more checks on shrinking

1 files changed, 10 insertions, 0 deletions

diff --git a/pbt/ts/src/bank.ts b/pbt/ts/src/bank.ts
index bee9dfc..c5adc05 100644
--- a/pbt/ts/src/bank.ts
+++ b/pbt/ts/src/bank.ts
@@ -5,6 +5,16 @@ export type Account = string;
 
 export interface Bank {
   balance: (account: Account) => Option<number>;
+
+  /// Deposit amount into account
+  ///
+  /// This function increases the balance of the given account by the
+  /// specified amount. It's a `void` function hence implicitly
+  /// stateful: It's expected to change some internal state of the
+  /// implementing class.
+  ///
+  /// @param account The account to deposit into
+  /// @param amt The amount to deposit
   deposit: (account: Account, amt: number) => void;
   withdraw: (account: Account, amt: number) => void;
 }