feat(web): a prose mention of a produced file opens it

The chatFileMentions service (provided by ui-deliverables beside its
turn-tail entry, reached via ctx.get) resolves inline-code tokens in the
closing message against the turn's produced locations: exact path or
unique basename links, ambiguity and unknowns stay inert. MarkdownText
gains the optional fileMentions seam — settled renders only, never
inside anchors.

packages/client/ui-conversation/src/client/apply.ts

@@ -313,6 +313,7 @@ export function apply(ctx: Context): void {
           actions.select(target)
           layout.openDetails()
         },
+        fileMentions: owner => ctx.get('chatFileMentions')?.forClosing(owner),
         openFile: (path) => {
           const cwd = sessions.list.getSnapshot().byId[sessionId]?.cwd
           void workspaces.openPath(resolveToolPath(cwd, path)).catch(() => {

packages/client/ui-conversation/src/client/chat/AssistantMarkdown.tsx

@@ -15,7 +15,8 @@ import type { PropsRenderSlots } from '@deepseek-ai/dsh-client-ui-slots'
 import {
   IconThinkOutline14, JsonBlock, MarkdownText,
 } from '@deepseek-ai/dsh-client-ui-primitives'
-import type { ChatViewSlotProps, TurnTailOwnerProps } from '../contract/slots.ts'
+import type { MarkdownFileMentions } from '@deepseek-ai/dsh-client-ui-primitives'
+import type { ChatViewSlotProps, ChatViewInjected, TurnTailOwnerProps } from '../contract/slots.ts'
 import { hasContentText } from './chat-flow.ts'
 import { MessageIconActions } from './MessageIconActions.tsx'
 import { ToolRow } from './ToolRow.tsx'
@@ -43,6 +44,8 @@ export interface AssistantMarkdownProps {
   onFork?: ((seq: number) => void) | undefined
   /** Turn-tail slot dispatch share and owner currency; omitted for a mid-turn assistant. */
   turnTail?: (Pick<PropsRenderSlots<'conversation.chat.turnTail'>, 'renderSlotChain'> & { owner: TurnTailOwnerProps }) | undefined
+  /** Prose file-mention factory (the injected face); omitted wherever `turnTail` is. */
+  fileMentions?: ChatViewInjected['fileMentions'] | undefined
   /** The message is not the transcript tail of a completed turn. */
   forkUnavailable?: boolean | undefined
   /** The owning view's locale seat, passed down as a plain prop. */
@@ -86,11 +89,25 @@ function ThinkRow({ text, running, t }: { text: string; running: boolean; t: Ass
 }
 
 export const AssistantMarkdown = memo(function AssistantMarkdown({
-  blocks, streaming, interrupted, time, runMs, ttftMs, tokensPerSecond, seq, onFork, forkUnavailable, turnTail, t,
+  blocks, streaming, interrupted, time, runMs, ttftMs, tokensPerSecond, seq, onFork, forkUnavailable, turnTail,
+  fileMentions, t,
 }: AssistantMarkdownProps) {
   // Stable per locale revision (t identity changes on switch): a fresh object
   // per render would rebuild MarkdownText's component table every chunk.
   const codeLabels = useMemo(() => ({ copyLabel: t('copy'), copiedLabel: t('copied') }), [t])
+  // Mention vocabulary for the closing prose. Keyed on the anchor seq, not the
+  // growing transcript: a settled turn's produced files are final, and a
+  // fresh identity per append would discard MarkdownText's cached parse for
+  // every settled closing message on every stream chunk. The window-prepend
+  // edge (a mid-turn window start later gaining earlier same-turn writes)
+  // leaves a mention unlinked until remount — never a wrong link.
+  const owner = turnTail?.owner
+  const mentions: MarkdownFileMentions | undefined = useMemo(
+    () => (owner === undefined ? undefined : fileMentions?.(owner)),
+    // Deliberately not `owner`: its identity changes per append while the
+    // seq-addressed vocabulary it yields does not.
+    [fileMentions, owner?.seq],
+  )
   const last = blocks.length - 1
   // Tool-call heads render as tool rows in the chat view's grouping pass, so
   // a node that is only those heads (or empty) would paint an empty root
@@ -107,7 +124,13 @@ export const AssistantMarkdown = memo(function AssistantMarkdown({
         {blocks.map((block, i) => {
           switch (block.kind) {
             case 'text': return (
-              <MarkdownText key={i} text={block.text} streaming={streaming} codeLabels={codeLabels} />
+              <MarkdownText
+                key={i}
+                text={block.text}
+                streaming={streaming}
+                codeLabels={codeLabels}
+                fileMentions={mentions}
+              />
             )
             case 'reasoning': return <ThinkRow key={i} text={block.text} running={streaming && i === last} t={t} />
             // Grouped into tool rows by ChatView; hasVisible above skips an empty shell.

