From 41ab501b163e09c83f9c83d4abb87f17468e9caa Mon Sep 17 00:00:00 2001
From: cevr <seeve.c@gmail.com>
Date: Tue, 3 Nov 2026 22:35:56 -0500
Subject: [PATCH 1/6] feat(plugin): add transcript, header and layout hook
 points

Publish slots for the session header, transcript start, user messages,
assistant footers and text, reasoning and tool parts, add ui.layout for
row gaps, inset and composer chrome, and let builtins start disabled.
---
 packages/plugin/src/tui/context.ts          | 46 +++++++++++
 packages/tui/src/component/prompt/index.tsx | 33 ++++++--
 packages/tui/src/plugin/api.tsx             | 14 +++-
 packages/tui/src/plugin/builtins.ts         |  4 +
 packages/tui/src/plugin/context.tsx         | 23 ++++--
 packages/tui/src/routes/session/index.tsx   | 87 +++++++++++++++++----
 6 files changed, 177 insertions(+), 30 deletions(-)

diff --git a/packages/plugin/src/tui/context.ts b/packages/plugin/src/tui/context.ts
index fe641b39d5e9..d988058f876b 100644
--- a/packages/plugin/src/tui/context.ts
+++ b/packages/plugin/src/tui/context.ts
@@ -162,6 +162,17 @@ type PromptFooterInput = {
   readonly showDetails: boolean
 }
 
+/** One message of a session transcript. */
+export interface SessionMessageInput {
+  readonly sessionID: string
+  readonly messageID: string
+}
+
+/** One part of an assistant message; read it with data.session.message.get. */
+export interface SessionPartInput extends SessionMessageInput {
+  readonly partID: string
+}
+
 export type PanelPresentation = "panel" | "fullscreen"
 
 /** Client-local state of the selected session panel. The host owns its layout and input scope. */
@@ -196,6 +207,18 @@ export interface SlotMap {
   readonly "prompt.footer.status": PromptFooterInput
   readonly "prompt.footer.file": PromptFooterInput
   readonly "session.composer.top": { readonly sessionID: string }
+  /** Above the transcript, full width. Empty by default. */
+  readonly "session.header": { readonly sessionID: string }
+  /** First child of the transcript scroll area. Empty by default. */
+  readonly "session.transcript.start": { readonly sessionID: string }
+  /** A user prompt in the transcript. */
+  readonly "session.message.user": SessionMessageInput
+  /** The agent, model and duration line closing an assistant turn. */
+  readonly "session.message.assistant.footer": SessionMessageInput
+  readonly "session.part.text": SessionPartInput
+  readonly "session.part.reasoning": SessionPartInput
+  /** One tool call; `tool` is the canonical tool name (shell, patch, subagent, read, ...). */
+  readonly "session.part.tool": SessionPartInput & { readonly tool: string }
   readonly "session.panel": PanelInput
   readonly "sidebar.content": { readonly sessionID: string }
   readonly "sidebar.footer": { readonly sessionID: string }
@@ -487,6 +510,27 @@ export interface Keymap {
   }
 }
 
+/** The kind of one transcript row, as layout rules see it. */
+export type TranscriptRowKind = "user" | "text" | "reasoning" | "tool" | "group" | "footer" | "other"
+
+/**
+ * Host layout knobs a plugin may set. Every field is optional; an unset field
+ * keeps the host default. When several active plugins set one field, the
+ * last-enabled plugin wins.
+ */
+export interface Layout {
+  /** Blank rows above a transcript row. The host default is 1. */
+  readonly rowGap?: (row: { readonly kind: TranscriptRowKind; readonly previous?: TranscriptRowKind }) => number
+  /** Horizontal padding of the transcript and the dock, in cells. The host default is 2. */
+  readonly inset?: number
+  /**
+   * The composer's chrome. "bar" is the host default: a left accent bar and a
+   * metadata row. "band" is a full-width band on raised.base with a blank row
+   * above and below the editor and the given prefix before it.
+   */
+  readonly composer?: { readonly chrome: "bar" } | { readonly chrome: "band"; readonly prefix?: string }
+}
+
 export interface UI {
   readonly dialog: Dialog
   readonly toast: Toast
@@ -539,6 +583,8 @@ export interface UI {
   }
   /** Claims a place in the slot tree; see SlotClaim. */
   readonly slot: (claim: SlotClaim) => () => void
+  /** Sets host layout knobs until the returned cleanup runs; see Layout. */
+  readonly layout: (layout: Layout) => () => void
 }
 
 export interface Context {
diff --git a/packages/tui/src/component/prompt/index.tsx b/packages/tui/src/component/prompt/index.tsx
index 075f037dcc55..a4d54ba1eccd 100644
--- a/packages/tui/src/component/prompt/index.tsx
+++ b/packages/tui/src/component/prompt/index.tsx
@@ -58,6 +58,7 @@ import { Keymap, type KeymapCommand } from "../../context/keymap"
 import { useInteractivity } from "../../context/interactivity"
 import { abbreviateHome } from "../../runtime"
 import { Slot } from "../../plugin/render"
+import { usePlugin } from "../../plugin/context"
 import type { SessionInbox } from "@opencode/schema/session-inbox"
 import {
   deduplicatePromptImages,
@@ -1675,14 +1676,23 @@ export function Prompt(props: PromptProps) {
   })
   const maxHeight = createMemo(() => Math.max(6, Math.floor(dimensions().height / 3)))
 
-  const promptBg = createMemo(() => theme.decrease(theme.background.raised.base))
+  const plugins = usePlugin()
+  // "band" chrome: no accent bar or metadata row; the editor sits on a
+  // raised band with a blank row above and below and an optional prefix.
+  const band = createMemo(() => {
+    const composer = plugins.layout().composer
+    return composer?.chrome === "band" ? { prefix: composer.prefix } : undefined
+  })
+  const promptBg = createMemo(() =>
+    band() ? theme.background.raised.base : theme.decrease(theme.background.raised.base),
+  )
 
   return (
     <>
       <box ref={(r: BoxRenderable) => (anchor = r)} visible={props.visible !== false} width="100%">
         <box
           width="100%"
-          border={["left"]}
+          border={band() ? undefined : ["left"]}
           borderColor={borderHighlight()}
           customBorderChars={{
             ...SplitBorder.customBorderChars,
@@ -1690,9 +1700,10 @@ export function Prompt(props: PromptProps) {
           }}
         >
           <box
-            paddingLeft={dimensions().width < 44 ? 1 : 2}
+            paddingLeft={band() ? 1 : dimensions().width < 44 ? 1 : 2}
             paddingRight={dimensions().width < 44 ? 1 : 2}
             paddingTop={1}
+            paddingBottom={band() ? 1 : 0}
             flexShrink={0}
             backgroundColor={promptBg()}
             flexGrow={1}
@@ -1766,8 +1777,11 @@ export function Prompt(props: PromptProps) {
                 </Show>
               </box>
             </Show>
+            <box flexDirection="row" width="100%">
+            <Show when={band()?.prefix}>{(prefix) => <text fg={theme.text.base}>{prefix()}</text>}</Show>
             <textarea
-              width="100%"
+              flexGrow={1}
+              flexShrink={1}
               placeholder={placeholderText()}
               placeholderColor={theme.text.muted}
               textColor={muted() ? theme.text.muted : theme.text.base}
@@ -1853,7 +1867,15 @@ export function Prompt(props: PromptProps) {
               cursorColor={disabled() ? theme.background.raised.base : theme.text.base}
               syntaxStyle={syntax()}
             />
-            <box flexDirection="row" flexShrink={0} paddingTop={1} gap={1} justifyContent="space-between">
+            </box>
+            <box
+              flexDirection="row"
+              flexShrink={0}
+              paddingTop={1}
+              gap={1}
+              justifyContent="space-between"
+              visible={!band()}
+            >
               <PromptMetadataRow
                 mode={store.mode}
                 agent={agentLabel()}
@@ -1873,6 +1895,7 @@ export function Prompt(props: PromptProps) {
         </box>
         <box
           height={1}
+          visible={!band()}
           border={["left"]}
           borderColor={borderHighlight()}
           customBorderChars={{
diff --git a/packages/tui/src/plugin/api.tsx b/packages/tui/src/plugin/api.tsx
index 35a4eac6e563..3e9988a29043 100644
--- a/packages/tui/src/plugin/api.tsx
+++ b/packages/tui/src/plugin/api.tsx
@@ -4,6 +4,7 @@ import type {
   Context,
   Dialog,
   DialogSelectOptions,
+  Layout,
   Page,
   SlotClaim,
   SlotMap,
@@ -51,11 +52,12 @@ const placements = ["prepend", "append", "before", "after", "replace"] as const
 // route/slot registration lands there, but ordering and lifecycle stay owned
 // by the provider.
 export type Registry = {
-  has(kind: "routes" | "slots" | "markdown", name: string): boolean
+  has(kind: "routes" | "slots" | "markdown" | "layout", name: string): boolean
   set(kind: "routes", name: string, page: Page): void
   set(kind: "slots", name: string, claim: RegisteredSlot): void
   set(kind: "markdown", name: string, render: MarkdownCodeBlockRenderer): void
-  remove(kind: "routes" | "slots" | "markdown", name: string): void
+  set(kind: "layout", name: string, layout: Layout): void
+  remove(kind: "routes" | "slots" | "markdown" | "layout", name: string): void
   active(): boolean
 }
 
@@ -99,6 +101,7 @@ export function createPluginContext(input: {
   input.owned.push(async () => host.panel?.release(input.id))
   let context: Context
   let claims = 0
+  let layouts = 0
   // Every dialog and registered render is wrapped so plugin components can
   // reach their own context through usePlugin().
   const provide = (render: () => JSX.Element) => (
@@ -132,7 +135,7 @@ export function createPluginContext(input: {
   }
   // Unregistering after deactivation is a no-op: deactivate already resets
   // the registration's routes and slots wholesale.
-  const registration = (kind: "routes" | "slots" | "markdown", name: string) => {
+  const registration = (kind: "routes" | "slots" | "markdown" | "layout", name: string) => {
     let registered = true
     const unregister = () => {
       if (!registered) return
@@ -310,6 +313,11 @@ export function createPluginContext(input: {
         })
         return registration("slots", key)
       },
+      layout(value: Layout) {
+        const key = `layout#${layouts++}`
+        input.registry.set("layout", key, value)
+        return registration("layout", key)
+      },
     },
   }
   return context
diff --git a/packages/tui/src/plugin/builtins.ts b/packages/tui/src/plugin/builtins.ts
index 3f6a5728efda..a505ac850a6a 100644
--- a/packages/tui/src/plugin/builtins.ts
+++ b/packages/tui/src/plugin/builtins.ts
@@ -14,6 +14,10 @@ import Stats from "../feature-plugins/system/stats"
 import Latex from "@opencode/latex/plugin"
 import Merman from "@opencode/merman/plugin"
 
