Ask HN: Enterprise Agent Orchestration Recommendations?

I've been made tech lead for our internal Agentic Platform and Experience. This effort will support both the developers and business teams. It would be nice to have cohesion, but it is not a requirement.

The core bounds are:

1. We are largely Google Cloud based, Vertex Ai is solid

2. Some freedom in tool choice (claude, gemini, codex, opencode, ADK, and their Desktop equivalents)

3. Compliance and auditing, hence "enterprise"

4. Human in the loop and agent customization (prompts, skills, harness, sandbox, DAGs)

5. The platform and agents should run in the cloud, not on local machines. GKE (Kubernetes) + OCI makes a lot of sense here.

Initial research has the following leading the pack

A. Vertex Ai, hard to beat GCP's ability to serve models and the various tools can be configured to use Vertex Ai instead of the "oem" APIs.

B. Scion[1] as the Agent Orchestration framework for developers. Handles the various CLIs, custom harness images, lots of customization points. It's still early, but looks very promising, eg. you can reimplement Gastown and much more.

C. Gemini Enterprised, announced at Google Cloud Next, looks to be something the business team would use more than developers. This has a lot of overlap with Scion.

What alternatives should I be looking at?

Are there any major considerations I'm missing?

[1] https://googlecloudplatform.github.io/scion/overview/