SYSTEM Cited by 3 sources

Flue¶

Flue (flueframework.com) is an open-source declarative agent framework (1.0 Beta, June 2026) built by the team behind Astro. It sits at the framework layer of the three-layer agent platform stack (framework → harness → runtime), built on the Pi harness (same harness powering OpenClaw).

Architecture¶

Flue's core design principle: describe what an agent knows, not what it does. Define model, skills, sandbox, and instructions declaratively — the agent solves tasks autonomously with no orchestration loop to write.

Deployment targets¶

Node.js: each agent runs as a long-lived process; deployable to any VM, container, or GitHub Actions.
Cloudflare: each agent becomes a Durable Object with isolated storage and compute, automatic scaling, no server provisioning or sticky sessions.

Durable Streams¶

Flue achieves crash recovery via Durable Streams — an append-only event log where every prompt, tool response, and model choice is recorded as an immutable entry. On process death, a new instance replays the log from the exact interrupted step.

(Source: Agents platform post.)

Cloudflare integration¶

When targeting Cloudflare, Flue leverages:

runFiber() / stash() / onFiberRecovered() for durable execution
@cloudflare/codemode for sandboxed code execution via Code Mode
@cloudflare/shell for a durable virtual filesystem

Seen in¶

sources/2026-06-17-cloudflare-bringing-more-agent-harnesses-and-frameworks-to-cloudflare — launch announcement with architectural decomposition
sources/2026-08-04-cloudflare-agent-development-lifecycle — pairs Flue agents with durable Workflows in Cloudflare's proposed agent-operated delivery control plane. The example shows a Workflow explicitly choosing when to dispatch an agent and how to retain its result as stage context.

systems/pi-harness — underlying agentic-loop harness
systems/cloudflare-agents-sdk — runtime layer Flue targets
systems/project-think — Cloudflare's first-party harness (same SDK primitives)
declarative-agent-definition — Flue's core design principle
framework-harness-runtime-layering — the stack separation Flue exemplifies

Astro issue-triage factory (2026-08-04)¶

Astro demonstrates Flue as the framework underneath a GitHub-issue repair workflow: event-triggered triage runs a reusable skill in GitHub Actions, separates reproduce → diagnose → verify → fix into isolated subagents, and records handoffs in report.md. The post reinforces Flue’s platform-agnostic framing: a GitHub issue is merely one event source, alongside potential Slack, cron, or webhook triggers. (Source: sources/2026-08-04-cloudflare-astro-issue-triage)