+// Builtins listed here start disabled; a tui config `plugins` entry naming
+// the id enables them.
+export const optIn: ReadonlySet<string> = new Set<string>()
+
 export const builtins = [
   HomeFooter,
   PromptFooter,
diff --git a/packages/tui/src/plugin/context.tsx b/packages/tui/src/plugin/context.tsx
index 7bcdb4ab4213..68d36775979f 100644
--- a/packages/tui/src/plugin/context.tsx
+++ b/packages/tui/src/plugin/context.tsx
@@ -16,7 +16,7 @@ import {
 import path from "path"
 import { stat } from "fs/promises"
 import { fileURLToPath } from "url"
-import type { Page } from "@opencode/plugin/tui/context"
+import type { Layout, Page } from "@opencode/plugin/tui/context"
 import { Host } from "@opencode/plugin/host"
 import { resolveSlots, type Claim } from "./structure"
 import { createStore, produce, reconcile as reconcileStore, unwrap } from "solid-js/store"
@@ -62,6 +62,8 @@ type Value = {
     readonly resolved: () => ReturnType<typeof resolveSlots<SlotRender>>
   }
   readonly markdown: () => MarkdownOptions["renderNode"]
+  /** Layout knobs merged across active plugins; later-enabled plugins win per field. */
+  readonly layout: () => Layout
   readonly activate: (id: string) => Promise<boolean>
   readonly deactivate: (id: string) => Promise<boolean>
 }
@@ -76,6 +78,7 @@ type Registration = {
   routes: Record<string, Page>
   slots: Record<string, RegisteredSlot>
   markdown: Record<string, MarkdownCodeBlockRenderer>
+  layout: Record<string, Layout>
   cleanups: Dispose[]
 }
 
@@ -145,7 +148,15 @@ export function PluginProvider(props: ParentProps<{ packages: PackageSource; dir
     setStore("registrations", id, "routes", reconcileStore({}))
     setStore("registrations", id, "slots", reconcileStore({}))
     setStore("registrations", id, "markdown", reconcileStore({}))
+    setStore("registrations", id, "layout", reconcileStore({}))
   }
+  const layout = createMemo<Layout>(() =>
+    Object.values(store.registrations).reduce<Layout>(
+      (merged, registration) =>
+        registration.active ? Object.values(registration.layout).reduce((all, item) => ({ ...all, ...item }), merged) : merged,
+      {},
+    ),
+  )
 
   const activate = async (id: string) => {
     const item = store.registrations[id]
@@ -164,9 +175,9 @@ export function PluginProvider(props: ParentProps<{ packages: PackageSource; dir
       registry: {
         has: (kind, name) => Boolean(store.registrations[id]?.[kind][name]),
         set: (
-          kind: "routes" | "slots" | "markdown",
+          kind: "routes" | "slots" | "markdown" | "layout",
           name: string,
-          value: Page | RegisteredSlot | MarkdownCodeBlockRenderer,
+          value: Page | RegisteredSlot | MarkdownCodeBlockRenderer | Layout,
         ) => setStore("registrations", id, kind, name, () => value),
         remove: (kind, name) =>
           setStore(
@@ -310,10 +321,10 @@ export function PluginProvider(props: ParentProps<{ packages: PackageSource; dir
 
     // Resolve: fold entries into one desired generation. A source that fails
     // to import keeps its running previous version and only reports failure.
-    const { builtins } = await import("./builtins")
+    const { builtins, optIn } = await import("./builtins")
     const desired = new Map<string, Desired>()
     for (const plugin of builtins)
-      desired.set(plugin.id, { plugin, source: "builtin", version: "builtin", enabled: true })
+      desired.set(plugin.id, { plugin, source: "builtin", version: "builtin", enabled: !optIn.has(plugin.id) })
     const failures: State[] = []
     for (const source of entries) {
       const entry = source.entry
@@ -608,6 +619,7 @@ export function PluginProvider(props: ParentProps<{ packages: PackageSource; dir
         route: (id, name) => store.registrations[id]?.routes[name]?.render,
         slots: { register: registerSlot, resolved },
         markdown,
+        layout,
         // Manual dialog toggles join the same chain as reconciles so a
         // toggle mid-reload cannot mix registrations across generations.
         activate: (id) => enqueue(() => activate(id)),
@@ -708,6 +720,7 @@ function toRegistration(item: Desired): Registration {
     routes: {},
     slots: {},
     markdown: {},
+    layout: {},
     cleanups: [],
   }
 }
diff --git a/packages/tui/src/routes/session/index.tsx b/packages/tui/src/routes/session/index.tsx
index e470eae06ccc..f8be0b53308d 100644
--- a/packages/tui/src/routes/session/index.tsx
+++ b/packages/tui/src/routes/session/index.tsx
@@ -102,6 +102,7 @@ import { usePathFormatter } from "../../context/path-format"
 import { useLocation } from "../../context/location"
 import { Slot } from "../../plugin/render"
 import { usePlugin } from "../../plugin/context"
+import type { TranscriptRowKind } from "@opencode/plugin/tui/context"
 import {
   cacheReuseDrop,
   completeGroupBoundary,
@@ -159,6 +160,7 @@ export function Session(props: {
   width?: number
 }) {
   const epilogue = useEpilogue()
+  const plugins = usePlugin()
   const clipboard = useClipboard()
   const writeExport = async (file: string, content: string) => {
     await mkdir(path.dirname(file), { recursive: true })
@@ -258,7 +260,9 @@ export function Session(props: {
     enabled: () => props.sidebarVisible && dimensions().width - props.verticalTabsWidth <= 120 && !disabled(),
     commands: [{ bind: "escape,ctrl+c", title: "Close sidebar", group: "Session", run: props.onToggleSidebar }],
   }))
-  const contentWidth = createMemo(() => (props.width ?? dimensions().width - props.verticalTabsWidth) - 4)
+  const contentWidth = createMemo(
+    () => (props.width ?? dimensions().width - props.verticalTabsWidth) - 2 * (plugins.layout().inset ?? 2),
+  )
   const models = createMemo(() => data.location.model.list(location()) ?? [])
 
   const scrollAcceleration = createMemo(() => getScrollAcceleration(config))
@@ -1516,10 +1520,11 @@ export function Session(props: {
           flexGrow={1}
           minHeight={0}
           paddingBottom={1}
-          paddingLeft={dimensions().width < 44 ? 1 : 2}
-          paddingRight={dimensions().width < 44 ? 1 : 2}
+          paddingLeft={plugins.layout().inset ?? (dimensions().width < 44 ? 1 : 2)}
+          paddingRight={plugins.layout().inset ?? (dimensions().width < 44 ? 1 : 2)}
         >
           <Show when={session()}>
+            <Slot path="session.header" input={{ sessionID: route.sessionID }} />
             <box flexGrow={1} minHeight={0} position="relative">
               <scrollbox
                 ref={(r) => {
@@ -1549,10 +1554,12 @@ export function Session(props: {
                   updateAwayFromBottom()
                 }}
               >
+                <Slot path="session.transcript.start" input={{ sessionID: route.sessionID }} />
                 <For each={visibleRows()}>
                   {(row, index) => (
                     <SessionRowView
                       row={row}
+                      previous={visibleRows()[index() - 1]}
                       message={(messageID) => data.session.message.get(route.sessionID, messageID)}
                       boundaryID={boundaries()[index() + hidden()]}
                     />
@@ -1669,18 +1676,44 @@ export function Session(props: {
 
 type SessionRowViewProps = {
   row: SessionRow
+  previous?: SessionRow
   message: (messageID: string) => SessionMessageInfo | undefined
   boundaryID?: string
 }
 
+// The coarse row kind a plugin layout rule sees: one name per visual role.
+function transcriptRowKind(
+  row: SessionRow,
+  message: (messageID: string) => SessionMessageInfo | undefined,
+): TranscriptRowKind {
+  if (row.type === "group") return "group"
+  if (row.type === "assistant-footer") return "footer"
+  if (row.type === "message") return message(row.messageID)?.type === "user" ? "user" : "other"
+  if (row.type !== "part") return "other"
+  const item = message(row.ref.messageID)
+  if (item?.type !== "assistant") return "other"
+  const part = resolvePart(item, row.ref.partID)
+  if (part?.type === "text" || part?.type === "reasoning" || part?.type === "tool") return part.type
+  return "other"
+}
+
 function SessionRowView(props: SessionRowViewProps) {
+  const plugins = usePlugin()
   const [target, setTarget] = createSignal<BoxRenderable>()
   useEntryAnchor({
     entry: () => (props.row.type === "group" ? undefined : props.row),
     node: target,
   })
+  const gap = createMemo(() => {
+    const rule = plugins.layout().rowGap
+    if (!rule) return 1
+    return rule({
+      kind: transcriptRowKind(props.row, props.message),
+      previous: props.previous ? transcriptRowKind(props.previous, props.message) : undefined,
+    })
+  })
   return (
-    <box ref={setTarget} id={sessionRowID(props.row, props.boundaryID)} marginTop={1} flexShrink={0}>
+    <box ref={setTarget} id={sessionRowID(props.row, props.boundaryID)} marginTop={gap()} flexShrink={0}>
       <Switch>
         <Match when={props.row.type === "group" ? props.row : undefined}>
           {(row) => (
@@ -1701,6 +1734,7 @@ function SessionRowView(props: SessionRowViewProps) {
 }
 
 function SessionEntryView(props: { row: SessionEntry; message: SessionRowViewProps["message"]; images?: boolean }) {
+  const ctx = use()
   return (
     <Switch>
       <Match when={props.row.type === "message" ? props.row : undefined}>
@@ -1719,7 +1753,12 @@ function SessionEntryView(props: { row: SessionEntry; message: SessionRowViewPro
           <Show when={props.message(row().messageID)}>
             {(message) => (
               <Show when={message().type === "assistant"}>
-                <AssistantFooter message={message() as SessionMessageAssistant} />
+                <Slot
+                  path="session.message.assistant.footer"
+                  input={{ sessionID: ctx.sessionID, messageID: message().id }}
+                >
+                  <AssistantFooter message={message() as SessionMessageAssistant} />
+                </Slot>
               </Show>
             )}
           </Show>
@@ -1929,10 +1968,13 @@ function BackgroundToolHint(props: { messages: SessionMessageInfo[] }) {
 }
 
 function SessionMessageView(props: { message: SessionMessageInfo }) {
+  const ctx = use()
   return (
     <Switch>
       <Match when={props.message.type === "user"}>
-        <UserMessage message={props.message as SessionMessageUser} />
+        <Slot path="session.message.user" input={{ sessionID: ctx.sessionID, messageID: props.message.id }}>
+          <UserMessage message={props.message as SessionMessageUser} />
+        </Slot>
       </Match>
       <Match when={props.message.type === "shell"}>
         <ShellMessage message={props.message as Extract<SessionMessageInfo, { type: "shell" }>} />
@@ -1983,26 +2025,37 @@ function SessionPartView(props: {
     if (item?.type !== "assistant") return
     return resolvePart(item, props.partRef.partID)
   })
+  const ctx = use()
+  const input = () => ({ sessionID: ctx.sessionID, messageID: props.partRef.messageID, partID: props.partRef.partID })
   return (
     <Show when={part()}>
       {(item) => (
         <Switch>
           <Match when={item().type === "text"}>
-            <TextPart
-              part={item() as SessionMessageAssistantText}
-              message={message() as SessionMessageAssistant}
-              last={false}
-            />
+            <Slot path="session.part.text" input={input()}>
+              <TextPart
+                part={item() as SessionMessageAssistantText}
+                message={message() as SessionMessageAssistant}
+                last={false}
+              />
+            </Slot>
           </Match>
           <Match when={item().type === "reasoning"}>
-            <ReasoningPart
-              part={item() as SessionMessageAssistantReasoning}
-              message={message() as SessionMessageAssistant}
-              last={false}
-            />
+            <Slot path="session.part.reasoning" input={input()}>
+              <ReasoningPart
+                part={item() as SessionMessageAssistantReasoning}
+                message={message() as SessionMessageAssistant}
+                last={false}
+              />
+            </Slot>
           </Match>
           <Match when={item().type === "tool"}>
-            <ToolPart part={item() as SessionMessageAssistantTool} images={props.images} />
+            <Slot
+              path="session.part.tool"
+              input={{ ...input(), tool: canonicalToolName((item() as SessionMessageAssistantTool).name) }}
+            >
+              <ToolPart part={item() as SessionMessageAssistantTool} images={props.images} />
+            </Slot>
           </Match>
         </Switch>
       )}

