diff --git a/modules/build-agent/README.md b/modules/build-agent/README.md
index a27d2c45..cb960f5c 100644
--- a/modules/build-agent/README.md
+++ b/modules/build-agent/README.md
@@ -15,6 +15,6 @@ Assign it to every machine with a container runtime. It replaces `builder`, the
 same thing; retire that once this is assigned where it was.
 
 A send that replaces the agent's container does not throw away the build it runs: the container declares
-`busy` as `mesh-builder busy` (novox/hq ADR 0335). The node-engine asks it before replacing it; from that
+`busy` as `/usr/local/bin/mesh-builder busy` (novox/hq ADR 0335). The node-engine asks it before replacing it; from that
 ask the agent takes no new build, the node-engine leaves it running while it says a build is in hand, and
 replaces it once it says idle, or after 15 minutes at the latest.
diff --git a/modules/build-agent/module.json b/modules/build-agent/module.json
index ed8d6190..ecb9c6c8 100644
--- a/modules/build-agent/module.json
+++ b/modules/build-agent/module.json
@@ -80,7 +80,7 @@
         "grace": "60s"
       },
       "busy": {
-        "command": "mesh-builder busy"
+        "command": "/usr/local/bin/mesh-builder busy"
       }
     }
   ],