feat(tui): Add inline $skill invocations with SKILL pill + pasteText support

packages/core/src/v1/session.ts

@@ -183,6 +183,20 @@ export const AgentPart = Schema.Struct({
 }).annotate({ identifier: "AgentPart" })
 export type AgentPart = Types.DeepMutable<Schema.Schema.Type<typeof AgentPart>>
 
+export const SkillPart = Schema.Struct({
+  ...partBase,
+  type: Schema.Literal("skill"),
+  name: Schema.String,
+  source: Schema.optional(
+    Schema.Struct({
+      value: Schema.String,
+      start: NonNegativeInt,
+      end: NonNegativeInt,
+    }),
+  ),
+}).annotate({ identifier: "SkillPart" })
+export type SkillPart = Types.DeepMutable<Schema.Schema.Type<typeof SkillPart>>
+
 export const CompactionPart = Schema.Struct({
   ...partBase,
   type: Schema.Literal("compaction"),
@@ -364,6 +378,7 @@ export const Part = Schema.Union([
   SnapshotPart,
   PatchPart,
   AgentPart,
+  SkillPart,
   RetryPart,
   CompactionPart,
 ]).annotate({ discriminator: "type", identifier: "Part" })
@@ -378,6 +393,7 @@ export type Part =
   | SnapshotPart
   | PatchPart
   | AgentPart
+  | SkillPart
   | RetryPart
   | CompactionPart
 
@@ -432,6 +448,20 @@ export const AgentPartInput = Schema.Struct({
 }).annotate({ identifier: "AgentPartInput" })
 export type AgentPartInput = Types.DeepMutable<Schema.Schema.Type<typeof AgentPartInput>>
 
+export const SkillPartInput = Schema.Struct({
+  id: Schema.optional(PartID),
+  type: Schema.Literal("skill"),
+  name: Schema.String,
+  source: Schema.optional(
+    Schema.Struct({
+      value: Schema.String,
+      start: NonNegativeInt,
+      end: NonNegativeInt,
+    }),
+  ),
+}).annotate({ identifier: "SkillPartInput" })
+export type SkillPartInput = Types.DeepMutable<Schema.Schema.Type<typeof SkillPartInput>>
+
 export const SubtaskPartInput = Schema.Struct({
   id: Schema.optional(PartID),
   type: Schema.Literal("subtask"),

packages/opencode/src/session/message-v2.ts

@@ -48,12 +48,14 @@ interface FetchDecompressionError extends Error {
 export const SYNTHETIC_ATTACHMENT_PROMPT = "Attached media from tool result:"
 export { isMedia }
 
+
 function truncateToolOutput(text: string, maxChars?: number) {
   if (!maxChars || text.length <= maxChars) return text
   const omitted = text.length - maxChars
   return `${text.slice(0, maxChars)}\n[Tool output truncated for compaction: omitted ${omitted} chars]`
 }
 
+
 export const Event = {
   Updated: SessionV1.Event.MessageUpdated,
   Removed: SessionV1.Event.MessageRemoved,

packages/opencode/src/session/prompt.ts

@@ -48,6 +48,7 @@ import { TaskTool, type TaskPromptOps } from "@/tool/task"
 import { SessionRunState } from "./run-state"
 import { RuntimeFlags } from "@/effect/runtime-flags"
 import { EventV2Bridge } from "@/event-v2-bridge"
+import { Skill } from "@/skill"
 import { Database } from "@opencode-ai/core/database/database"
 import { SessionEvent } from "@opencode-ai/core/session/event"
 import { SessionMessage } from "@opencode-ai/core/session/message"
@@ -121,6 +122,7 @@ export const layer = Layer.effect(
     const summary = yield* SessionSummary.Service
     const sys = yield* SystemPrompt.Service
     const llm = yield* LLM.Service
+    const skill = yield* Skill.Service
     const events = yield* EventV2Bridge.Service
     const flags = yield* RuntimeFlags.Service
     const database = yield* Database.Service
@@ -972,6 +974,21 @@ export const layer = Layer.effect(
           ]
         }
 
+        if (part.type === "skill") {
+          const resolved = yield* skill.get(part.name).pipe(Effect.orDie)
+          if (!resolved) return [{ ...part, messageID: info.id, sessionID: input.sessionID }]
+          return [
+            { ...part, messageID: info.id, sessionID: input.sessionID },
+            {
+              messageID: info.id,
+              sessionID: input.sessionID,
+              type: "text" as const,
+              synthetic: true,
+              text: `## Skill: ${resolved.name}\n\n${resolved.content.trim()}`,
+            },
+          ]
+        }
+
         return [{ ...part, messageID: info.id, sessionID: input.sessionID }]
       })
 
