fix(tui): handle undefined agent during login/bootstrap transition

packages/opencode/src/cli/cmd/tui/component/dialog-agent.tsx

@@ -20,7 +20,7 @@ export function DialogAgent() {
   return (
     <DialogSelect
       title="Select agent"
-      current={local.agent.current().name}
+      current={local.agent.current()?.name ?? ""}
       options={options()}
       onSelect={(option) => {
         local.agent.set(option.value)

packages/opencode/src/cli/cmd/tui/component/prompt/index.tsx

@@ -530,7 +530,7 @@ export function Prompt(props: PromptProps) {
     if (store.mode === "shell") {
       sdk.client.session.shell({
         sessionID,
-        agent: local.agent.current().name,
+        agent: local.agent.current()?.name ?? "",
         model: {
           providerID: selectedModel.providerID,
           modelID: selectedModel.modelID,
@@ -551,7 +551,7 @@ export function Prompt(props: PromptProps) {
         sessionID,
         command: command.slice(1),
         arguments: args.join(" "),
-        agent: local.agent.current().name,
+        agent: local.agent.current()?.name ?? "",
         model: `${selectedModel.providerID}/${selectedModel.modelID}`,
         messageID,
         variant,
@@ -567,7 +567,7 @@ export function Prompt(props: PromptProps) {
         sessionID,
         ...selectedModel,
         messageID,
-        agent: local.agent.current().name,
+        agent: local.agent.current()?.name ?? "",
         model: selectedModel,
         variant,
         parts: [
@@ -687,7 +687,7 @@ export function Prompt(props: PromptProps) {
   const highlight = createMemo(() => {
     if (keybind.leader) return theme.border
     if (store.mode === "shell") return theme.primary
-    return local.agent.color(local.agent.current().name)
+    return local.agent.color(local.agent.current()?.name ?? "")
   })
 
   const showVariant = createMemo(() => {
@@ -698,7 +698,7 @@ export function Prompt(props: PromptProps) {
   })
 
   const spinnerDef = createMemo(() => {
-    const color = local.agent.color(local.agent.current().name)
+    const color = local.agent.color(local.agent.current()?.name ?? "")
     return {
       frames: createFrames({
         color,
@@ -932,7 +932,7 @@ export function Prompt(props: PromptProps) {
             />
             <box flexDirection="row" flexShrink={0} paddingTop={1} gap={1}>
               <text fg={highlight()}>
-                {store.mode === "shell" ? "Shell" : Locale.titlecase(local.agent.current().name)}{" "}
+                {store.mode === "shell" ? "Shell" : Locale.titlecase(local.agent.current()?.name ?? "")}{" "}
               </text>
               <Show when={store.mode === "normal"}>
                 <box flexDirection="row" gap={1}>

packages/opencode/src/cli/cmd/tui/context/local.tsx

@@ -38,8 +38,20 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
       const [agentStore, setAgentStore] = createStore<{
         current: string
       }>({
-        current: agents()[0].name,
+        // Use empty string as safe initial value - will be updated reactively when agents load
+        current: agents()[0]?.name ?? "",
       })
+
+      // Reactively update current agent when agents list changes (e.g., after login/bootstrap)
+      createEffect(() => {
+        const list = agents()
+        if (list.length === 0) return
+        // If current is empty or no longer valid, set to first agent
+        if (!agentStore.current || !list.some((x) => x.name === agentStore.current)) {
+          setAgentStore("current", list[0].name)
+        }
+      })
+
       const { theme } = useTheme()
       const colors = createMemo(() => [
         theme.secondary,
@@ -54,7 +66,9 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
           return agents()
         },
         current() {
-          return agents().find((x) => x.name === agentStore.current)!
+          const found = agents().find((x) => x.name === agentStore.current)
+          // Return first agent as fallback if current not found (during loading/transition)
+          return found ?? agents()[0]
         },
         set(name: string) {
           if (!agents().some((x) => x.name === name))
@@ -67,11 +81,13 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
         },
         move(direction: 1 | -1) {
           batch(() => {
-            let next = agents().findIndex((x) => x.name === agentStore.current) + direction
-            if (next < 0) next = agents().length - 1
-            if (next >= agents().length) next = 0
-            const value = agents()[next]
-            setAgentStore("current", value.name)
+            const list = agents()
+            if (list.length === 0) return
+            let next = list.findIndex((x) => x.name === agentStore.current) + direction
+            if (next < 0) next = list.length - 1
+            if (next >= list.length) next = 0
+            const value = list[next]
+            if (value) setAgentStore("current", value.name)
           })
         },
         color(name: string) {
@@ -179,6 +195,7 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
 
       const currentModel = createMemo(() => {
         const a = agent.current()
+        if (!a) return fallbackModel() ?? undefined
         return (
           getFirstValidModel(
             () => modelStore.model[a.name],
@@ -227,7 +244,9 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
           if (next >= recent.length) next = 0
           const val = recent[next]
           if (!val) return
-          setModelStore("model", agent.current().name, { ...val })
+          const currentAgent = agent.current()
+          if (!currentAgent) return
+          setModelStore("model", currentAgent.name, { ...val })
         },
         cycleFavorite(direction: 1 | -1) {
           const favorites = modelStore.favorite.filter((item) => isModelValid(item))
@@ -253,7 +272,9 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
           }
           const next = favorites[index]
           if (!next) return
-          setModelStore("model", agent.current().name, { ...next })
+          const currentAgent = agent.current()
+          if (!currentAgent) return
+          setModelStore("model", currentAgent.name, { ...next })
           const uniq = uniqueBy([next, ...modelStore.recent], (x) => `${x.providerID}/${x.modelID}`)
           if (uniq.length > 10) uniq.pop()
           setModelStore(
@@ -272,7 +293,9 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
               })
               return
             }
-            setModelStore("model", agent.current().name, model)
+            const currentAgent = agent.current()
+            if (!currentAgent) return
+            setModelStore("model", currentAgent.name, model)
             if (options?.recent) {
               const uniq = uniqueBy([model, ...modelStore.recent], (x) => `${x.providerID}/${x.modelID}`)
               if (uniq.length > 10) uniq.pop()
@@ -368,6 +391,7 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
     // Automatically update model when agent changes
     createEffect(() => {
       const value = agent.current()
+      if (!value) return
       if (value.model) {
         if (isModelValid(value.model))
           model.set({