Engineering at Anthropic Harness design for long-running application development Written by Prithvi Rajasekaran, a member of our Labs team. Over the past several months I’ve been working on two interconnected…
…Subagents raise new questions about how users can understand and steer workflows that are no longer neatly visible as a single thread of actions. We are exploring different coordination patterns to address…
…And because code is deterministic, this workflow is consistent and repeatable. Developing and evaluating skills Here are some helpful guidelines for getting started with authoring and testing skills: Start with evaluation: Identify…
Engineering at Anthropic Introducing advanced tool use on the Claude Developer Platform The future of AI agents is one where models work seamlessly across hundreds or thousands of tools. An IDE assistant…
…Model Context Protocol The Model Context Protocol is an open standard that enables developers to build secure, two-way connections between their data sources and AI-powered tools. The architecture is straightforward…
…This workflow allows for separation of concerns, and building more specialized prompts. Without this workflow, optimizing for one kind of input can hurt performance on other inputs. When to use this workflow…
…Early testing shows Claude Opus 4.6 delivering on the complex, multi-step coding work developers face every day—especially agentic workflows that demand planning and tool calling. This starts unlocking long…
…Combined with faster median latency and strict instruction following, it’s particularly meaningful for complex, long-running coding workflows. It cuts the friction from those multi-step tasks so developers can stay…
…Improvements in consistency, instruction following, and more have made developers with early access prefer Sonnet 4.6 to its predecessor by a wide margin. They often even prefer it to our smartest…
…If you’re a developer, simply use claude-opus-4-5-20251101 via the Claude API . Pricing is now $5/$25 per million tokens—making Opus-level capabilities accessible to even more…