From 1919478a208c46c37ad1cd4183766fe874cd7bab Mon Sep 17 00:00:00 2001
From: cevr <seeve.c@gmail.com>
Date: Tue, 3 Nov 2026 23:13:43 -0500
Subject: [PATCH 2/6] feat(plugin): read a session's parts, context usage and
 goal

data.session.part.get resolves the part a session.part.* slot receives.
data.session.usage reports the last turn's tokens against the model's
context window. data.session.goal keeps one host-level copy of the goal,
fetched on first read and kept current from goal events; the prompt
footer now reads it too.
---
 packages/plugin/src/tui/context.ts            | 42 +++++++++-
 packages/tui/src/context/data.tsx             | 79 ++++++++++++++++++-
 .../tui/src/feature-plugins/prompt/goal.tsx   | 60 +++-----------
 packages/tui/src/routes/session/rows.ts       |  9 +--
 packages/tui/src/util/session.ts              | 13 ++-
 .../feature-plugins/prompt-footer.test.tsx    | 36 +++------
 6 files changed, 154 insertions(+), 85 deletions(-)

diff --git a/packages/plugin/src/tui/context.ts b/packages/plugin/src/tui/context.ts
index d988058f876b..e683e7da9888 100644
--- a/packages/plugin/src/tui/context.ts
+++ b/packages/plugin/src/tui/context.ts
@@ -17,6 +17,7 @@ import type {
   ProviderInfo,
   ReferenceInfo,
   SessionInfo,
+  SessionMessageAssistant,
   SessionMessageInfo,
   SessionInboxInfo,
   ShellInfo,
@@ -60,6 +61,27 @@ interface LocationCollection<Value> {
 
 type OpenCodeEventMap = { [Type in OpenCodeEvent["type"]]: Extract<OpenCodeEvent, { type: Type }> }
 
+/** One part of an assistant message: text, reasoning or a tool call. */
+export type SessionPart = SessionMessageAssistant["content"][number]
+
+/** How much of its model's context window a session's last turn used. */
+export interface SessionUsage {
+  /** Input, output, reasoning and cache tokens of the last assistant turn with usage. */
+  readonly tokens: number
+  /** The model's context window, when the model is known. */
+  readonly limit?: number
+  /** `tokens` as a rounded percentage of `limit`. */
+  readonly percent?: number
+}
+
+/** The goal `/goal` set on a session. */
+export interface SessionGoal {
+  readonly objective: string
+  readonly status: "active" | "paused" | "complete"
+  /** Why the goal last changed. */
+  readonly reason?: string
+}
+
 export interface Data {
   readonly on: <Type extends OpenCodeEvent["type"]>(
     type: Type,
@@ -73,6 +95,17 @@ export interface Data {
     family(sessionID: string): string[]
     cost(sessionID: string): number
     status(sessionID: string): "idle" | "running"
+    /**
+     * The context window the session's last turn used, up to its revert point.
+     * Undefined until a turn reports usage. Reactive when read in a Solid computation.
+     */
+    usage(sessionID: string): SessionUsage | undefined
+    /**
+     * The session's goal, or undefined when none is set or the server has no
+     * goal plugin. Fetched on first read and kept current from the server.
+     * Reactive when read in a Solid computation.
+     */
+    goal(sessionID: string): SessionGoal | undefined
     readonly pending: {
       list(sessionID: string): SessionInboxInfo[]
       sync(sessionID: string): Promise<void>
@@ -86,6 +119,13 @@ export interface Data {
       sync(sessionID: string): Promise<void>
       invalidate(sessionID: string): void
     }
+    readonly part: {
+      /**
+       * One part of an assistant message, by the `partID` a session.part.*
+       * slot receives. Reactive when read in a Solid computation.
+       */
+      get(sessionID: string, messageID: string, partID: string): SessionPart | undefined
+    }
     readonly permission: {
       list(sessionID: string): PermissionRequest[] | undefined
       sync(sessionID: string): Promise<void>
@@ -168,7 +208,7 @@ export interface SessionMessageInput {
   readonly messageID: string
 }
 
-/** One part of an assistant message; read it with data.session.message.get. */
+/** One part of an assistant message; read it with data.session.part.get. */
 export interface SessionPartInput extends SessionMessageInput {
   readonly partID: string
 }
diff --git a/packages/tui/src/context/data.tsx b/packages/tui/src/context/data.tsx
index 8c7668f9a77a..5942f67ed412 100644
--- a/packages/tui/src/context/data.tsx
+++ b/packages/tui/src/context/data.tsx
@@ -1,9 +1,13 @@
 import { createData } from "@opencode/client/solid"
 import { withMediaRefs, type LocationRef } from "@opencode/client"
 import type { Plugin } from "@opencode/plugin/tui"
+import type { SessionGoal } from "@opencode/plugin/tui/context"
+import { Goal } from "@opencode/schema/goal"
+import { onCleanup } from "solid-js"
 import { createStore } from "solid-js/store"
 import { createSimpleContext } from "./helper"
 import { useClient } from "./client"
+import { contextUsage, resolvePart } from "../util/session"
 
 export { locationKey } from "@opencode/client/solid"
 export type { FormWithLocation } from "@opencode/client/solid"
@@ -19,9 +23,16 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
       connection: client.connection,
       directory: props.directory,
     })
-    data satisfies Plugin.Context["data"]
+    const goal = createGoals({
+      // The client is replaced on reconnect, so each read resolves it anew.
+      fetch: (sessionID) => {
+        const directory = data.session.get(sessionID)?.location.directory
+        return client.api.rpc(Goal.Definition).get({ sessionID }, directory ? { location: { directory } } : undefined)
+      },
+      on: data.on,
+    })
     const [generatingTitles, setGeneratingTitles] = createStore<Record<string, boolean | undefined>>({})
-    return {
+    const value = {
       ...data,
       location: {
         ...data.location,
@@ -32,6 +43,22 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
       },
       session: {
         ...data.session,
+        part: {
+          get(sessionID: string, messageID: string, partID: string) {
+            const message = data.session.message.get(sessionID, messageID)
+            return message?.type === "assistant" ? resolvePart(message, partID) : undefined
+          },
+        },
+        usage(sessionID: string) {
+          const session = data.session.get(sessionID)
+          if (!session) return
+          return contextUsage(
+            data.session.message.list(sessionID),
+            data.location.model.list(session.location),
+            session.revert?.messageID,
+          )
+        },
+        goal: goal.get,
         title: {
           pending: (sessionID: string) => generatingTitles[sessionID] === true,
           async generate(sessionID: string) {
@@ -49,5 +76,53 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
         },
       },
     }
+    value satisfies Plugin.Context["data"]
+    return value
   },
 })
+
+/**
+ * Goals by session, from the goal plugin's RPC: fetched on a session's first read and again when the server
+ * reconnects, since changes published meanwhile were missed, and kept current from its `changed` events.
+ */
+function createGoals(input: {
+  fetch: (sessionID: string) => Promise<Goal.State | null>
+  on: ReturnType<typeof createData>["on"]
+}) {
+  // null records a session known to have no goal; a missing key is not loaded yet.
+  const [goals, setGoals] = createStore<Record<string, SessionGoal | null>>({})
+  // A change that arrives while a fetch is in flight is newer than its reply, so each change or fetch takes a turn.
+  const turns = new Map<string, number>()
+  const turn = (sessionID: string) => {
+    const next = (turns.get(sessionID) ?? 0) + 1
+    turns.set(sessionID, next)
+    return next
+  }
+  const set = (sessionID: string, goal: Goal.State | null | undefined) =>
+    setGoals(sessionID, goal ? { objective: goal.objective, status: goal.status, reason: goal.reason } : null)
+  const load = (sessionID: string) => {
+    const current = turn(sessionID)
+    // A server without the goal plugin answers with an error, and the session shows no goal.
+    void input.fetch(sessionID).then(
+        (goal) => {
+          if (turns.get(sessionID) === current) set(sessionID, goal)
+        },
+        () => undefined,
+      )
+  }
+  onCleanup(
+    input.on(`rpc.${Goal.Definition.id}.changed`, (event) => {
+      const payload = event.data as { sessionID: string; goal: Goal.State | null }
+      if (!turns.has(payload.sessionID)) return
+      turn(payload.sessionID)
+      set(payload.sessionID, payload.goal)
+    }),
+  )
+  onCleanup(input.on("server.connected", () => turns.forEach((_, sessionID) => load(sessionID))))
+  return {
+    get(sessionID: string) {
+      if (!turns.has(sessionID)) load(sessionID)
+      return goals[sessionID] ?? undefined
+    },
+  }
+}
diff --git a/packages/tui/src/feature-plugins/prompt/goal.tsx b/packages/tui/src/feature-plugins/prompt/goal.tsx
index ad5c0aa827ab..52b2604f0f19 100644
--- a/packages/tui/src/feature-plugins/prompt/goal.tsx
+++ b/packages/tui/src/feature-plugins/prompt/goal.tsx
@@ -1,59 +1,25 @@
 import type { Plugin } from "@opencode/plugin/tui"
-import { Goal } from "@opencode/schema/goal"
-import { createEffect, createMemo, createSignal, on, onCleanup, Show, type Accessor } from "solid-js"
+import type { SessionGoal } from "@opencode/plugin/tui/context"
+import { createMemo, createSignal, Show, type Accessor } from "solid-js"
 import { Keymap } from "../../context/keymap"
 import { useTheme } from "../../context/theme"
 import { DialogFooter, DialogHeader, DialogLayout, type DialogFooterAction } from "../../ui/dialog"
 
-/**
- * The goal `/goal` set on a Session, from the goal plugin's RPC: fetched when the Session changes or the server
- * reconnects, since changes published meanwhile were missed, and kept current from its `changed` events.
- */
+/** The goal `/goal` set on a Session, kept current by the host. */
 export function createGoal(context: Plugin.Context, sessionID: Accessor<string | undefined>) {
-  const [goal, setGoal] = createSignal<Goal.State>()
-  const rpc = context.client.rpc(Goal.Definition)
-  // A change that arrives while a fetch is in flight is newer than its reply, so each change or fetch takes a turn.
-  const turn = { value: 0 }
-  const load = (id: string) => {
-    const current = ++turn.value
-    const directory = context.data.session.get(id)?.location.directory
-    // A server without the goal plugin answers with an error, and the Session shows no goal.
-    void rpc.get({ sessionID: id }, directory ? { location: { directory } } : undefined).then(
-      (next) => {
-        if (current === turn.value && sessionID() === id) setGoal(next ?? undefined)
-      },
-      () => undefined,
-    )
-  }
-  onCleanup(
-    rpc.events.on("changed", (event) => {
-      if (event.data.sessionID !== sessionID()) return
-      turn.value++
-      setGoal(event.data.goal ?? undefined)
-    }),
-  )
-  onCleanup(
-    context.data.on("server.connected", () => {
-      const id = sessionID()
-      if (id) load(id)
-    }),
-  )
-  createEffect(
-    on(sessionID, (id) => {
-      setGoal(undefined)
-      if (id) load(id)
-    }),
-  )
-  return goal
+  return createMemo(() => {
+    const id = sessionID()
+    return id ? context.data.session.goal(id) : undefined
+  })
 }
 