packages/client/ui-conversation/src/client/chat/ChatView.tsx

@@ -335,7 +335,8 @@ function StreamingTail({ useSession, t }: {
  * render through the declared keyed hole's renderSlot share).
  */
 export function ChatView({
-  useSession, useSessions, useStore, renderSlot, renderSlotChain, sessionId, openFile, loadOlder, inspectCall, chatScroll, forkAt, t,
+  useSession, useSessions, useStore, renderSlot, renderSlotChain, sessionId, openFile, loadOlder, inspectCall, chatScroll, forkAt,
+  fileMentions, t,
 }: ChatViewSlotProps) {
   const nodes = useSession(s => s.nodes)
   const turnTimings = useSession(s => s.turnTimings)
@@ -603,6 +604,7 @@ export function ChatView({
           turnTail={actionSeqs.has(node.seq)
             ? { renderSlotChain, owner: { nodes, seq: node.seq, openFile } }
             : undefined}
+          fileMentions={actionSeqs.has(node.seq) ? fileMentions : undefined}
           t={t}
         />
       )

packages/client/ui-conversation/src/client/contract/slots.ts

@@ -4,6 +4,7 @@ import type {
   InjectFace, MaybeSnapshotSelectorHook, PropsLocale, PropsRenderSlots, PropsRuntime, PropsStore, SnapshotSelectorHook,
 } from '@deepseek-ai/dsh-client-ui-slots'
 import type { CommandNode, ConversationNode, ConversationSnapshot, ObservableSnapshot, PendingInteraction, PendingWait, SessionId, ToolCallBlock, WorkspaceId } from '@deepseek-ai/dsh-client-runtime/client'
+import type { MarkdownFileMentions } from '@deepseek-ai/dsh-client-ui-primitives'
 import type {} from '@deepseek-ai/dsh-client-ui-layout/client'
 import type { ComposerKeyboard, EditSelection, InputActions, InputNotice, InputState } from '../input/contract.ts'
 import type { createChatStore } from '../stores.ts'
@@ -158,6 +159,30 @@ export interface ConvViewOwnerProps {
   onInspectDone?: () => void
 }
 
+/**
+ * Optional prose file-mention provider, consumed via `ctx.get('chatFileMentions')`
+ * (optional-service convention): the chat view asks it for a closing message's
+ * inline-code vocabulary and threads the result into MarkdownText. Absent
+ * service — the providing plugin composed out of cordis.yml — turns the
+ * surface off; the prose renders inert code.
+ */
+export interface ChatFileMentions {
+  /**
+   * Mention vocabulary for the closing message the owner currency names.
+   * @param owner - Turn-tail owner currency (nodes, closing seq, opener).
+   * @returns The resolver MarkdownText consumes, or undefined when the turn
+   * produced nothing worth linking.
+   */
+  forClosing(owner: TurnTailOwnerProps): MarkdownFileMentions | undefined
+}
+
+declare module 'cordis' {
+  interface Context {
+    /** Prose file-mention provider (ui-deliverables); reach via ctx.get — optional. */
+    chatFileMentions: ChatFileMentions
+  }
+}
+
 /**
  * Owner currency of the chat view's turn-tail hole: the finalized snapshot
  * and the closing assistant's anchor. Registrants derive their own facts
@@ -502,6 +527,13 @@ export interface ChatViewInjected {
   }
   /** Fork through the completed turn ending at the eligible message `seq`, then open the child. */
   forkAt: (seq: number) => void
+  /**
+   * Prose file-mention vocabulary for one closing message, from the optional
+   * {@link ChatFileMentions} service (resolved lazily per call, so composing
+   * the provider in or out takes effect live). Undefined when the service is
+   * absent or the turn produced nothing worth linking.
+   */
+  fileMentions: (owner: TurnTailOwnerProps) => MarkdownFileMentions | undefined
 }
 
 /** Full chat-view component props: runtime & the declared toolview/commandview holes' render share & store & injected & locale seat. */

packages/client/ui-conversation/src/client/index.ts

@@ -13,6 +13,7 @@ export type {
 export type { ToolCallBlock } from './contract/tool-call-model.ts'
 export type { ConversationKey } from './locales.ts'
 export type {
+  ChatFileMentions,
   ChatStore, ChatViewInjected, ChatViewSlotProps, CommandRowOwnerProps, CommandRowProps, ComposerBarInjected,
   ComposerChainProps, ConversationInjected,
   ConversationSessionHeaderInjected, ConversationSessionInjected, ConversationSlotProps,