Project Think: Building the Next-Generation AI Agents on Cloudflare

Cloudflare has extended its existing Agents SDK through Project Think. The goal is to provide fundamental primitives for long-running agents, allowing developers to build safer, more scalable agents with less configuration.

The core idea is treating agents as infrastructure-level units of execution. Each agent operates as an actor model based on Durable Objects, with zero compute cost while dormant, and automatically wakes up when a message or alarm arrives. Cloudflare explains that by providing per-agent SQLite state, name-based routing, automatic restarts, and state preservation, this is far more economical at large-scale concurrent sessions than an always-on container architecture.

The key primitives are as follows.

• Fibers: Durably execute long-running tasks via runFiber(), with support for checkpointing and recovery
• Facets: Co-locate sub-agents isolated from the parent to separate tasks
• Session API: Stores conversations in a tree structure, supporting forking, summary compression, and FTS5 search
• Dynamic Workers: A sandboxed JS execution environment with no network access by default
• Execution Ladder: Progressive scaling from Workspace → Dynamic Worker → npm bundling → headless browser → Cloudflare Sandbox

Cloudflare specifically believes that having an LLM write a single program to handle a system is more efficient than the existing repeated tool-calling loop. To this end, it provides standalone packages such as @cloudflare/codemode, @cloudflare/worker-bundler, and @cloudflare/shell, and proposes a structure that only escalates to a stronger execution environment when needed.

Another axis is self-authored extensions. Agents can directly create and deploy new tools during execution, and these extensions are sandboxed, auditable, and revocable within a Dynamic Worker. As a result, agents evolve into something closer to a serverless execution platform equipped with persistence, isolation, security, and scalability, rather than a simple chatbot.