Short answer

Proxy groups are not node protocols; they organize nodes for manual selection, testing, fallback, load balancing or relay chains. In real use, trust the provider subscription first and then verify whether the selected client core supports this exact type.

What It Means

In Clash/Mihomo configuration, select / url-test / fallback / load-balance / relay identifies the outbound type used by the node, policy or group. The same display name in a GUI can hide different transport fields, so the YAML or subscription output is more reliable than the node nickname.

Common Fields

type: select
type: url-test
type: fallback
type: load-balance
type: relay
proxies / use

When to Use It

After import you see groups such as Proxy, Auto or Fallback.
Nodes should be selected automatically by latency or availability.
Rules need to reference a group instead of a single node.

Support Checks Checks

A group references nodes; it does not create usable routes by itself.
url-test/fallback test URL, interval and timeout affect results.
relay chains can amplify latency and connection symptom rates.

Minimal Shape

proxy-groups:
- name: "Proxy"
  type: select
  proxies:
    - Auto
    - DIRECT
- name: "Auto"
  type: url-test
  proxies:
    - ss-node
    - trojan-node
  url: https://www.gstatic.com/generate_204
  interval: 300

Compatibility Notes

Client support changes with the bundled core. A maintained Mihomo-based client usually supports more modern node types than historical Clash clients, but mobile clients and iOS alternatives still vary by app and release.

If a subscription contains this type but the client filters it out, switch to a compatible client, ask the provider for a compatible subscription format, or use a converter only when you understand what fields are being changed.

Official Reference

Proxy Groups in Mihomo docs

Proxy Groups Protocol