@@ -1561,6 +1578,7 @@ export const defaultLayer = Layer.suspend(() =>
         Database.defaultLayer,
         SystemPrompt.defaultLayer,
         LLM.defaultLayer,
+        Skill.defaultLayer,
         CrossSpawnSpawner.defaultLayer,
         RuntimeFlags.defaultLayer,
         EventV2Bridge.defaultLayer,
@@ -1591,6 +1609,7 @@ export const PromptInput = Schema.Struct({
       SessionV1.TextPartInput,
       SessionV1.FilePartInput,
       SessionV1.AgentPartInput,
+      SessionV1.SkillPartInput,
       SessionV1.SubtaskPartInput,
     ]).annotate({ discriminator: "type" }),
   ),
@@ -1689,6 +1708,7 @@ export const node = LayerNode.make(layer, [
   ToolRegistry.node,
   Truncate.node,
   Image.node,
+  Skill.node,
   CrossSpawnSpawner.node,
   Instruction.node,
   SessionRunState.node,

packages/opencode/test/session/prompt.test.ts

@@ -213,6 +213,7 @@ function makePrompt(input?: { processor?: "blocking" }) {
     Layer.provideMerge(deps),
   )
   return SessionPrompt.layer.pipe(
+    Layer.provide(Skill.defaultLayer),
     Layer.provide(SessionRevert.defaultLayer),
     Layer.provide(Image.defaultLayer),
     Layer.provide(summary),

packages/opencode/test/session/snapshot-tool-race.test.ts

@@ -158,6 +158,7 @@ function makeHttp() {
     TestLLMServer.layer,
     SessionSummary.defaultLayer,
     SessionPrompt.layer.pipe(
+      Layer.provide(Skill.defaultLayer),
       Layer.provide(SessionRevert.defaultLayer),
       Layer.provide(Image.defaultLayer),
       Layer.provide(SessionSummary.defaultLayer),

packages/plugin/src/tui.ts

@@ -5,6 +5,7 @@ import type {
   FilePart,
   LspStatus,
   McpStatus,
+  SkillPart,
   Todo,
   Message,
   Part,
@@ -186,6 +187,7 @@ export type TuiPromptInfo = {
   parts: (
     | Omit<FilePart, "id" | "messageID" | "sessionID">
     | Omit<AgentPart, "id" | "messageID" | "sessionID">
+    | Omit<SkillPart, "id" | "messageID" | "sessionID">
     | (Omit<TextPart, "id" | "messageID" | "sessionID"> & {
         source?: {
           text: {

packages/sdk/js/src/v2/gen/sdk.gen.ts

@@ -220,6 +220,7 @@ import type {
   SessionUnshareResponses,
   SessionUpdateErrors,
   SessionUpdateResponses,
+  SkillPartInput,
   SubtaskPartInput,
   SyncHistoryListErrors,
   SyncHistoryListResponses,
@@ -3735,7 +3736,7 @@ export class Session2 extends HeyApiClient {
       format?: OutputFormat
       system?: string
       variant?: string
-      parts?: Array<TextPartInput | FilePartInput | AgentPartInput | SubtaskPartInput>
+      parts?: Array<TextPartInput | FilePartInput | AgentPartInput | SkillPartInput | SubtaskPartInput>
     },
     options?: Options<never, ThrowOnError>,
   ) {
@@ -4088,7 +4089,7 @@ export class Session2 extends HeyApiClient {
       format?: OutputFormat
       system?: string
       variant?: string
-      parts?: Array<TextPartInput | FilePartInput | AgentPartInput | SubtaskPartInput>
+      parts?: Array<TextPartInput | FilePartInput | AgentPartInput | SkillPartInput | SubtaskPartInput>
     },
     options?: Options<never, ThrowOnError>,
   ) {

packages/sdk/js/src/v2/gen/types.gen.ts

@@ -594,6 +594,19 @@ export type AgentPart = {
   }
 }
 
+export type SkillPart = {
+  id: string
+  sessionID: string
+  messageID: string
+  type: "skill"
+  name: string
+  source?: {
+    value: string
+    start: number
+    end: number
+  }
+}
+
 export type RetryPart = {
   id: string
   sessionID: string
@@ -629,6 +642,7 @@ export type Part =
   | AgentPart
   | RetryPart
   | CompactionPart
+  | SkillPart
 
 export type Prompt = {
   text: string
@@ -2624,6 +2638,17 @@ export type AgentPartInput = {
   }
 }
 
+export type SkillPartInput = {
+  id?: string
+  type: "skill"
+  name: string
+  source?: {
+    value: string
+    start: number
+    end: number
+  }
+}
+
 export type SubtaskPartInput = {
   id?: string
   type: "subtask"

packages/tui/src/component/prompt/autocomplete.tsx

@@ -56,7 +56,7 @@ function extractLineRange(input: string) {
 
 export type AutocompleteRef = {
   onInput: (value: string) => void
-  visible: false | "@" | "/"
+  visible: false | "@" | "/" | "$"
 }
 
 export type AutocompleteOption = {
@@ -80,6 +80,8 @@ export function Autocomplete(props: {
   ref: (ref: AutocompleteRef) => void
   fileStyleId: number
   agentStyleId: number
+  skillStyleId: number
+  skills: () => Array<{ name: string; description?: string; content: string }> | undefined
   promptPartTypeId: () => number
 }) {
   const editor = useEditorContext()
@@ -353,7 +355,7 @@ export function Autocomplete(props: {
   )
 
   const mcpResources = createMemo(() => {
-    if (!store.visible || store.visible === "/") return []
+    if (store.visible !== "@") return []
 
     const options: AutocompleteOption[] = []
     const width = props.anchor().width - 4
@@ -410,6 +412,72 @@ export function Autocomplete(props: {
       )
   })
 
