diff --git a/ui/src/components/DisplayAmount.tsx b/ui/src/components/DisplayAmount.tsx
index fa289e2c..b90a8ca3 100644
--- a/ui/src/components/DisplayAmount.tsx
+++ b/ui/src/components/DisplayAmount.tsx
@@ -1,6 +1,6 @@
 import type { PurseJSONState } from '@agoric/react-components';
 import type { DisplayInfoForBrand } from '../store/displayInfo';
-import { stringifyValue, type AssetKind } from '@agoric/web-components';
+import { stringifyValue} from '@agoric/web-components';
 import type { Amount } from '@agoric/ertp/src/types';
 import { isCopyBagValue } from '@agoric/ertp';
 import { useEffect, useRef, useState } from 'react';
@@ -10,7 +10,7 @@ export const PurseValue = ({
   purse,
   allowPopup,
 }: {
-  purse: PurseJSONState<AssetKind>;
+  purse: PurseJSONState<'nat' | 'copyBag' | 'set'>;
   allowPopup?: boolean;
 }) => {
   const displayInfoForBrand: DisplayInfoForBrand = {
@@ -65,7 +65,7 @@ export const NonNatValue = ({
   petname,
   allowPopup = true,
 }: {
-  value: Amount<'set'>['value'] | Amount<'copyBag'>['value'];
+  value: Amount['value'];
   petname: string;
   allowPopup?: boolean;
 }) => {
@@ -86,24 +86,23 @@ export const NonNatValue = ({
 
   const count = isCopyBag
     ? String(
-        value.payload.reduce(
-          // @ts-expect-error cast
+        (value as Amount<'copyBag'>['value']).payload.reduce(
           // eslint-disable-next-line @typescript-eslint/no-unused-vars
           (total, [_, count]) => total + count,
           0n,
         ),
       )
-    : value.length;
+    : (value as Amount<'set'>['value']).length;
 
   const items = isCopyBag
-    ? value.payload.map((entry: [unknown, bigint]) => (
+    ? (value as Amount<'copyBag'>['value']).payload.map((entry: [unknown, bigint]) => (
         <CopyBagEntry
           key={stringifyData(entry[0])}
           className="mb-4"
           entry={entry}
         />
       ))
-    : value.map((entry: unknown) => (
+    : (value as Amount<'set'>['value']).map((entry: unknown) => (
         <SetEntry className="mb-4" key={stringifyData(entry)} entry={entry} />
       ));
 
diff --git a/ui/src/components/PurseAmountInput.tsx b/ui/src/components/PurseAmountInput.tsx
index dbb1ecc0..31e177f3 100644
--- a/ui/src/components/PurseAmountInput.tsx
+++ b/ui/src/components/PurseAmountInput.tsx
@@ -1,12 +1,13 @@
 import { AmountInput, type PurseJSONState } from '@agoric/react-components';
-import type { Amount, AssetKind } from '@agoric/web-components';
+import type { AssetKind } from '@agoric/web-components';
 import { useState } from 'react';
 import { CopyBagEntry, PurseValue, SetEntry } from './DisplayAmount';
 import { stringifyData } from '../utils/stringify';
-import { makeCopyBag } from '@endo/patterns';
+import { makeCopyBag, Key } from '@endo/patterns';
 
 type Props = {
   purse: PurseJSONState<AssetKind>;
+  onChangeInput?: (amount: {brand: globalThis.Brand, value: unknown} | null) => void;
   onChange: (amount: Amount | null) => void;
 };
 
@@ -35,7 +36,7 @@ const PurseAmountInput = (props: Props) => {
   return <></>;
 };
 
-const SetInput = ({ purse, onChange }: Props) => {
+const SetInput = ({ purse, onChangeInput }: Props) => {
   const entries = purse.currentAmount.value;
   const [checkedEntries, setCheckedEntries] = useState(new Set<unknown>());
 
@@ -48,13 +49,13 @@ const SetInput = ({ purse, onChange }: Props) => {
       updated.add(entry);
     }
     if (!updated.size) {
-      onChange(null);
+      onChangeInput?.(null);
     } else {
       const newAmount = {
         brand: purse.brand,
         value: [...updated],
       };
-      onChange(newAmount);
+      onChangeInput?.(newAmount);
     }
     setCheckedEntries(updated);
   };
@@ -85,13 +86,13 @@ const SetInput = ({ purse, onChange }: Props) => {
   });
 };
 
