Anthropic updates Agent Skills with programmable subagents

Agent Skills signals a shift from "chatbots with instructions" to "distributed agentic programs" capable of high-reliability automation. By open-sourcing the standard via agentskills.io, Anthropic is positioning its framework as the universal middleware for the agentic era.

• –The "context: fork" field enables agents to spawn isolated subagents, solving the context-window saturation problem that typically degrades long-running agent performance.
• –The "Bloom" framework brings software engineering rigor to LLM agents by making "eval-driven development" and automated CI/CD testing a prerequisite for deployment.
• –Modular "work handover packages" allow skills to be portable across IDEs and platforms, directly challenging the walled-garden approach of vendor-specific agent ecosystems.
• –This release provides the technical foundation for Claude Cowork, moving Anthropic beyond simple assistance and into direct competition with enterprise RPA and workflow automation tools.