+  function insertSkill(name: string) {
+    const input = props.input()
+    const currentCursorOffset = input.cursorOffset
+
+    const charAfterCursor = displayCharAt(props.value, currentCursorOffset)
+    const needsSpace = charAfterCursor !== " "
+    const append = "$" + name + (needsSpace ? " " : "")
+
+    input.cursorOffset = store.index
+    const startCursor = input.logicalCursor
+    input.cursorOffset = currentCursorOffset
+    const endCursor = input.logicalCursor
+
+    input.deleteRange(startCursor.row, startCursor.col, endCursor.row, endCursor.col)
+    input.insertText(append)
+
+    const virtualText = "$" + name
+    const extmarkStart = store.index
+    const extmarkEnd = extmarkStart + Bun.stringWidth(virtualText)
+
+    const extmarkId = input.extmarks.create({
+      start: extmarkStart,
+      end: extmarkEnd,
+      virtual: true,
+      styleId: props.skillStyleId,
+      typeId: props.promptPartTypeId(),
+    })
+
+    props.setPrompt((draft) => {
+      if (draft.parts.some((p) => p.type === "skill" && p.name === name)) return
+      const partIndex = draft.parts.length
+      draft.parts.push({
+        type: "skill",
+        name,
+        source: {
+          start: extmarkStart,
+          end: extmarkEnd,
+          value: virtualText,
+        },
+      })
+      props.setExtmark(partIndex, extmarkId)
+    })
+  }
+
+  const skillList = createMemo(() => {
+    const results = (props.skills() ?? [])
+      .toSorted((a, b) => a.name.localeCompare(b.name))
+      .map(
+        (skill): AutocompleteOption => ({
+          display: skill.name,
+          value: skill.name,
+          description: skill.description,
+          onSelect: () => {
+            insertSkill(skill.name)
+          },
+        }),
+      )
+
+    const max = Math.max(0, ...results.map((item) => Bun.stringWidth(item.display)))
+    if (max === 0) return results
+    return results.map((item) => ({
+      ...item,
+      display: item.display.padEnd(max + 2),
+    }))
+  })
+
   const referenceAliases = createMemo(() =>
     syncV2.data.reference
       .filter((reference) => !reference.hidden)
@@ -468,6 +536,7 @@ export function Autocomplete(props: {
     const referenceMatchValue = referenceMatch()
     const agentsValue = agents()
     const referenceAliasesValue = referenceAliases()
+    const skillsValue = skillList()
     const commandsValue = commands()
     const searchValue = search()
 
@@ -481,7 +550,11 @@ export function Autocomplete(props: {
     // it shouldn't be additionally sorted by fuzzysort as it will loose the results
     const fileOptions: AutocompleteOption[] = store.visible === "@" ? filesValue || [] : []
     const nonFileOptions: AutocompleteOption[] =
-      store.visible === "@" ? [...referenceAliasesValue, ...agentsValue, ...mcpResources()] : [...commandsValue]
+      store.visible === "@"
+        ? [...referenceAliasesValue, ...agentsValue, ...mcpResources()]
+        : store.visible === "$"
+          ? skillsValue
+          : [...commandsValue]
 
     if (!searchValue) {
       return [...nonFileOptions, ...fileOptions]
@@ -630,7 +703,7 @@ export function Autocomplete(props: {
     ]),
   }))
 
-  function show(mode: "@" | "/") {
+  function show(mode: "@" | "/" | "$") {
     setStore({
       visible: mode,
       index: props.input().cursorOffset,
@@ -689,12 +762,18 @@ export function Autocomplete(props: {
           return
         }
 
-        // Check for "@" trigger - find the nearest "@" before cursor with no whitespace between
-        const idx = mentionTriggerIndex(value, offset)
-        if (idx !== undefined) {
-          show("@")
-          setStore("index", idx)
+        // Check for "@" and "$" triggers - find nearest before cursor with no whitespace between
+        const mentionIdx = mentionTriggerIndex(value, offset, "@")
+        const skillIdx = mentionTriggerIndex(value, offset, "$")
+        const idx = Math.max(mentionIdx ?? -1, skillIdx ?? -1)
+        if (idx === -1) return
+        if (skillIdx !== undefined && skillIdx === idx) {
+          const query = props.input().getTextRange(skillIdx, offset)
+          if (/^\$[A-Z_][A-Z0-9_]*$/.test(query) && !(props.skills() ?? []).some((skill) => `$${skill.name}` === query))
+            return
         }
+        show(skillIdx !== undefined && skillIdx === idx ? "$" : "@")
+        setStore("index", idx)
       },
     })
   })