-function goalColor(theme: Plugin.Context["theme"], goal: Goal.State) {
+function goalColor(theme: Plugin.Context["theme"], goal: SessionGoal) {
   if (goal.status === "paused") return theme.text.feedback.warning.base
   if (goal.status === "complete") return theme.text.feedback.success.base
   return theme.text.muted
 }
 
-function goalLabel(goal: Goal.State) {
+function goalLabel(goal: SessionGoal) {
   if (goal.status === "paused") return "goal paused"
   if (goal.status === "complete") return "goal met"
   return "goal"
@@ -66,10 +32,10 @@ function goalLabel(goal: Goal.State) {
 export function GoalStatus(props: {
   context: Plugin.Context
   sessionID: string
-  goal: Accessor<Goal.State | undefined>
+  goal: Accessor<SessionGoal | undefined>
 }) {
   const [hovered, setHovered] = createSignal(false)
-  const color = (current: Goal.State) =>
+  const color = (current: SessionGoal) =>
     hovered() ? props.context.theme.text.base : goalColor(props.context.theme, current)
 
   return (
@@ -91,7 +57,7 @@ export function GoalStatus(props: {
 }
 
 /** Opens the goal dialog for a Session, or explains how to start one. */
-function showGoal(context: Plugin.Context, sessionID: string, goal: Accessor<Goal.State | undefined>) {
+function showGoal(context: Plugin.Context, sessionID: string, goal: Accessor<SessionGoal | undefined>) {
   if (!goal()) {
     context.ui.toast.show({ message: "No goal is set. Start one with /goal <objective>.", variant: "info" })
     return
@@ -102,7 +68,7 @@ function showGoal(context: Plugin.Context, sessionID: string, goal: Accessor<Goa
 function GoalDialog(props: {
   context: Plugin.Context
   sessionID: string
-  goal: Accessor<Goal.State | undefined>
+  goal: Accessor<SessionGoal | undefined>
 }) {
   const theme = useTheme().surface("dialog")
   const goal = props.goal
diff --git a/packages/tui/src/routes/session/rows.ts b/packages/tui/src/routes/session/rows.ts
index ed966402fc45..3e1dca6a1d8f 100644
--- a/packages/tui/src/routes/session/rows.ts
+++ b/packages/tui/src/routes/session/rows.ts
@@ -483,11 +483,4 @@ function rowBoundaryMessageID(row: SessionRow, messages: Map<string, SessionMess
   if (message?.type === "assistant") return message.id
 }
 
-export function resolvePart(message: SessionMessageAssistant, partID: string) {
-  const tool = message.content.find((part) => part.type === "tool" && part.id === partID)
-  if (tool) return tool
-  const match = /^(text|reasoning):(\d+)$/.exec(partID)
-  if (!match) return
-  const ordinal = Number(match[2])
-  return message.content.filter((part) => part.type === match[1])[ordinal]
-}
+export { resolvePart } from "../../util/session"
diff --git a/packages/tui/src/util/session.ts b/packages/tui/src/util/session.ts
index c7213e2205ed..47ccd07ec928 100644
--- a/packages/tui/src/util/session.ts
+++ b/packages/tui/src/util/session.ts
@@ -1,4 +1,4 @@
-import type { ModelInfo, SessionMessageInfo } from "@opencode/client"
+import type { ModelInfo, SessionMessageAssistant, SessionMessageInfo } from "@opencode/client"
 import { lastAssistantWithUsage } from "@opencode/client/solid"
 import { Locale } from "./locale"
 
@@ -56,10 +56,21 @@ export function contextUsage(
   const model = models?.find((model) => model.providerID === last.model.providerID && model.id === last.model.id)
   return {
     tokens,
+    limit: model?.limit.context || undefined,
     percent: model?.limit.context ? Math.round((tokens / model.limit.context) * 100) : undefined,
   }
 }
 
+/** One part of an assistant message: a tool call by its call ID, text and reasoning by ordinal (`text:2`). */
+export function resolvePart(message: SessionMessageAssistant, partID: string) {
+  const tool = message.content.find((part) => part.type === "tool" && part.id === partID)
+  if (tool) return tool
+  const match = /^(text|reasoning):(\d+)$/.exec(partID)
+  if (!match) return
+  const ordinal = Number(match[2])
+  return message.content.filter((part) => part.type === match[1])[ordinal]
+}
+
 export function formatContextUsage(tokens: number, percent?: number) {
   const value = Locale.number(tokens)
   return percent === undefined ? value : `${value} (${percent}%)`
diff --git a/packages/tui/test/feature-plugins/prompt-footer.test.tsx b/packages/tui/test/feature-plugins/prompt-footer.test.tsx
index f651f3070181..bd5281422d06 100644
--- a/packages/tui/test/feature-plugins/prompt-footer.test.tsx
+++ b/packages/tui/test/feature-plugins/prompt-footer.test.tsx
@@ -23,10 +23,10 @@ test("prompt footer separates simultaneous subagent, shell, and usage status", a
         id === "session.child.first" ? ["ctrl+j"] : id === "command.palette.show" ? ["ctrl+p"] : [],
       dispatch: (id: string) => dispatched.push(id),
     },
-    client: { rpc: () => ({ get: () => Promise.resolve(null), events: { on: () => () => {} } }) },
     data: {
       on: () => () => {},
       session: {
+        goal: () => undefined,
         family: () => ["session", "child"],
         status: (id: string) => (id === "child" ? "running" : "idle"),
         get: () => ({ id: "session", location: { directory: "/workspace" } }),
@@ -83,10 +83,10 @@ test("prompt footer can hide details", async () => {
         return []
       },
     },
-    client: { rpc: () => ({ get: () => Promise.resolve(null), events: { on: () => () => {} } }) },
     data: {
       on: () => () => {},
       session: {
+        goal: () => undefined,
         family: () => ["session"],
         status: () => "running",
         get: () => ({ id: "session", location: { directory: "/workspace" } }),
@@ -145,17 +145,9 @@ test("prompt footer can hide details", async () => {
 test("prompt footer shows the session's goal without its objective and opens it on click", async () => {
   const muted = RGBA.fromInts(100, 100, 100)
   const warning = RGBA.fromInts(200, 200, 0)
-  const goal = {
-    id: "goal",
-    objective: "Make the test suite pass",
-    status: "active",
-    rounds: 3,
-    maxRounds: 50,
-    boot: "boot",
-    updatedAt: 0,
-  }
-  const fetched = Promise.resolve(goal)
-  const changed: ((event: { data: { sessionID: string; goal: unknown } }) => void)[] = []
+  const goal = { objective: "Make the test suite pass", status: "active" as const }
+  // The host keeps each Session's goal current; the footer only reads it.
+  const [goals, setGoals] = createSignal<Record<string, unknown>>({ session: goal })
   const dialogs: unknown[] = []
   const context = {
     location: { directory: "/workspace" },
@@ -168,15 +160,10 @@ test("prompt footer shows the session's goal without its objective and opens it
     },
     keymap: { shortcuts: () => [] },
     ui: { dialog: { show: (render: unknown) => dialogs.push(render) }, toast: { show: () => {} } },
-    client: {
-      rpc: () => ({
-        get: () => fetched,
-        events: { on: (_name: string, handler: (typeof changed)[number]) => (changed.push(handler), () => {}) },
-      }),
-    },
     data: {
       on: () => () => {},
       session: {
+        goal: (sessionID: string) => goals()[sessionID],
         family: () => ["session"],
         status: () => "idle",
         get: () => ({ id: "session", location: { directory: "/workspace" } }),
@@ -193,8 +180,6 @@ test("prompt footer shows the session's goal without its objective and opens it
   )
 
   try {
-    // The footer fetches the goal from the goal plugin's RPC.
-    await fetched
     await app.renderOnce()
     const frame = app.captureCharFrame()
     expect(frame).toContain("◎ goal")
@@ -207,16 +192,15 @@ test("prompt footer shows the session's goal without its objective and opens it
     expect(dialogs).toHaveLength(1)
     await app.mockMouse.moveTo(70, 1)
 
-    // Then it follows the plugin's changes for this Session only.
-    const change = (sessionID: string, next: unknown) =>
-      changed.forEach((handler) => handler({ data: { sessionID, goal: next } }))
+    // Then it follows the goal of this Session only.
+    const change = (sessionID: string, next: unknown) => setGoals((all) => ({ ...all, [sessionID]: next }))
     change("session", { ...goal, status: "paused", reason: "Stopped by the user" })
-    change("other", null)
+    change("other", undefined)
     await app.renderOnce()
     expect(app.captureCharFrame()).toContain("◎ goal paused")
     expect(findText(app.renderer.root, "◎ goal paused")?.fg.toInts()).toEqual(warning.toInts())
 
-    change("session", null)
+    change("session", undefined)
     await app.renderOnce()
     expect(app.captureCharFrame()).not.toContain("goal")
   } finally {

From 08f56783ccd2d39dabbecb9fefdcabeef675ca20 Mon Sep 17 00:00:00 2001
From: cevr <seeve.c@gmail.com>
Date: Tue, 3 Nov 2026 23:13:45 -0500
Subject: [PATCH 3/6] feat(plugin): render one tool, host markdown and
 transcript defaults

ui.tool(name, render) renders every call of one tool inside the plugin's
error boundary; a session.part.tool slot replace still wins over it.
ui.Markdown renders with the host's syntax style, code-block renderers
and the user's markdown mode. layout({ transcript }) sets grouping and
thinking defaults, which the user's session config overrides.
---
 packages/plugin/src/tui/context.ts        | 35 ++++++++++++++++-
 packages/tui/src/plugin/api.tsx           | 17 +++++++--
 packages/tui/src/plugin/context.tsx       | 46 ++++++++++++++++++-----
 packages/tui/src/plugin/render.tsx        | 43 ++++++++++++++++++++-
 packages/tui/src/routes/session/index.tsx | 24 ++++++++----
 5 files changed, 143 insertions(+), 22 deletions(-)

diff --git a/packages/plugin/src/tui/context.ts b/packages/plugin/src/tui/context.ts
index e683e7da9888..754021c2d0b4 100644
--- a/packages/plugin/src/tui/context.ts
+++ b/packages/plugin/src/tui/context.ts
@@ -25,7 +25,7 @@ import type {
   VcsInfo,
 } from "@opencode/client"
 import type { ResolvedTheme } from "@opencode/theme/tui"
-import type { CliRenderer, KeyEvent, MarkdownCodeBlockRenderer, Renderable } from "@opentui/core"
+import type { CliRenderer, KeyEvent, MarkdownCodeBlockRenderer, Renderable, RGBA } from "@opentui/core"
 import type { JSX } from "@opentui/solid"
 import type { Store } from "solid-js/store"
 
