Vellum

license

MIT(OSI, Copyright 2025 Vellum AI)

source

public(the full agent - gateway, clients, skill framework, memory - in github.com/vellum-ai/vellum-assistant)

core-gated

ungated(README: managed runtime on Vellum Platform or self-hosted, "Same codebase, same data model")

self-host

yes(by design)

managed-cloud

hosting convenience, not a feature tier

The agent's complete source is public and MIT-licensed (the LICENSE reads "Copyright (c) 2025 Vellum AI"), covering the backend gateway, the Mac, Slack and Telegram clients, the sandboxed skill framework and the memory system, and it is self-hostable by design rather than a client stub. The vendor's own marketing comparison table labels Vellum "Proprietary" against MIT for Hermes and OpenClaw, because it sells a managed cloud tier - but the same comparison post says outright that "Vellum is also open source", so that label is not a live caveat. The managed memory and security layer is not a feature tier either: the README states that the managed runtime and the self-hosted one are the "Same codebase, same data model", so hosting is a convenience rather than a gate, and a hosted offering sold alongside a complete open core is not gating.

• https://www.vellum.ai recorded 2026-08-13

  personal AI assistant 'AI layer for your life'; cloud or self-hosted, and it links to its own GitHub

• https://www.vellum.ai/blog/best-hermes-agent-alternatives recorded 2026-08-13

  Vellum positioning as a personal assistant against Hermes and OpenClaw; the post states outright "Vellum is also open source"

• https://github.com/vellum-ai/vellum-assistant recorded 2026-08-13

  PRIMARY - full open source agent source (gateway, clients, skill framework, memory) under an MIT license badge, 1.1k stars, 156 forks

• https://github.com/vellum-ai/vellum-assistant/blob/main/LICENSE recorded 2026-08-13

  PRIMARY - MIT License text, 'Copyright (c) 2025 Vellum AI'