feat: configurable block proposal graffiti

.env.sample.hoodi

@@ -178,6 +178,14 @@ MEV_RELAYS=https://0x98f0ef62f00780cf8eb06701a7d22725b9437d4768bb19b363e882ae871
 # Nickname to identify this charon node on monitoring (max 32 characters).
 #CHARON_NICKNAME=""
 
+# Graffiti to include in proposed blocks. Defaults to charon/<version>-<commit>.
+# A single value applies to all validators, or use a comma separated list with one entry per validator, ordered as in .charon/cluster-lock.json. Max 28 bytes per entry.
+# For no graffiti, set '""' (single quoted, so the inner quotes survive) and disable the client append below.
+#CHARON_GRAFFITI=
+
+# Disable the "OB<CL>" suffix charon appends to the graffiti, e.g. OBLH on Lighthouse. Increases the maximum to 32 bytes per entry.
+#CHARON_GRAFFITI_DISABLE_CLIENT_APPEND=false
+
 # Docker network of running charon node. See `docker network ls`.
 #CHARON_DOCKER_NETWORK=
 

.env.sample.mainnet

@@ -178,6 +178,14 @@ MEV_RELAYS=https://0xa15b52576bcbf1072f4a011c0f99f9fb6c66f3e1ff321f11f461d15e31b
 # Nickname to identify this charon node on monitoring (max 32 characters).
 #CHARON_NICKNAME=""
 
+# Graffiti to include in proposed blocks. Defaults to charon/<version>-<commit>.
+# A single value applies to all validators, or use a comma separated list with one entry per validator, ordered as in .charon/cluster-lock.json. Max 28 bytes per entry.
+# For no graffiti, set '""' (single quoted, so the inner quotes survive) and disable the client append below.
+#CHARON_GRAFFITI=
+
+# Disable the "OB<CL>" suffix charon appends to the graffiti, e.g. OBLH on Lighthouse. Increases the maximum to 32 bytes per entry.
+#CHARON_GRAFFITI_DISABLE_CLIENT_APPEND=false
+
 # Docker network of running charon node. See `docker network ls`.
 #CHARON_DOCKER_NETWORK=
 

CLAUDE.md

@@ -126,6 +126,7 @@ docker compose exec charon charon alpha test <suite> --publish   # infra | peers
 - `CHARON_BEACON_NODE_ENDPOINTS`: Override default beacon node (defaults to selected CL client)
 - `CHARON_FALLBACK_BEACON_NODE_ENDPOINTS`: Fallback beacon nodes for redundancy
 - `BUILDER_API_ENABLED`: Enable/disable MEV-boost integration
+- `CHARON_GRAFFITI`, `CHARON_GRAFFITI_DISABLE_CLIENT_APPEND`: Block proposal graffiti (set on charon, not the VC)
 - `CLUSTER_NAME`, `CLUSTER_PEER`: Required for monitoring with Alloy/Prometheus
 - `ALERT_DISCORD_IDS`: Discord IDs for Obol Agent monitoring alerts
 

docker-compose.yml

@@ -101,6 +101,8 @@ services:
       - CHARON_VALIDATOR_API_ADDRESS=0.0.0.0:3600
       - CHARON_MONITORING_ADDRESS=0.0.0.0:3620
       - CHARON_BUILDER_API=${BUILDER_API_ENABLED:-true}
+      - CHARON_GRAFFITI=${CHARON_GRAFFITI:-}
+      - CHARON_GRAFFITI_DISABLE_CLIENT_APPEND=${CHARON_GRAFFITI_DISABLE_CLIENT_APPEND:-false}
       - CHARON_FEATURE_SET_ENABLE=${CHARON_FEATURE_SET_ENABLE:-}
       - CHARON_LOKI_ADDRESSES=${CHARON_LOKI_ADDRESSES:-http://loki:3100/loki/api/v1/push}
       - CHARON_LOKI_SERVICE=charon