@@ -569,6 +569,30 @@ export interface Layout {
    * above and below the editor and the given prefix before it.
    */
   readonly composer?: { readonly chrome: "bar" } | { readonly chrome: "band"; readonly prefix?: string }
+  /**
+   * Transcript defaults for users who have not chosen. The user's `session`
+   * config wins over them. Fields merge across plugins one by one.
+   */
+  readonly transcript?: {
+    /** "auto" groups related tool calls into one row; "none" shows each call. The host default is "auto". */
+    readonly grouping?: "auto" | "none"
+    /** Whether reasoning shows in full. The host default is "hide". */
+    readonly thinking?: "show" | "hide"
+  }
+}
+
+/** Renders one tool call in the transcript. */
+export type ToolRender = (input: SessionPartInput & { readonly tool: string }) => JSX.Element
+
+/** Host markdown, styled with the current theme's syntax and every registered code-block renderer. */
+export type MarkdownProps = {
+  readonly content: string
+  /** True while the text may still grow, so a trailing block is not finalized. */
+  readonly streaming?: boolean
+  /** Text colour. The theme's markdown text by default. */
+  readonly fg?: RGBA
+  /** Background. The theme's base background by default. */
+  readonly bg?: RGBA
 }
 
 export interface UI {
@@ -625,6 +649,15 @@ export interface UI {
   readonly slot: (claim: SlotClaim) => () => void
   /** Sets host layout knobs until the returned cleanup runs; see Layout. */
   readonly layout: (layout: Layout) => () => void
+  /**
+   * Renders every call of one tool, by its canonical name (shell, patch,
+   * subagent, read, ...), until the returned cleanup runs. When several
+   * active plugins render one tool, the last-enabled one wins. A slot claim
+   * that replaces session.part.tool still wins over it.
+   */
+  readonly tool: (name: string, render: ToolRender) => () => void
+  /** The host's markdown renderer, for text that should read like the transcript. */
+  readonly Markdown: (props: MarkdownProps) => JSX.Element
 }
 
 export interface Context {
diff --git a/packages/tui/src/plugin/api.tsx b/packages/tui/src/plugin/api.tsx
index 3e9988a29043..80956d32f3be 100644
--- a/packages/tui/src/plugin/api.tsx
+++ b/packages/tui/src/plugin/api.tsx
@@ -10,6 +10,7 @@ import type {
   SlotMap,
   SlotPath,
   Toast,
+  ToolRender,
 } from "@opencode/plugin/tui/context"
 import type { Placement, PlacementKind } from "./structure"
 import { infoStringToFiletype, type MarkdownCodeBlockRenderer } from "@opentui/core"
@@ -33,6 +34,7 @@ import { useSessionTabs } from "../context/session-tabs"
 import { useOptionalPanel } from "../context/panel"
 import { useLocal } from "../context/local"
 import { abbreviateHome } from "../util/path-format"
+import { PluginMarkdown } from "./render"
 
 export type Dispose = () => Promise<void>
 
@@ -51,13 +53,16 @@ const placements = ["prepend", "append", "before", "after", "replace"] as const
 // The provider's registration store, narrowed to what a plugin context needs:
 // route/slot registration lands there, but ordering and lifecycle stay owned
 // by the provider.
+export type RegistryKind = "routes" | "slots" | "markdown" | "layout" | "tools"
+
 export type Registry = {
-  has(kind: "routes" | "slots" | "markdown" | "layout", name: string): boolean
+  has(kind: RegistryKind, name: string): boolean
   set(kind: "routes", name: string, page: Page): void
   set(kind: "slots", name: string, claim: RegisteredSlot): void
   set(kind: "markdown", name: string, render: MarkdownCodeBlockRenderer): void
   set(kind: "layout", name: string, layout: Layout): void
-  remove(kind: "routes" | "slots" | "markdown" | "layout", name: string): void
+  set(kind: "tools", name: string, render: ToolRender): void
+  remove(kind: RegistryKind, name: string): void
   active(): boolean
 }
 
@@ -135,7 +140,7 @@ export function createPluginContext(input: {
   }
   // Unregistering after deactivation is a no-op: deactivate already resets
   // the registration's routes and slots wholesale.
-  const registration = (kind: "routes" | "slots" | "markdown" | "layout", name: string) => {
+  const registration = (kind: RegistryKind, name: string) => {
     let registered = true
     const unregister = () => {
       if (!registered) return
@@ -318,6 +323,12 @@ export function createPluginContext(input: {
         input.registry.set("layout", key, value)
         return registration("layout", key)
       },
+      tool(name, render) {
+        if (input.registry.has("tools", name)) throw new Error(`Tool renderer already registered: ${name}`)
+        input.registry.set("tools", name, (toolInput) => provide(() => render(toolInput)))
+        return registration("tools", name)
+      },
+      Markdown: PluginMarkdown,
     },
   }
   return context
diff --git a/packages/tui/src/plugin/context.tsx b/packages/tui/src/plugin/context.tsx
index 68d36775979f..6103de240164 100644
--- a/packages/tui/src/plugin/context.tsx
+++ b/packages/tui/src/plugin/context.tsx
@@ -16,7 +16,7 @@ import {
 import path from "path"
 import { stat } from "fs/promises"
 import { fileURLToPath } from "url"
-import type { Layout, Page } from "@opencode/plugin/tui/context"
+import type { Layout, Page, ToolRender } from "@opencode/plugin/tui/context"
 import { Host } from "@opencode/plugin/host"
 import { resolveSlots, type Claim } from "./structure"
 import { createStore, produce, reconcile as reconcileStore, unwrap } from "solid-js/store"
@@ -27,7 +27,14 @@ import { useTuiLifecycle } from "../context/runtime"
 import { useClient } from "../context/client"
 import { useData } from "../context/data"
 import { errorMessage } from "../util/error"
-import { createPluginContext, usePluginHost, type Dispose, type RegisteredSlot, type SlotRender } from "./api"
+import {
+  createPluginContext,
+  usePluginHost,
+  type Dispose,
+  type RegisteredSlot,
+  type RegistryKind,
+  type SlotRender,
+} from "./api"
 import { createSourceWatcher } from "./watch"
 import { discoverPluginTargets, localSource, mergePluginTargets } from "./discovery"
 import { createPluginSources } from "./source"
@@ -64,6 +71,8 @@ type Value = {
   readonly markdown: () => MarkdownOptions["renderNode"]
   /** Layout knobs merged across active plugins; later-enabled plugins win per field. */
   readonly layout: () => Layout
+  /** The renderer for one canonical tool name; the last-enabled active plugin that registered one wins. */
+  readonly tool: (name: string) => { readonly plugin: string; readonly render: ToolRender } | undefined
   readonly activate: (id: string) => Promise<boolean>
   readonly deactivate: (id: string) => Promise<boolean>
 }
@@ -79,6 +88,7 @@ type Registration = {
   slots: Record<string, RegisteredSlot>
   markdown: Record<string, MarkdownCodeBlockRenderer>
   layout: Record<string, Layout>
+  tools: Record<string, ToolRender>
   cleanups: Dispose[]
 }
 
@@ -149,14 +159,30 @@ export function PluginProvider(props: ParentProps<{ packages: PackageSource; dir
     setStore("registrations", id, "slots", reconcileStore({}))
     setStore("registrations", id, "markdown", reconcileStore({}))
     setStore("registrations", id, "layout", reconcileStore({}))
+    setStore("registrations", id, "tools", reconcileStore({}))
   }
+  // Registration-store key order is enable order, so later items win.
   const layout = createMemo<Layout>(() =>
-    Object.values(store.registrations).reduce<Layout>(
-      (merged, registration) =>
-        registration.active ? Object.values(registration.layout).reduce((all, item) => ({ ...all, ...item }), merged) : merged,
-      {},
-    ),
+    Object.values(store.registrations)
+      .flatMap((registration) => (registration.active ? Object.values(registration.layout) : []))
+      .reduce<Layout>(
+        (merged, item) => ({
+          ...merged,
+          ...item,
+          // Transcript defaults merge field by field, so two plugins may each set one.
+          transcript: item.transcript ? { ...merged.transcript, ...item.transcript } : merged.transcript,
+        }),
+        {},
+      ),
   )
+  const tools = createMemo(() => {
+    const result = new Map<string, { plugin: string; render: ToolRender }>()
+    for (const [plugin, registration] of Object.entries(store.registrations)) {
+      if (!registration.active) continue
+      for (const [name, render] of Object.entries(registration.tools)) result.set(name, { plugin, render })
+    }
+    return result
+  })
 
   const activate = async (id: string) => {
     const item = store.registrations[id]
@@ -175,9 +201,9 @@ export function PluginProvider(props: ParentProps<{ packages: PackageSource; dir
       registry: {
         has: (kind, name) => Boolean(store.registrations[id]?.[kind][name]),
         set: (
-          kind: "routes" | "slots" | "markdown" | "layout",
+          kind: RegistryKind,
           name: string,
-          value: Page | RegisteredSlot | MarkdownCodeBlockRenderer | Layout,
+          value: Page | RegisteredSlot | MarkdownCodeBlockRenderer | Layout | ToolRender,
         ) => setStore("registrations", id, kind, name, () => value),
         remove: (kind, name) =>
           setStore(
@@ -620,6 +646,7 @@ export function PluginProvider(props: ParentProps<{ packages: PackageSource; dir
         slots: { register: registerSlot, resolved },
         markdown,
         layout,
+        tool: (name) => tools().get(name),
         // Manual dialog toggles join the same chain as reconciles so a
         // toggle mid-reload cannot mix registrations across generations.
         activate: (id) => enqueue(() => activate(id)),
@@ -721,6 +748,7 @@ function toRegistration(item: Desired): Registration {
     slots: {},
     markdown: {},
     layout: {},
+    tools: {},
     cleanups: [],
   }
 }
diff --git a/packages/tui/src/plugin/render.tsx b/packages/tui/src/plugin/render.tsx
index e7e93ee032cb..6ef11f84ae65 100644
--- a/packages/tui/src/plugin/render.tsx
+++ b/packages/tui/src/plugin/render.tsx
@@ -14,10 +14,12 @@ import {
   type ParentProps,
 } from "solid-js"
 import { isShallowEqual } from "remeda"
-import type { SlotMap, SlotPath } from "@opencode/plugin/tui/context"
+import type { MarkdownProps, SlotMap, SlotPath } from "@opencode/plugin/tui/context"
 import type { SlotRender } from "./api"
 import { contains, emptySlotted, type Claim } from "./structure"
+import { useConfig } from "../config"
 import { useRoute } from "../context/route"
+import { useTheme, useThemes } from "../context/theme"
 import { useToast } from "../ui/toast"
 import { errorMessage } from "../util/error"
 import { usePlugin } from "./context"
@@ -156,3 +158,42 @@ export function Slot<Path extends SlotPath>(props: SlotProps<Path>) {
     </>
   )
 }
+
+// The renderer a plugin registered for one tool through ui.tool, contained
+// like a slot contribution; the host's own row when none did.
+export function PluginTool(props: ParentProps<{ readonly input: SlotMap["session.part.tool"] }>) {
+  const plugins = usePlugin()
+  const claim = createMemo(() => plugins.tool(props.input.tool))
+  return (
+    // Keyed so a hot reload or a new owner recreates the boundary.
+    <Show keyed when={claim()} fallback={props.children}>
+      {(item) => (
+        <PluginBoundary id={item.plugin} where={`tool ${props.input.tool}`}>
+          {createComponent(item.render, mergeProps(() => props.input))}
+        </PluginBoundary>
+      )}
+    </Show>
+  )
+}
+
+// ui.Markdown: the transcript's markdown, with the current syntax style,
+// every registered code-block renderer and the user's markdown mode.
+export function PluginMarkdown(props: MarkdownProps) {
+  const plugins = usePlugin()
+  const theme = useTheme()
+  const { currentSyntax: syntax } = useThemes()
+  const config = useConfig()
+  return (
+    <markdown
+      syntaxStyle={syntax()}
+      renderNode={plugins.markdown()}
+      content={props.content}
+      streaming={props.streaming ?? false}
+      internalBlockMode="top-level"
+      tableOptions={{ style: "grid", cellPaddingX: 1 }}
+      conceal={(config.data.session?.markdown ?? "rendered") === "rendered"}
+      fg={props.fg ?? theme.markdown.text}
+      bg={props.bg ?? theme.background.base}
+    />
+  )
+}
diff --git a/packages/tui/src/routes/session/index.tsx b/packages/tui/src/routes/session/index.tsx
index f8be0b53308d..043be64e6ca6 100644
--- a/packages/tui/src/routes/session/index.tsx
+++ b/packages/tui/src/routes/session/index.tsx
@@ -100,7 +100,7 @@ import { collapseShellOutput, collapseToolOutput } from "../../util/collapse-too
 import { Keymap, type KeymapCommand } from "../../context/keymap"
 import { usePathFormatter } from "../../context/path-format"
 import { useLocation } from "../../context/location"
-import { Slot } from "../../plugin/render"
+import { PluginTool, Slot } from "../../plugin/render"
 import { usePlugin } from "../../plugin/context"
 import type { TranscriptRowKind } from "@opencode/plugin/tui/context"
 import {
@@ -242,11 +242,16 @@ export function Session(props: {
 