-const CopyBagInput = ({ purse, onChange }: Props) => {
+const CopyBagInput = ({ purse, onChangeInput }: Props) => {
   const entries = purse.currentAmount.value.payload;
   const [entriesMap, setEntriesMap] = useState(
-    new Map<string, [unknown, bigint]>(),
+    new Map<string, [Key, bigint]>(),
   );
 
-  const updateCount = (entry: [unknown, bigint], count: bigint) => {
+  const updateCount = (entry: [Key, bigint], count: bigint) => {
     const updated = new Map(entriesMap);
     if (count === 0n) {
       updated.delete(stringifyData(entry[0]));
@@ -99,18 +100,18 @@ const CopyBagInput = ({ purse, onChange }: Props) => {
       updated.set(stringifyData(entry[0]), [entry[0], count]);
     }
     if (count > entry[1]) {
-      onChange(null);
+      onChangeInput?.(null);
     } else {
       const newAmount = {
         brand: purse.brand,
         value: makeCopyBag(updated.values()),
       };
-      onChange(newAmount);
+      onChangeInput?.(newAmount);
     }
     setEntriesMap(updated);
   };
 
-  return entries.map((entry: [unknown, bigint]) => {
+  return entries.map((entry: [Key, bigint]) => {
     const selectedAmount = entriesMap.get(stringifyData(entry[0]))?.[1] ?? null;
 
     const onInput = (count: bigint) => {
@@ -143,16 +144,16 @@ const CopyBagInput = ({ purse, onChange }: Props) => {
   });
 };
 
-const NatAmountInput = ({ purse, onChange }: Props) => {
+const NatAmountInput = ({ purse, onChangeInput }: Props) => {
   const [amount, setAmount] = useState({ brand: purse?.brand, value: 0n });
   const hasError = amount.value > purse.currentAmount.value;
 
   const onInputChange = (value: bigint) => {
     const newAmount = { brand: purse?.brand, value };
     if (value > purse.currentAmount.value || value === 0n) {
-      onChange(null);
+      onChangeInput?.(null);
     } else {
-      onChange(newAmount);
+      onChangeInput?.(newAmount);
     }
     setAmount(newAmount);
   };
diff --git a/ui/src/components/swap/IncomingOffers.tsx b/ui/src/components/swap/IncomingOffers.tsx
index bf30eed0..554de632 100644
--- a/ui/src/components/swap/IncomingOffers.tsx
+++ b/ui/src/components/swap/IncomingOffers.tsx
@@ -7,10 +7,12 @@ const IncomingOffers = () => {
   const { instances } = useContractStore();
   const swaparooInstance = instances?.['swaparoo'];
   const invitationPurse = usePurse('Invitation');
-  const swaparooInvitations = invitationPurse?.currentAmount.value.filter(
+  const swaparooInvitations = Array.isArray(invitationPurse?.currentAmount.value) ?
+  invitationPurse?.currentAmount.value.filter(
+    // @ts-expect-error cast
     ({ instance, description }: { instance: unknown; description: string }) =>
       instance === swaparooInstance && description.startsWith('matchOffer'),
-  ) as Array<unknown>[] | undefined;
+  ): []
 
   return (
     <div className="w-80">
diff --git a/ui/src/providers/Contract.tsx b/ui/src/providers/Contract.tsx
index 3ceaf8f9..b0864327 100644
--- a/ui/src/providers/Contract.tsx
+++ b/ui/src/providers/Contract.tsx
@@ -19,7 +19,7 @@ const watchContract = (watcher: ChainStorageWatcher) => {
     },
   );
 
-  watcher.watchLatest<Array<[string, unknown]>>(
+  watcher.watchLatest<Array<[string, Brand]>>(
     [Kind.Data, 'published.agoricNames.brand'],
     brands => {
       console.log('Got brands', brands);
diff --git a/ui/src/store/contract.ts b/ui/src/store/contract.ts
index c3e9cc87..3b53bc30 100644
--- a/ui/src/store/contract.ts
+++ b/ui/src/store/contract.ts
@@ -2,7 +2,7 @@ import { create } from 'zustand';
 
 interface ContractState {
   instances?: Record<string, unknown>;
-  brands?: Record<string, unknown>;
+  brands?: Record<string, Brand>;
 }
 
 export const useContractStore = create<ContractState>(() => ({}));