# Cloudflare Agents SDK

Cloudflare's Agents SDK now treats Agent Skills as files in the agent's workspace: write a folder containing SKILL.md under /workspace/.agents/skills/ and the agent can use it on its next turn, with no build step or deploy, and the agent can write its own skills. Skills load from a workspace, an R2 bucket, or code, and Think lists every source again before each turn; each SKILL.md is checked against the Agent Skills specification, and a skill that breaks a rule still loads with a logged warning. This is a breaking change: direct agents/skills use, the Vite import, SkillRegistry, and Think's skillWorkspace are removed.

Cloudflare's Agents SDK now treats Agent Skills as files in the agent's workspace: write a folder containing SKILL.md under /workspace/.agents/skills/ and the agent can use it on its next turn, with no build step or deploy, and the agent can write its own skills. Skills load from a workspace, an R2 bucket, or code, and Think lists every source again before each turn; each SKILL.md is checked against the Agent Skills specification, and a skill that breaks a rule still loads with a logged warning. This is a breaking change: direct agents/skills use, the Vite import, SkillRegistry, and Think's skillWorkspace are removed.

Cloudflare added internal hostnames to the persistent browser in its Agents SDK: give the browser a name such as preview.internal and requests to it go to the agent itself rather than the internet. The agent can then check a dev server in its sandbox, a folder in its workspace, or another Worker in the same browser it uses for the web, with nothing exposed publicly. Each internal host has a fetch function running in the Durable Object, so it can use that object's bindings and state, and a host can carry a target schema so the model chooses which port or folder it serves.

Cloudflare added internal hostnames to the persistent browser in its Agents SDK: give the browser a name such as preview.internal and requests to it go to the agent itself rather than the internet. The agent can then check a dev server in its sandbox, a folder in its workspace, or another Worker in the same browser it uses for the web, with nothing exposed publicly. Each internal host has a fetch function running in the Durable Object, so it can use that object's bindings and state, and a host can carry a target schema so the model chooses which port or folder it serves.