a16z Podcast
Stainless founder Alex Rattray joins a16z partner Jennifer Li to talk about the future of APIs, SDKs, and the rise of MCP (Model Context Protocol). Drawing on his experience at Stripe—where he helped redesign API docs and built code-generation systems—Alex explains why the SDK is the API for most developers, and why high-quality, idiomatic libraries are essential not just for humans, but now for AI agents as well.
They dive into:
- The evolution of SDK generation and lessons from building at scale inside Stripe.
- Why MCP reframes APIs as interfaces for large language models.
- The challenges of designing tools and docs for both developers and AI agents.
- How context limits, dynamic tool generation, and documentation shape agent usability.
- The future of developer platforms in an era where “every company is an API company.”
Timecodes:
0:00 – Introduction: APIs as the Dendrites of the Internet
1:49 – Building API Platforms: Lessons from Stripe
3:03 – SDKs: The Developer’s Interface
6:16 – The MCP Model: APIs for AI Agents
9:23 – Designing for LLMs and AI Users
13:08 – Solving Context Window Challenges
16:57 – The Importance of Strongly Typed SDKs
21:07 – The Future of API and Agent Experience
24:45 – Lessons from Leading API Companies
26:14 – Outro and Disclaimers
Resources:
Find Alex on X: https://x.com/rattrayalex
Find Jennifer on X: https://x.com/JenniferHli
Stay Updated:
Let us know what you think: https://ratethispodcast.com/a16z
Find a16z on Twitter: https://twitter.com/a16z
Find a16z on LinkedIn: https://www.linkedin.com/company/a16z
Subscribe on your favorite podcast app: https://a16z.simplecast.com/
Follow our host: https://x.com/eriktorenberg
Please note that the content here is for informational purposes only; should NOT be taken as legal, business, tax, or investment advice or be used to evaluate any investment or security; and is not directed at any investors or potential investors in any a16z fund. a16z and its affiliates may maintain investments in the companies discussed. For more details please see a16z.com/disclosures.

-
A Big Week in Tech: NotebookLM, OpenAI’s Speech API, & Custom Audio
Last week was another big week in technology. Google’s NotebookLM introduced its Audio Overview feature, enabling users to create customizable podcasts in over 35 languages. OpenAI followed with their real-time speech-to-speech API, making voice integration…
-
From Swipe to Scale: How Tinder Became #1
In 1995, just 2% of couples met online. Today, that number has surged to over 50%, making online dating the top way couples connect. In this episode, a16z General Partner Andrew Chen chats with Tinder…
-
Human Data is Key to AI: Alex Wang from Scale AI
What if the key to unlocking AI’s full potential lies not just in algorithms or compute, but in data? In this episode, a16z General Partner David George sits down with Alex Wang, founder and CEO…
-
The Frontier of Spatial Intelligence with Fei-Fei Li
Fei-Fei Li and Justin Johnson are pioneers in AI. While the world has only recently witnessed a surge in consumer AI, our guests have long been laying the groundwork for innovations that are transforming industries…
-
Apple’s Big Reveals, OpenAI’s Multi-Step Models, and Firefly Does Video
This week in consumer tech: Apple’s big reveals, OpenAI’s multi-step reasoning, and Adobe Firefly’s video model. Olivia Moore and Justine Moore, Partners on the a16z Consumer team, break down the latest announcements and how these…
-
Grand Challenges in Healthcare AI
Vijay Pande, founding general partner, and Julie Yoo, general partner at a16z Bio + Health, come together to discuss the grand challenges facing healthcare AI today. The talk through the implications of AI integration in…
-
Governing democracy, the internet, and boardrooms
with @NoahRFeldman, @ahall_research, @rhhackett Welcome to web3 with a16z. I’m Robert Hackett and today we have a special episode about governance in many forms — from nation states to corporate boards to internet services and…
-
It’s Time to Build in Healthcare
Half of prescribed medications are never taken, and 88% of Americans are metabolically unhealthy. Despite spending 20% of our GDP on healthcare—twice that of any other developed nation—our outcomes still lag behind. In this episode,…
-
Latin America: A Tech Powerhouse?
Latin America is emerging as a tech powerhouse, but it’s not a one-size-fits-all market. In this episode, we explore why what works in Argentina won’t necessarily fly in Brazil or Mexico, and how companies are…
-
The SSN Breach: What Now?
In this episode, we cover the recent data breach of nearly 3B records, including a significant number of social security numbers. Joining us to discuss are security experts Joel de la Garza and Naftali Harris.…