   const renderer = useRenderer()
   const dimensions = useTerminalDimensions()
-  const thinkingMode = createMemo<ThinkingMode>(() => config.session?.thinking ?? "hide")
+  // The user's choice wins over a plugin's transcript default.
+  const thinkingMode = createMemo<ThinkingMode>(
+    () => config.session?.thinking ?? plugins.layout().transcript?.thinking ?? "hide",
+  )
   const showScrollbar = createMemo(() => config.session?.scrollbar ?? false)
   const markdownMode = createMemo(() => config.session?.markdown ?? "rendered")
   const diffWrapMode = createMemo(() => config.diffs?.wrap ?? "word")
-  const groupExploration = createMemo(() => config.session?.grouping !== "none")
+  const groupExploration = createMemo(
+    () => (config.session?.grouping ?? plugins.layout().transcript?.grouping) !== "none",
+  )
   const verbosity = createMemo(() => config.session?.verbosity ?? defaultVerbosity)
   // High opens exploration and instruction summaries by default; everything else starts collapsed.
   const groupExpanded = (groupID: string, kind: GroupKind) =>
@@ -2027,6 +2032,10 @@ function SessionPartView(props: {
   })
   const ctx = use()
   const input = () => ({ sessionID: ctx.sessionID, messageID: props.partRef.messageID, partID: props.partRef.partID })
+  const toolInput = () => {
+    const item = part()
+    return { ...input(), tool: item?.type === "tool" ? canonicalToolName(item.name) : "" }
+  }
   return (
     <Show when={part()}>
       {(item) => (
@@ -2050,11 +2059,10 @@ function SessionPartView(props: {
             </Slot>
           </Match>
           <Match when={item().type === "tool"}>
-            <Slot
-              path="session.part.tool"
-              input={{ ...input(), tool: canonicalToolName((item() as SessionMessageAssistantTool).name) }}
-            >
-              <ToolPart part={item() as SessionMessageAssistantTool} images={props.images} />
+            <Slot path="session.part.tool" input={toolInput()}>
+              <PluginTool input={toolInput()}>
+                <ToolPart part={item() as SessionMessageAssistantTool} images={props.images} />
+              </PluginTool>
             </Slot>
           </Match>
         </Switch>

From b74c4ac4b8826ce8ea800140d8b3405857533dd2 Mon Sep 17 00:00:00 2001
From: cevr <seeve.c@gmail.com>
Date: Tue, 3 Nov 2026 23:13:45 -0500
Subject: [PATCH 4/6] test(tui): cover the session read and transcript plugin
 hooks

---
 .../test/fixture/plugin/session-reads/tui.tsx |  42 ++++
 .../test/fixture/plugin/tool-renderer/tui.tsx |  23 +++
 .../fixture/plugin/transcript-chrome/tui.tsx  |  30 +++
 .../tui/test/plugin-session-hooks.test.tsx    | 186 ++++++++++++++++++
 4 files changed, 281 insertions(+)
 create mode 100644 packages/tui/test/fixture/plugin/session-reads/tui.tsx
 create mode 100644 packages/tui/test/fixture/plugin/tool-renderer/tui.tsx
 create mode 100644 packages/tui/test/fixture/plugin/transcript-chrome/tui.tsx
 create mode 100644 packages/tui/test/plugin-session-hooks.test.tsx

diff --git a/packages/tui/test/fixture/plugin/session-reads/tui.tsx b/packages/tui/test/fixture/plugin/session-reads/tui.tsx
new file mode 100644
index 000000000000..9afc3eb6426b
--- /dev/null
+++ b/packages/tui/test/fixture/plugin/session-reads/tui.tsx
@@ -0,0 +1,42 @@
+import { Plugin } from "@opencode/plugin/tui"
+import { TextRenderable } from "@opentui/core"
+
+// Reads a session through data.session.usage, data.session.goal and
+// data.session.part.get, and renders a text part with ui.Markdown.
+export default Plugin.define({
+  id: "fixture.session-reads",
+  setup(context) {
+    context.markdown.registerCodeBlockRenderer(
+      "probe",
+      () => new TextRenderable(context.renderer, { content: "Probe fence rendered", height: 1 }),
+    )
+    context.ui.slot({
+      append: "session.header",
+      render: (input) => {
+        const usage = () => context.data.session.usage(input.sessionID)
+        const goal = () => context.data.session.goal(input.sessionID)
+        return (
+          <box flexDirection="column">
+            <text>
+              usage {usage()?.tokens ?? "none"} of {usage()?.limit ?? "none"} ({usage()?.percent ?? "none"}%)
+            </text>
+            <text>
+              goal {goal()?.objective ?? "none"} [{goal()?.status ?? "none"}]
+            </text>
+          </box>
+        )
+      },
+    })
+    context.ui.slot({
+      replace: "session.part.text",
+      render: (input) => {
+        const part = () => context.data.session.part.get(input.sessionID, input.messageID, input.partID)
+        const content = () => {
+          const item = part()
+          return item?.type === "text" ? `Read ${input.partID}: ${item.text}` : ""
+        }
+        return <context.ui.Markdown content={content()} />
+      },
+    })
+  },
+})
diff --git a/packages/tui/test/fixture/plugin/tool-renderer/tui.tsx b/packages/tui/test/fixture/plugin/tool-renderer/tui.tsx
new file mode 100644
index 000000000000..0efedcf150c0
--- /dev/null
+++ b/packages/tui/test/fixture/plugin/tool-renderer/tui.tsx
@@ -0,0 +1,23 @@
+import { Plugin } from "@opencode/plugin/tui"
+
+// Renders every shell call itself and asks for an ungrouped transcript with
+// reasoning shown.
+export default Plugin.define({
+  id: "fixture.tool-renderer",
+  setup(context) {
+    context.ui.layout({ transcript: { grouping: "none", thinking: "show" } })
+    context.ui.tool("shell", (input) => {
+      const part = () => context.data.session.part.get(input.sessionID, input.messageID, input.partID)
+      const command = () => {
+        const item = part()
+        if (item?.type !== "tool" || typeof item.state.input === "string") return ""
+        return String((item.state.input as { command?: unknown }).command ?? "")
+      }
+      return (
+        <text>
+          Custom {input.tool} row: {command()}
+        </text>
+      )
+    })
+  },
+})
diff --git a/packages/tui/test/fixture/plugin/transcript-chrome/tui.tsx b/packages/tui/test/fixture/plugin/transcript-chrome/tui.tsx
new file mode 100644
index 000000000000..64c7d411dc25
--- /dev/null
+++ b/packages/tui/test/fixture/plugin/transcript-chrome/tui.tsx
@@ -0,0 +1,30 @@
+import { Plugin } from "@opencode/plugin/tui"
+
+// Claims the transcript's chrome: a header, a first row, the user prompt and
+// the turn footer, with tight rows, a one-cell inset and a band composer.
+export default Plugin.define({
+  id: "fixture.transcript-chrome",
+  setup(context) {
+    context.ui.layout({
+      inset: 1,
+      rowGap: (row) => (row.kind === "footer" ? 0 : 1),
+      composer: { chrome: "band", prefix: "> " },
+    })
+    context.ui.slot({ append: "session.header", render: () => <text>Header claimed</text> })
+    context.ui.slot({ append: "session.transcript.start", render: () => <text>Transcript start claimed</text> })
+    context.ui.slot({
+      replace: "session.message.user",
+      render: (input) => {
+        const text = () => {
+          const message = context.data.session.message.get(input.sessionID, input.messageID)
+          return message?.type === "user" ? message.text : ""
+        }
+        return <text>User band: {text()}</text>
+      },
+    })
+    context.ui.slot({
+      replace: "session.message.assistant.footer",
+      render: (input) => <text>Footer for {input.messageID}</text>,
+    })
+  },
+})
diff --git a/packages/tui/test/plugin-session-hooks.test.tsx b/packages/tui/test/plugin-session-hooks.test.tsx
new file mode 100644
index 000000000000..67d0b934793d
--- /dev/null
+++ b/packages/tui/test/plugin-session-hooks.test.tsx
@@ -0,0 +1,186 @@
+import { expect, test } from "bun:test"
+import { createAppFixture } from "./fixture/app"
+import { copyPlugin } from "./fixture/fixture"
+import { waitForHighlightedFrame } from "./fixture/frame"
+import { directory, json } from "./fixture/tui-client"
+
+const session = {
+  id: "ses_plugin_hooks",
+  title: "Plugin hooks",
+  projectID: "proj_test",
+  location: { directory },
+  cost: 0,
+  tokens: { input: 0, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
+  time: { created: 0, updated: 0 },
+}
+const model = { providerID: "fixture", id: "fixture" }
+// Newest first, as the server pages them.
+const messages = [
+  {
+    type: "assistant",
+    id: "msg_reply",
+    agent: "build",
+    model,
+    finish: "stop",
+    time: { created: 2, completed: 3 },
+    // 2,000 tokens of a 8,000-token window.
+    tokens: { input: 1000, output: 200, reasoning: 0, cache: { read: 800, write: 0 } },
+    content: [
+      { type: "reasoning", text: "Weighing the parser fix", time: { created: 2, completed: 2 } },
+      {
+        type: "tool",
+        id: "call_shell",
+        name: "bash",
+        time: { created: 2, completed: 3 },
+        state: {
+          status: "completed",
+          input: { command: "bun test parser" },
+          content: [{ type: "text", text: "1 pass" }],
+          metadata: {},
+        },
+      },
+      { type: "text", text: "The **parser** is fixed.\n\n```probe\nanything\n```" },
+    ],
+  },
+  { type: "user", id: "msg_ask", text: "Fix the parser", time: { created: 1 } },
+]
+const goal = {
+  id: "goal",
+  objective: "Ship the parser",
+  status: "active",
+  rounds: 1,
+  maxRounds: 50,
+  boot: "boot",
+  updatedAt: 0,
+}
+
+async function openSession(plugin: string) {
+  const fixture = await copyPlugin(plugin)
+  const setup = await createAppFixture({
+    width: 100,
+    height: 30,
+    config: { animations: false, tabs: { enabled: false }, plugins: [fixture.directory] },
+    args: { sessionID: session.id },
+    fetch: (url) => {
+      if (url.pathname === "/api/session") return json({ data: [session], cursor: {} })
+      if (url.pathname === `/api/session/${session.id}`) return json({ data: session })
+      if (url.pathname === `/api/session/${session.id}/message`) return json({ data: messages, cursor: {} })
+      if (/^\/api\/session\/[^/]+\/(inbox|permission)$/.test(url.pathname)) return json({ data: [] })
+      if (url.pathname === "/api/model")
+        return json({
+          location: { directory, project: { id: "proj_test", directory, canonical: directory } },
+          data: [{ ...model, name: "Fixture", variants: [], limit: { context: 8000, output: 1000 } }],
+        })
+      if (url.pathname === "/api/rpc/opencode.goal/get") return json({ output: goal })
+      return undefined
+    },
+  })
+  const dispose = setup[Symbol.asyncDispose]
+  return Object.assign(setup, {
+    async [Symbol.asyncDispose]() {
+      await dispose()
+      await fixture[Symbol.asyncDispose]()
+    },
+  })
+}
+
+test("a plugin reads a session's context usage, goal and parts, and renders host markdown", async () => {
+  await using app = await openSession("session-reads")
+  await app.ready
+  // part.get resolves text parts by ordinal; ui.Markdown conceals the markup and runs registered fence renderers.
+  const frame = await waitForHighlightedFrame(
+    app,
+    (frame) =>
+      frame.includes("usage 2000 of 8000 (25%)") &&
+      frame.includes("goal Ship the parser [active]") &&
+      frame.includes("Read text:0: The parser is fixed.") &&
+      frame.includes("Probe fence rendered"),
+  )
+  expect(frame).not.toContain("**parser**")
+  expect(frame).not.toContain("```")
+
+  // The goal follows the goal plugin's changes.
+  app.events.emit({
+    id: "evt_goal_changed",
+    created: 4,
+    type: "rpc.opencode.goal.changed",
+    location: { directory },
+    data: { sessionID: session.id, goal: { ...goal, status: "paused" } },
+  })
+  await app.waitForFrame((frame) => frame.includes("goal Ship the parser [paused]"))
+  app.events.emit({
+    id: "evt_goal_cleared",
+    created: 5,
+    type: "rpc.opencode.goal.changed",
+    location: { directory },
+    data: { sessionID: session.id, goal: null },
+  })
+  await app.waitForFrame((frame) => frame.includes("goal none [none]"))
+})
+
+test("a plugin renders one tool by canonical name and sets transcript defaults", async () => {
+  await using app = await openSession("tool-renderer")
+  await app.ready
+  // `bash` is the shell tool's canonical name; grouping "none" keeps the call its own row.
+  // thinking "show" expands reasoning the host hides by default.
+  await waitForHighlightedFrame(
+    app,
+    (frame) =>
+      frame.includes("Custom shell row: bun test parser") &&
+      frame.includes("Weighing the parser fix") &&
+      frame.includes("The parser is fixed."),
+  )
+})
+
+test("the user's transcript config wins over a plugin's defaults", async () => {
+  const fixture = await copyPlugin("tool-renderer")
+  try {
+    await using app = await createAppFixture({
+      width: 100,
+      height: 30,
+      config: {
+        animations: false,
+        tabs: { enabled: false },
+        plugins: [fixture.directory],
+        session: { thinking: "hide" },
+      },
+      args: { sessionID: session.id },
+      fetch: (url) => {
+        if (url.pathname === "/api/session") return json({ data: [session], cursor: {} })
+        if (url.pathname === `/api/session/${session.id}`) return json({ data: session })
+        if (url.pathname === `/api/session/${session.id}/message`) return json({ data: messages, cursor: {} })
+        if (/^\/api\/session\/[^/]+\/(inbox|permission)$/.test(url.pathname)) return json({ data: [] })
+        return undefined
+      },
+    })
+    await app.ready
+    const frame = await app.waitForFrame((frame) => frame.includes("Custom shell row: bun test parser"))
+    expect(frame).not.toContain("Weighing the parser fix")
+  } finally {
+    await fixture[Symbol.asyncDispose]()
+  }
+})
+
+test("a plugin claims the transcript's header, first row, user prompt and turn footer", async () => {
+  await using app = await openSession("transcript-chrome")
+  await app.ready
+  const frame = await waitForHighlightedFrame(
+    app,
+    (frame) =>
+      frame.includes("Header claimed") &&
+      frame.includes("Transcript start claimed") &&
+      frame.includes("User band: Fix the parser") &&
+      frame.includes("The parser is fixed.") &&
+      frame.includes("Footer for msg_reply"),
+  )
+  const lines = frame.split("\n")
+  // inset 1 starts rows one cell in.
+  expect(lines.find((line) => line.includes("User band"))).toStartWith(" User band")
+  // rowGap 0 for the footer puts it straight under the reply; every other row keeps one blank row above it.
+  const footer = lines.findIndex((line) => line.includes("Footer for msg_reply"))
+  expect(lines[footer - 1]).toContain("anything")
+  const user = lines.findIndex((line) => line.includes("User band"))
+  expect(lines[user - 1]?.trim()).toBe("")
+  // The band composer puts its prefix before the editor. Its bar is still drawn, in the band's colour.
+  expect(lines.some((line) => line.startsWith(" ┃> "))).toBe(true)
+})

