---
title: "Why client SDK generation belongs in the open"
description: "Google describes partnering with Speakeasy to open-source the OpenAPI code-generation suite used for new SDKs for its Interactions, Agents, and Webhooks APIs. The change follows the May 2026 shutdown of a proprietary SDK-generation provider, which exposed platform risk while Google was preparing the Interactions API for general availability; migration prioritized avoiding breaking changes and preserving type definitions, strict error hierarchies, and streaming behavior. The AGPLv3 suite generates statically typed libraries for Python, TypeScript, Go, Java, C#, PHP, and Ruby, plus standalone agent-native CLI binaries and documentation MCP servers built from OpenAPI specifications and Markdown. Google says a deterministic generator paired with Antigravity AI agents now supports its pipeline across six targets, including three released SDKs, with roughly one engineer maintaining it, while generated code can remain under a chosen license such as MIT or Apache 2.0."
---

# Why client SDK generation belongs in the open

[Google](https://yomu.fyi/company/google) · Amir Hardon, Philipp Schmid · Sep 17, 2026

**Type:** Announcement

## Summary

Google describes partnering with Speakeasy to open-source the OpenAPI code-generation suite used for new SDKs for its Interactions, Agents, and Webhooks APIs. The change follows the May 2026 shutdown of a proprietary SDK-generation provider, which exposed platform risk while Google was preparing the Interactions API for general availability; migration prioritized avoiding breaking changes and preserving type definitions, strict error hierarchies, and streaming behavior. The AGPLv3 suite generates statically typed libraries for Python, TypeScript, Go, Java, C#, PHP, and Ruby, plus standalone agent-native CLI binaries and documentation MCP servers built from OpenAPI specifications and Markdown. Google says a deterministic generator paired with Antigravity AI agents now supports its pipeline across six targets, including three released SDKs, with roughly one engineer maintaining it, while generated code can remain under a chosen license such as MIT or Apache 2.0.

## Context

The announcement responds to the abrupt shutdown of a proprietary SDK-generation provider in May 2026, during preparation for the General Availability of the Interactions API. It frames closed-source client-generation tooling as platform risk and argues that tooling for compiling OpenAPI interfaces should be open infrastructure.

## Approach / What changed

Google partnered with Speakeasy to migrate its client libraries in place, aligning type definitions across target languages, preserving strict error hierarchies and streaming behavior, and integrating the generator into its internal monorepo and build system. The resulting setup uses a fast, deterministic generator for formal API specifications and Antigravity AI agents for custom SDK work.

## Takeaways

- The open-sourced suite generates statically typed SDKs for Python, TypeScript, Go, Java, C#, PHP, and Ruby, with SSE streaming, retries, and pagination.
- It also generates standalone CLI binaries for agent use and documentation MCP servers that combine OpenAPI specifications with Markdown documentation.
- The generator is AGPLv3-licensed, while generated SDKs can remain under a chosen license such as MIT or Apache 2.0; modifications to the compiler remain open under AGPL terms.

## FAQ

### What prompted the move from proprietary SDK generation to open tooling?

The SDK-generation provider Google was using was acquired and announced its shutdown in May 2026. Google says the disruption exposed platform risk in relying on closed-source generators.

### What does the open-sourced Speakeasy suite generate?

It generates client libraries for seven languages, standalone CLI binaries, and documentation MCP servers. The SDKs include static typing, server-sent events streaming, retries, and pagination.

### Does AGPLv3 require generated SDKs to use AGPLv3?

No. The source says developers can keep complete ownership of generated code and SDKs under a chosen license, such as MIT or Apache 2.0. Changes to the generator compiler itself remain open to the community under AGPLv3.

**Tags:** [AI Agents](https://yomu.fyi/topic/ai-agents), [MCP](https://yomu.fyi/topic/mcp), [OpenAPI](https://yomu.fyi/topic/openapi), [Open Source](https://yomu.fyi/topic/open-source)

- Source: [Google](https://developers.googleblog.com/why-client-sdk-generation-belongs-in-the-open)
- Source URL: https://developers.googleblog.com/why-client-sdk-generation-belongs-in-the-open
- Ingested by Yomu: 2026-09-17T21:00:11.559Z

[Read original post](https://developers.googleblog.com/why-client-sdk-generation-belongs-in-the-open)