Unique Engineering Highlights

Reasoning/execution separation

The plan makes LangGraph responsible for durable reasoning and the executor responsible for isolation, staging, execution, and persistence. This boundary limits blast radius and allows either side to evolve.

Workspace manifest diffing

Before execution, the executor captures a hashed manifest; after execution, it persists changed and deleted files. This turns an ephemeral VM workspace into durable agent artifacts without copying everything blindly.

Lease reconciliation

The runtime manager persists leases and cleans unknown sandboxes/workspaces at startup. It also flushes dirty workspaces when runtime configuration changes, addressing crash and restart behavior directly.

Artifact-forward UX

The frontend treats generated CSV, images, HTML, code, and Markdown as first-class viewers rather than burying outputs in chat text.

Resumability as a three-store contract

Checkpoints, thread-to-sandbox mappings, and object storage must recover together. That is a more precise model than “the chat is persisted.”