diff --git a/README.md b/README.md
index 0554a428e..37ef6326f 100644
--- a/README.md
+++ b/README.md
@@ -191,6 +191,7 @@ This maps ~25 REST URL patterns and GraphQL queries to guard tool names, then ru
 | **Guard Response Labeling** | [docs/GUARD_RESPONSE_LABELING.md](docs/GUARD_RESPONSE_LABELING.md) — How guards label MCP responses with secrecy/integrity tags |
 | **HTTP Backend Sessions** | [docs/HTTP_BACKEND_SESSION_ID.md](docs/HTTP_BACKEND_SESSION_ID.md) — Session ID management for HTTP transport backends |
 | **Architecture Patterns** | [docs/MCP_SERVER_ARCHITECTURE_PATTERNS.md](docs/MCP_SERVER_ARCHITECTURE_PATTERNS.md) — MCP server design patterns and compatibility |
+| **Gateway Compatibility** | [docs/GATEWAY_COMPATIBILITY_QUICK_REFERENCE.md](docs/GATEWAY_COMPATIBILITY_QUICK_REFERENCE.md) — Quick reference for gateway compatibility |
 | **Security Model** | [docs/aw-security.md](docs/aw-security.md) — Security architecture overview |
 | **Contributing** | [CONTRIBUTING.md](CONTRIBUTING.md) — Development setup, building, testing, project structure |
 
diff --git a/docs/ENVIRONMENT_VARIABLES.md b/docs/ENVIRONMENT_VARIABLES.md
index 032ec39eb..c99a4bbd0 100644
--- a/docs/ENVIRONMENT_VARIABLES.md
+++ b/docs/ENVIRONMENT_VARIABLES.md
@@ -50,6 +50,16 @@ When using `run_containerized.sh`, these additional variables are available:
 | `DOCKER_HOST` | Docker daemon socket path | `/var/run/docker.sock` |
 | `DOCKER_API_VERSION` | Docker API version (set by helper scripts, Docker client auto-negotiates) | Set by querying Docker daemon's current API version; falls back to `1.44` if detection fails |
 
+## Proxy Mode Variables
+
+When running `awmg proxy`, these variables configure the upstream GitHub API:
+
+| Variable | Description | Default |
+|----------|-------------|---------|
+| `GITHUB_API_URL` | Explicit GitHub API endpoint (e.g., `https://copilot-api.mycompany.ghe.com`); used by proxy to set upstream target | (auto-derived) |
+| `GITHUB_SERVER_URL` | GitHub server URL; proxy auto-derives API endpoint: `*.ghe.com` → `copilot-api.*.ghe.com`, GHES → `<host>/api/v3`, `github.com` → `api.github.com` | (falls back to `api.github.com`) |
+| `GITHUB_TOKEN` / `GH_TOKEN` | GitHub auth token for the proxy to forward requests | (required) |
+
 ## DIFC / Guard Policy Configuration
 
 These environment variables configure guard policies (e.g., AllowOnly policies for restricting tool access to specific GitHub repositories):