From 1ccbce16ed427266986c4ad3f17a484a6528eda3 Mon Sep 17 00:00:00 2001
From: cevr <seeve.c@gmail.com>
Date: Wed, 4 Nov 2026 10:37:53 -0500
Subject: [PATCH 5/6] fix(tui): paint the band composer's background and
 prefix; drop the unused opt-in set

---
 packages/tui/src/component/prompt/index.tsx | 184 ++++++++++----------
 packages/tui/src/plugin/builtins.ts         |   4 -
 packages/tui/src/plugin/context.tsx         |   4 +-
 3 files changed, 96 insertions(+), 96 deletions(-)

diff --git a/packages/tui/src/component/prompt/index.tsx b/packages/tui/src/component/prompt/index.tsx
index a4d54ba1eccd..261520e5567b 100644
--- a/packages/tui/src/component/prompt/index.tsx
+++ b/packages/tui/src/component/prompt/index.tsx
@@ -1692,15 +1692,19 @@ export function Prompt(props: PromptProps) {
       <box ref={(r: BoxRenderable) => (anchor = r)} visible={props.visible !== false} width="100%">
         <box
           width="100%"
-          border={band() ? undefined : ["left"]}
-          borderColor={borderHighlight()}
+          border={["left"]}
+          // Workaround: an OpenTUI box keeps its border once styled (setting
+          // `border` back to false leaves the bar drawn), so the band paints the
+          // bar in the band colour instead of removing it.
+          borderColor={band() ? promptBg() : borderHighlight()}
+          backgroundColor={band() ? promptBg() : undefined}
           customBorderChars={{
             ...SplitBorder.customBorderChars,
             bottomLeft: "╹",
           }}
         >
           <box
-            paddingLeft={band() ? 1 : dimensions().width < 44 ? 1 : 2}
+            paddingLeft={band() ? 0 : dimensions().width < 44 ? 1 : 2}
             paddingRight={dimensions().width < 44 ? 1 : 2}
             paddingTop={1}
             paddingBottom={band() ? 1 : 0}
@@ -1778,95 +1782,95 @@ export function Prompt(props: PromptProps) {
               </box>
             </Show>
             <box flexDirection="row" width="100%">
-            <Show when={band()?.prefix}>{(prefix) => <text fg={theme.text.base}>{prefix()}</text>}</Show>
-            <textarea
-              flexGrow={1}
-              flexShrink={1}
-              placeholder={placeholderText()}
-              placeholderColor={theme.text.muted}
-              textColor={muted() ? theme.text.muted : theme.text.base}
-              focusedTextColor={muted() ? theme.text.muted : theme.text.base}
-              minHeight={1}
-              maxHeight={maxHeight()}
-              cursorStyle={cursorStyle()}
-              onContentChange={() => {
-                const value = input.plainText
-                setStore("prompt", "text", value)
-                auto()?.onInput(value)
-                syncExtmarksWithPromptParts()
-                setCursorVersion((value) => value + 1)
-              }}
-              onCursorChange={() => setCursorVersion((value) => value + 1)}
-              onKeyDown={(e: { preventDefault(): void }) => {
-                if (disabled()) {
-                  e.preventDefault()
-                  return
-                }
-              }}
-              onSubmit={() => {
-                if (disabled()) return
-                // IME: double-defer so the last composed character (e.g. Korean
-                // hangul) is flushed to plainText before we read it for submission.
-                setTimeout(() => setTimeout(() => submit(), 0), 0)
-              }}
-              onPaste={(event: PasteEvent) => {
-                if (disabled()) {
+              <Show when={band()?.prefix}>{(prefix) => <text fg={theme.text.base}>{prefix()}</text>}</Show>
+              <textarea
+                flexGrow={1}
+                flexShrink={1}
+                placeholder={placeholderText()}
+                placeholderColor={theme.text.muted}
+                textColor={muted() ? theme.text.muted : theme.text.base}
+                focusedTextColor={muted() ? theme.text.muted : theme.text.base}
+                minHeight={1}
+                maxHeight={maxHeight()}
+                cursorStyle={cursorStyle()}
+                onContentChange={() => {
+                  const value = input.plainText
+                  setStore("prompt", "text", value)
+                  auto()?.onInput(value)
+                  syncExtmarksWithPromptParts()
+                  setCursorVersion((value) => value + 1)
+                }}
+                onCursorChange={() => setCursorVersion((value) => value + 1)}
+                onKeyDown={(e: { preventDefault(): void }) => {
+                  if (disabled()) {
+                    e.preventDefault()
+                    return
+                  }
+                }}
+                onSubmit={() => {
+                  if (disabled()) return
+                  // IME: double-defer so the last composed character (e.g. Korean
+                  // hangul) is flushed to plainText before we read it for submission.
+                  setTimeout(() => setTimeout(() => submit(), 0), 0)
+                }}
+                onPaste={(event: PasteEvent) => {
+                  if (disabled()) {
+                    event.preventDefault()
+                    return
+                  }
+
+                  // Normalize line endings at the boundary
+                  // Windows ConPTY/Terminal often sends CR-only newlines in bracketed paste
+                  // Replace CRLF first, then any remaining CR
+                  const normalizedText = decodePasteBytes(event.bytes).replace(/\r\n/g, "\n").replace(/\r/g, "\n")
+
+                  // Windows Terminal <1.25 can surface image-only clipboard as an
+                  // empty bracketed paste. Windows Terminal 1.25+ does not.
+                  if (event.bytes.byteLength === 0) {
+                    keymap.dispatch("prompt.paste")
+                    return
+                  }
+
+                  // Once we cross an async boundary below, the terminal may perform its
+                  // default paste unless we suppress it first and handle insertion ourselves.
                   event.preventDefault()
-                  return
-                }
-
-                // Normalize line endings at the boundary
-                // Windows ConPTY/Terminal often sends CR-only newlines in bracketed paste
-                // Replace CRLF first, then any remaining CR
-                const normalizedText = decodePasteBytes(event.bytes).replace(/\r\n/g, "\n").replace(/\r/g, "\n")
-
-                // Windows Terminal <1.25 can surface image-only clipboard as an
-                // empty bracketed paste. Windows Terminal 1.25+ does not.
-                if (event.bytes.byteLength === 0) {
-                  keymap.dispatch("prompt.paste")
-                  return
-                }
-
-                // Once we cross an async boundary below, the terminal may perform its
-                // default paste unless we suppress it first and handle insertion ourselves.
-                event.preventDefault()
-
-                void enqueuePaste((changed) => pasteInputText(normalizedText, changed))
-              }}
-              ref={(r: TextareaRenderable) => {
-                input = r
-                Object.assign(r, {
-                  getClipboardText: (text: string) => expandPastedTextPlaceholders(text, store.prompt.pasted),
-                })
-                setInputTarget(r)
-                if (promptPartTypeId === 0) {
-                  promptPartTypeId = input.extmarks.registerType("prompt-part")
-                }
-                props.ref?.(ref)
-                setTimeout(() => {
-                  // setTimeout is a workaround and needs to be addressed properly
-                  if (!input || input.isDestroyed) return
-                  input.cursorColor = disabled() ? theme.background.raised.base : theme.text.base
-                }, 0)
-              }}
-              onMouseDown={(r: MouseEvent) => {
-                if (disabled()) {
+
+                  void enqueuePaste((changed) => pasteInputText(normalizedText, changed))
+                }}
+                ref={(r: TextareaRenderable) => {
+                  input = r
+                  Object.assign(r, {
+                    getClipboardText: (text: string) => expandPastedTextPlaceholders(text, store.prompt.pasted),
+                  })
+                  setInputTarget(r)
+                  if (promptPartTypeId === 0) {
+                    promptPartTypeId = input.extmarks.registerType("prompt-part")
+                  }
+                  props.ref?.(ref)
+                  setTimeout(() => {
+                    // setTimeout is a workaround and needs to be addressed properly
+                    if (!input || input.isDestroyed) return
+                    input.cursorColor = disabled() ? theme.background.raised.base : theme.text.base
+                  }, 0)
+                }}
+                onMouseDown={(r: MouseEvent) => {
+                  if (disabled()) {
+                    r.preventDefault()
+                    return
+                  }
+                  if (r.button !== 0) return
+                  r.target?.focus()
+                  const extmark = input.extmarks
+                    .getAtOffset(input.cursorOffset)
+                    .find((item) => store.extmarkToPart.get(item.id)?.type === "pasted")
+                  if (!extmark || !expandPastedText(extmark.id)) return
                   r.preventDefault()
-                  return
-                }
-                if (r.button !== 0) return
-                r.target?.focus()
-                const extmark = input.extmarks
-                  .getAtOffset(input.cursorOffset)
-                  .find((item) => store.extmarkToPart.get(item.id)?.type === "pasted")
-                if (!extmark || !expandPastedText(extmark.id)) return
-                r.preventDefault()
-                r.stopPropagation()
-              }}
-              focusedBackgroundColor="transparent"
-              cursorColor={disabled() ? theme.background.raised.base : theme.text.base}
-              syntaxStyle={syntax()}
-            />
+                  r.stopPropagation()
+                }}
+                focusedBackgroundColor="transparent"
+                cursorColor={disabled() ? theme.background.raised.base : theme.text.base}
+                syntaxStyle={syntax()}
+              />
             </box>
             <box
               flexDirection="row"
diff --git a/packages/tui/src/plugin/builtins.ts b/packages/tui/src/plugin/builtins.ts
index a505ac850a6a..3f6a5728efda 100644
--- a/packages/tui/src/plugin/builtins.ts
+++ b/packages/tui/src/plugin/builtins.ts
@@ -14,10 +14,6 @@ import Stats from "../feature-plugins/system/stats"
 import Latex from "@opencode/latex/plugin"
 import Merman from "@opencode/merman/plugin"
 
