Cloudflare has opened its Agents SDK to a harness it did not write. In Run the Pi Durable harness on Cloudflare with the Agents SDK, the changelog adds a PiHarness class so developers can build long-running agents with Pi 1.0 and Pi Durable, “ensuring your agent’s work is durably persisted, even if interrupted mid-turn.” It was built with Earendil, the company behind Pi, and Cloudflare calls it “our first step toward first-class support for third-party agent harnesses on Cloudflare.”
There are no figures in a changelog, and the post is plain about maturity: “PiHarness is in beta. Pi Durable is a new, experimental package, and the PiHarness API will likely change.” The design is the interesting part. Pi Durable provides the harness, and a new Agents SDK concept called the Lifecycle “is responsible for keeping the agent running in the Durable Object,” so long-running work can survive “restarts, crashes, and network issues.” Both Pi packages are optional peer dependencies, installed only if used. Models come through Workers AI or AI Gateway, or an existing Pi AI provider, and tools and system prompt sections arrive as extensions. The split matters: the harness decides how the agent reasons and acts, and the platform guarantees it keeps running.
The catalog holds the surfaces this rides on. The Cloudflare provider page lists 650 API pages, and the changelog lands on the Cloudflare Agents API and the Cloudflare Workers API, with model calls through the Cloudflare AI Gateway API. The record already carries a second harness page, Claude Managed Agents on Cloudflare API, which makes this the second third-party agent runtime on the platform the catalog has tracked. The agentic access profile maps 3,118 operations, 1,576 of them acting.
The Kin Score is 81.3, exemplar band, and Agent Readiness is 74.8, agent-native, the highest this series has recorded, with sixteen dimensions lit. Three days ago this series wrote that Cloudflare had made MCP authorization a library. This changelog does the same for agent durability: the platform owns staying alive, the harness owns the loop, and either can change without the other. The remaining unlit dimensions are the same three as before, a well-known catalog, agentic commerce and consent identity. A durable agent that can run for days on a user’s behalf is the case consent identity was written for. Cloudflare has made the agent hard to kill. The record has not yet shown how a user grants it the right to keep going.