diff --git a/CONVENTIONS.md b/CONVENTIONS.md
index abc28a5..0b0fce5 100644
--- a/CONVENTIONS.md
+++ b/CONVENTIONS.md
@@ -98,7 +98,7 @@ README.
 
 ## The engine
 
-- Pure and deterministic: `create(names, seed, rules)` and
+- Pure and deterministic: `create(names, seed, rules, options)` and
   `resolve(state, inputs)` are functions of their arguments with a seeded
   generator inside the state. Bots are functions of the state too. This is
   what lets a ledger be the whole record.