-// Builtins listed here start disabled; a tui config `plugins` entry naming
-// the id enables them.
-export const optIn: ReadonlySet<string> = new Set<string>()
-
 export const builtins = [
   HomeFooter,
   PromptFooter,
diff --git a/packages/tui/src/plugin/context.tsx b/packages/tui/src/plugin/context.tsx
index 6103de240164..c7a2759da7a8 100644
--- a/packages/tui/src/plugin/context.tsx
+++ b/packages/tui/src/plugin/context.tsx
@@ -347,10 +347,10 @@ export function PluginProvider(props: ParentProps<{ packages: PackageSource; dir
 
     // Resolve: fold entries into one desired generation. A source that fails
     // to import keeps its running previous version and only reports failure.
-    const { builtins, optIn } = await import("./builtins")
+    const { builtins } = await import("./builtins")
     const desired = new Map<string, Desired>()
     for (const plugin of builtins)
-      desired.set(plugin.id, { plugin, source: "builtin", version: "builtin", enabled: !optIn.has(plugin.id) })
+      desired.set(plugin.id, { plugin, source: "builtin", version: "builtin", enabled: true })
     const failures: State[] = []
     for (const source of entries) {
       const entry = source.entry

From f604c8dc7980e5424a36717ec6d0de39c4361501 Mon Sep 17 00:00:00 2001
From: cevr <seeve.c@gmail.com>
Date: Wed, 4 Nov 2026 11:00:41 -0500
Subject: [PATCH 6/6] fix(tui): keep the transcript hooks clear of history
 anchoring and header shrink

The transcript-start slot stays above the rows while older history loads
beneath it, so the scroll anchor skips it. The header slot keeps its height
instead of shrinking under the transcript.
---
 packages/tui/src/context/data.tsx              | 10 +++++-----
 .../tui/src/feature-plugins/prompt/goal.tsx    |  6 +-----
 packages/tui/src/plugin/render.tsx             |  5 ++++-
 packages/tui/src/routes/session/index.tsx      | 18 +++++++++++++++---
 4 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/packages/tui/src/context/data.tsx b/packages/tui/src/context/data.tsx
index 5942f67ed412..54aea7e1715d 100644
--- a/packages/tui/src/context/data.tsx
+++ b/packages/tui/src/context/data.tsx
@@ -104,11 +104,11 @@ function createGoals(input: {
     const current = turn(sessionID)
     // A server without the goal plugin answers with an error, and the session shows no goal.
     void input.fetch(sessionID).then(
-        (goal) => {
-          if (turns.get(sessionID) === current) set(sessionID, goal)
-        },
-        () => undefined,
-      )
+      (goal) => {
+        if (turns.get(sessionID) === current) set(sessionID, goal)
+      },
+      () => undefined,
+    )
   }
   onCleanup(
     input.on(`rpc.${Goal.Definition.id}.changed`, (event) => {
diff --git a/packages/tui/src/feature-plugins/prompt/goal.tsx b/packages/tui/src/feature-plugins/prompt/goal.tsx
index 52b2604f0f19..ee42d440eee6 100644
--- a/packages/tui/src/feature-plugins/prompt/goal.tsx
+++ b/packages/tui/src/feature-plugins/prompt/goal.tsx
@@ -65,11 +65,7 @@ function showGoal(context: Plugin.Context, sessionID: string, goal: Accessor<Ses
   context.ui.dialog.show(() => <GoalDialog context={context} sessionID={sessionID} goal={goal} />)
 }
 
-function GoalDialog(props: {
-  context: Plugin.Context
-  sessionID: string
-  goal: Accessor<SessionGoal | undefined>
-}) {
+function GoalDialog(props: { context: Plugin.Context; sessionID: string; goal: Accessor<SessionGoal | undefined> }) {
   const theme = useTheme().surface("dialog")
   const goal = props.goal
   const run = (text: "pause" | "resume" | "clear") => {
diff --git a/packages/tui/src/plugin/render.tsx b/packages/tui/src/plugin/render.tsx
index 6ef11f84ae65..76c8fb4ed239 100644
--- a/packages/tui/src/plugin/render.tsx
+++ b/packages/tui/src/plugin/render.tsx
@@ -169,7 +169,10 @@ export function PluginTool(props: ParentProps<{ readonly input: SlotMap["session
     <Show keyed when={claim()} fallback={props.children}>
       {(item) => (
         <PluginBoundary id={item.plugin} where={`tool ${props.input.tool}`}>
-          {createComponent(item.render, mergeProps(() => props.input))}
+          {createComponent(
+            item.render,
+            mergeProps(() => props.input),
+          )}
         </PluginBoundary>
       )}
     </Show>
diff --git a/packages/tui/src/routes/session/index.tsx b/packages/tui/src/routes/session/index.tsx
index 043be64e6ca6..b31c6e4e9f6f 100644
--- a/packages/tui/src/routes/session/index.tsx
+++ b/packages/tui/src/routes/session/index.tsx
@@ -148,6 +148,9 @@ const BACKGROUND_TOOL_HINT_DELAY = 3_000
 const TRANSCRIPT_TAIL_ROWS = 40
 const TRANSCRIPT_BACKFILL_CHUNK = 60
 
+/** The box holding the session.transcript.start slot, first in the transcript scroll. */
+const TRANSCRIPT_START = "session-transcript-start"
+
 export function Session(props: {
   scrollRef?: (scroll: ScrollBoxRenderable | undefined) => void
   verticalTabsWidth: number
@@ -420,7 +423,10 @@ export function Session(props: {
   const pinAbove = () => {
     if (!scroll || scroll.isDestroyed) return
     if (scroll.stickyScroll && scroll.scrollTop >= scroll.scrollHeight - scroll.viewport.height) return
-    const node = scroll.getChildren().find((node) => node.height > 0 && node.y + node.height > scroll.viewport.y)
+    // The transcript-start slot stays on top while older rows load beneath it, so it never anchors.
+    const node = scroll
+      .getChildren()
+      .find((node) => node.id !== TRANSCRIPT_START && node.height > 0 && node.y + node.height > scroll.viewport.y)
     if (node) afterLayout(scroll.anchor(node))
   }
 
@@ -1529,7 +1535,10 @@ export function Session(props: {
           paddingRight={plugins.layout().inset ?? (dimensions().width < 44 ? 1 : 2)}
         >
           <Show when={session()}>
-            <Slot path="session.header" input={{ sessionID: route.sessionID }} />
+            {/* Keeps its full height; the transcript below takes what is left. */}
+            <box flexShrink={0}>
+              <Slot path="session.header" input={{ sessionID: route.sessionID }} />
+            </box>
             <box flexGrow={1} minHeight={0} position="relative">
               <scrollbox
                 ref={(r) => {
@@ -1559,7 +1568,10 @@ export function Session(props: {
                   updateAwayFromBottom()
                 }}
               >
-                <Slot path="session.transcript.start" input={{ sessionID: route.sessionID }} />
+                {/* Pinned above every row, so the history scroll anchor skips it (pinAbove). */}
+                <box id={TRANSCRIPT_START} flexShrink={0}>
+                  <Slot path="session.transcript.start" input={{ sessionID: route.sessionID }} />
+                </box>
                 <For each={visibleRows()}>
                   {(row, index) => (
                     <SessionRowView