Software Engineer, Agent SDK - Claude Code

Anthropic•Seattle, WA

2d•Hybrid

About The Position

About Anthropic Anthropic’s mission is to create reliable, interpretable, and steerable AI systems. We want AI to be safe and beneficial for our users and for society as a whole. Our team is a quickly growing group of committed researchers, engineers, policy experts, and business leaders working together to build beneficial AI systems. About Anthropic Anthropic's mission is to create reliable, interpretable, and steerable AI systems. We want AI to be safe and beneficial for our users and for society as a whole. Our team is a quickly growing group of committed researchers, engineers, policy experts, and business leaders working together to build beneficial AI systems. The Role The Claude Agent SDK is the foundational layer that powers autonomous AI agents — giving developers access to the same tools, agent loop, and context management that power Claude Code, programmable in Python and TypeScript. It's what enables agents to read files, run commands, search the web, edit code, and more, out of the box. We're looking for a Software Engineer to own and lead the Agent SDK. This is a high-ownership, high-autonomy role: you'll set the technical direction for the SDK, be opinionated about its API design and developer experience, and be the connective tissue between internal teams building next-generation experiences (Claude Desktop, Cowork, IDE extensions) and external developers building production agents on top of Claude. You'll need to exercise taste and judgment about what to build — balancing a rich stream of requests from internal stakeholders and external customers against a clear product vision for what a great agentic SDK should be.

Requirements

Have strong opinions about what great developer tools look like, grounded in experience building or using them
Are energized by owning something end-to-end, from API design through docs through developer adoption
Have experience designing and shipping developer-facing SDKs or APIs, and have felt the difference between an SDK that developers love and one they merely tolerate
Are excited about the frontier of agentic AI — agents that can reason, plan, and act autonomously
Have hands-on experience with agentic patterns: tool use, orchestration, context management, multi-step reasoning
Can operate independently in ambiguous environments and push projects forward without waiting for direction
Care about the societal implications of the technology you build
Have 5+ years of software engineering experience

Nice To Haves

Maintained a project built on the Claude Agent SDK
Experience managing an open source project on GitHub — triaging issues, prioritizing what to take on and engaging with community contributors
Experience scaling TypeScript or Python library codebases
Shipped SDKs or APIs used by external developers in production
Opinions about API versioning, backwards compatibility, and managing ecosystem migrations

Responsibilities

Own the roadmap and technical direction for the Claude Agent SDK (Python and TypeScript)
Design clean, intuitive APIs that make it easy to build powerful, reliable agents
Partner closely with internal teams building on Agent SDK — including Claude Desktop, Cowork, and IDE extensions — to understand their needs and prioritize accordingly
Engage directly with external developers to understand how they're using the SDK, where they're hitting friction, and what unlocks the next generation of use cases
Raise the quality bar on documentation, examples, and the overall developer experience
Collaborate with other Claude Code engineers to expose new model capabilities through clean SDK abstractions