diff --git a/README.md b/README.md
index d3d19bbbb..52dd475ce 100644
--- a/README.md
+++ b/README.md
@@ -164,3 +164,6 @@ The core team will review opened PRs. The SLA is 2 weeks, generally on a first-c
 ## Storybook for UI components
 
 See `storybook/README.md` for details on local Storybook and component docs.
+## Additional Note
+
+When building on Base, always ensure that you are using the correct RPC endpoint for the intended network (mainnet or testnet). Misconfiguration can lead to failed transactions or unexpected behavior.
diff --git a/docs/base-chain/node-operators/base-v1-upgrade.mdx b/docs/base-chain/node-operators/base-v1-upgrade.mdx
index 46325ef6b..3420e7e3c 100644
--- a/docs/base-chain/node-operators/base-v1-upgrade.mdx
+++ b/docs/base-chain/node-operators/base-v1-upgrade.mdx
@@ -117,6 +117,7 @@ If you use [base/node](https://github.com/base/node), most variables are already
 | `OP_NODE_L1_TRUST_RPC` | `BASE_NODE_L1_TRUST_RPC` |
 | `OP_NODE_L2_ENGINE_RPC` | `BASE_NODE_L2_ENGINE_RPC` |
 | `OP_NODE_L2_ENGINE_AUTH` | `BASE_NODE_L2_ENGINE_AUTH` |
+| — | `BASE_NODE_L2_ENGINE_AUTH_RAW` |
 | — | `BASE_NODE_L2_ENGINE_AUTH_ENCODED` |
 | `OP_NODE_P2P_BOOTNODES` | `BASE_NODE_P2P_BOOTNODES` |
 | `OP_NODE_P2P_LISTEN_IP` | `BASE_NODE_P2P_LISTEN_IP` |
@@ -151,6 +152,7 @@ If you use [base/node](https://github.com/base/node), most variables are already
 
 ## FAQ
 
+- **Do I need to set `BASE_NODE_L2_ENGINE_AUTH_RAW`?** Yes — this must be set to a secure random hex string shared between the execution and consensus containers. Generate one with `openssl rand -hex 32`. Nodes using host networking or custom port mappings that rely on the default placeholder value are exposed to unauthenticated Engine API access.
 - **Do I need to re-sync?** Not if you are already running OP Reth. Existing data is compatible.
 - **What if I'm on `op-geth` or `nethermind`?** You need to switch to `base-reth-node`. Use a [Reth snapshot](/base-chain/node-operators/snapshots) to bootstrap.
 - **Do OP namespace RPCs still work?** Yes, all existing RPCs are supported.