diff --git a/tools/sim/README.md b/tools/sim/README.md
index f6ddde2580..ff95d16de6 100644
--- a/tools/sim/README.md
+++ b/tools/sim/README.md
@@ -4,7 +4,7 @@ openpilot in simulator
 openpilot implements a [bridge](run_bridge.py) that allows it to run in the [MetaDrive simulator](https://github.com/metadriverse/metadrive).
 
 ## Launching openpilot
-First, start openpilot.
+First, start openpilot. Note that you will either need a [mapbox token](https://docs.mapbox.com/help/getting-started/access-tokens/#how-access-tokens-work) (set with ```export MAPBOX_TOKEN="1234"```), or to disable mapsd with ```export BLOCK=mapsd```
 ``` bash
 # Run locally
 ./tools/sim/launch_openpilot.sh