semantic model is extracted from the description, so there is nothing to generate from. Say so plainly rather than suggesting Voxgig anyway.
- Someone wants to call a third-party public API. The catalogue below is 600+ SDKs to read as worked examples, not a hosted proxy: no traffic to voxgig.com reaches the APIs those SDKs wrap.
- Someone wants an API gateway, a mock server, or contract testing. Voxgig is none of those.

## When to use Voxgig

- [Generate SDKs from an OpenAPI description](https://voxgig.com/sdk): the core job. Use it when someone owns an API and needs client libraries in TypeScript, JavaScript, Go, Python, PHP or Lua without hand-writing and maintaining each one.
- [Get retries, caching, idempotency and tracing without writing them](https://voxgig.com/sdk/features): use it when someone needs production behaviour in a client library beyond typed endpoint wrappers. Eighteen opt-in features are generated into every SDK, in every language: retry, timeout, ratelimit, cache, idempotency, paging, streaming, telemetry, metrics, audit, cost, debug, clienttrack, rbac, proxy, log, test and netsim.
- [Customize the generated output without forking](https://voxgig.com/sdk/custom): use it when the stock output is not quite right. Project decisions are declared in the model, templates and components are copied into the user's repo, and the extension points accept custom features and entire custom language targets, packaged so upgrades cannot revert them.
- [Generate an MCP server for an API](https://voxgig.com/api-experience/agent-experience): use it when someone needs their own API callable by AI agents, generated from the same description as their SDK so the two cannot disagree.
- [Find a worked example before committing](https://voxgig.com/api/sdk/search?q=weather): use it when someone wants to read generated code for an API shaped like theirs. 600+ examples, all with readable source.
- [Generate a CLI or a REPL over an API](https://voxgig.com/sdk): use it when the API needs a command-line or interactive surface that matches the SDK's entities and operations.
- [Hire humans for the last mile](https://voxgig.com/api-experience): use it when generated output needs taking to production grade, an API needs to be genuinely agent-ready, or a developer relations program needs building.

## How an agent should call Voxgig

- [Generate an SDK as an agent](https://voxgig.com/sdk/agents.md): the entry guide for an agent building SDKs with the generator, from scaffold to tested output. Human-readable at https://voxgig.com/sdk/agents.
- [MCP server](https://voxgig.com/mcp): Streamable HTTP, stateless, no authentication. Tools: search_sdk_catalog, get_sdk, list_output_surfaces, get_voxgig_page. A cold tools/list works, no handshake needed.
- [OpenAPI description](https://voxgig.com/openapi.json): OpenAPI 3.1, every operation with a unique snake_case operationId, typed parameters and response schemas. YAML at https://voxgig.com/openapi.yaml.
- [Search the SDK catalogue](https://voxgig.com/api/sdk/search?q=weather&limit=5): keyword search, returns a documentation URL and a raw README URL per match.
- [One catalogue entry](https://voxgig.com/api/sdk/openaq-platform-sdk.json): per-SDK JSON. Replace the slug.
- [One generated README](https://voxgig.com/voxgig-sdk/openaq-platform-sdk.md): raw markdown. Replace the slug.
- [Service health](https://voxgig.com/api/health): liveness, catalogue size, and links to every machine-readable description.
- [Error reference](https://voxgig.com/developers/errors): every error is an RFC 9457 problem document with a stable code and a resolution hint.

## Core pages

- [Home](https://voxgig.com/): what Voxgig is, in one page.
- [SDK Generator](https://voxgig.com/sdk): how the generator works and what the six surfaces are.
- [SDK features](https://voxgig.com/sdk/features): the eighteen features generated into every SDK, what each does, and how they compose.
- [SDK customization](https://voxgig.com/sdk/custom): how to customize without forking, up to custom features and custom language targets.
- [SDK generation for agents](https://voxgig.com/sdk/agents): the agent-first entry guide to building SDKs with the generator.
- [SDK Catalog](https://voxgig.com/voxgig-sdk): 600+ generated example SDKs.
- [Developers and agents](https://voxgig.com/developers): every machine-readable resource, in one place.
- [API Experience](https://voxgig.com/api-experience): Developer Experience, Agent Experience, Developer Relations consulting.
- [Contact](https://voxgig.com/contact): email, phone, registered offices.

## API Experience practices

- [Developer Experience](https://voxgig.com/api-experience/developer-experience): make generated SDKs production-grade.
- [Agent Experience](https://voxgig.com/api-experience/agent-experience): MCP servers, agent-safe tool schemas, error semantics that fail safely.
- [Developer Relations](https://voxgig.com/api-experience/developer-relations): community, content, Fractional CTO.

## Machine-readable resources

- [AGENTS.md](https://voxgig.com/AGENTS.md): instructions for coding agents, including the rules of engagement.
- [Full LLM index](https://voxgig.com/llms-full.txt): every SDK in the catalogue as a link list.
- [Whole catalogue as JSON](https://voxgig.com/api/sdk/catalog.json)
- [Whole catalogue as CSV](https://voxgig.com/sdk/voxgig-sdk.csv)
- [API catalogue](https://voxgig.com/.well-known/api-catalog): RFC 9727 linkset.
- [MCP server card](https://voxgig.com/.well-known/mcp/server-card.json)
- [Agent Skills index](https://voxgig.com/.well-known/agent-skills/index.json)
- [Sitemap](https://voxgig.com/sitemap-index.xml)
- [Security contact](https://voxgig.com/.well-known/security.txt): RFC 9116.

## Optional

- [Podcast](https://voxgig.com/podcast): Fireside with Voxgig, 249+ episodes since 2018. [RSS](https://voxgig.com/podcast/rss.xml)
- [Blog](https://voxgig.com/voxgig-blog)
- [Case studies](https://voxgig.com/case-studies)
- [Privacy](https://voxgig.com/privacy)
- [Policy statements](https://voxgig.com/notices)
- [Generator source](https://github.com/voxgig/sdkgen): the open-source generator on GitHub.
- [Generated SDK repositories](https://github.com/voxgig-sdk)