test(core): simplify mutation lock coverage

packages/client/src/effect/api/api.ts

@@ -180,7 +180,6 @@ export type Endpoint5_12Input = {
   readonly text: string
   readonly files?: ReadonlyArray<PromptInput.FileAttachment> | undefined
   readonly agents?: ReadonlyArray<AgentAttachment> | undefined
-  readonly skills?: ReadonlyArray<PromptInput.SkillAttachment> | undefined
   readonly metadata?: { readonly [x: string]: unknown } | undefined
   readonly delivery?: "steer" | "queue" | undefined
   readonly resume?: boolean | undefined
@@ -197,7 +196,6 @@ export type Endpoint5_13Input = {
   readonly model?: Model.Ref | undefined
   readonly files?: ReadonlyArray<PromptInput.FileAttachment> | undefined
   readonly agents?: ReadonlyArray<AgentAttachment> | undefined
-  readonly skills?: ReadonlyArray<PromptInput.SkillAttachment> | undefined
   readonly delivery?: "steer" | "queue" | undefined
   readonly resume?: boolean | undefined
 }

packages/client/src/effect/generated/client.ts

@@ -412,7 +412,6 @@ const Endpoint5_12 = (raw: RawClient["server.session"]) => (input: Endpoint5_12I
         text: input["text"],
         files: input["files"],
         agents: input["agents"],
-        skills: input["skills"],
         metadata: input["metadata"],
         delivery: input["delivery"],
         resume: input["resume"],
@@ -435,7 +434,6 @@ const Endpoint5_13 = (raw: RawClient["server.session"]) => (input: Endpoint5_13I
         model: input["model"],
         files: input["files"],
         agents: input["agents"],
-        skills: input["skills"],
         delivery: input["delivery"],
         resume: input["resume"],
       },

packages/client/src/promise/generated/client.ts

@@ -615,7 +615,6 @@ export function make(options: ClientOptions) {
               text: input["text"],
               files: input["files"],
               agents: input["agents"],
-              skills: input["skills"],
               metadata: input["metadata"],
               delivery: input["delivery"],
               resume: input["resume"],
@@ -639,7 +638,6 @@ export function make(options: ClientOptions) {
               model: input["model"],
               files: input["files"],
               agents: input["agents"],
-              skills: input["skills"],
               delivery: input["delivery"],
               resume: input["resume"],
             },

packages/client/src/promise/generated/types.ts

@@ -1080,8 +1080,6 @@ export type PromptFileAttachment = {
 
 export type PromptAgentAttachment = { name: string; mention?: PromptMention }
 
-export type PromptSkillAttachment = { id: string; name: string; text: string; mention?: PromptMention }
-
 export type SessionMessageAssistantText = { type: "text"; text: string; state?: SessionMessageProviderState }
 
 export type SessionMessageAssistantReasoning = {
@@ -1567,7 +1565,6 @@ export type SessionMessageUser = {
   text: string
   files?: Array<PromptFileAttachment>
   agents?: Array<PromptAgentAttachment>
-  skills?: Array<PromptSkillAttachment>
   type: "user"
 }
 
@@ -1575,7 +1572,6 @@ export type SessionPendingUserData = {
   text: string
   files?: Array<PromptFileAttachment>
   agents?: Array<PromptAgentAttachment>
-  skills?: Array<PromptSkillAttachment>
   metadata?: { [x: string]: JsonValue }
 }
 
@@ -1583,7 +1579,6 @@ export type SessionPendingUserData1 = {
   text: string
   files?: Array<PromptFileAttachment>
   agents?: Array<PromptAgentAttachment>
-  skills?: Array<PromptSkillAttachment>
   metadata?: { [x: string]: any }
 }
 
@@ -2584,12 +2579,6 @@ export type SessionImportInput = {
             readonly name: string
             readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
           }>
-          readonly skills?: ReadonlyArray<{
-            readonly id: string
-            readonly name: string
-            readonly text: string
-            readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-          }>
           readonly type: "user"
         }
       | {
@@ -2835,12 +2824,6 @@ export type SessionImportInput = {
             readonly name: string
             readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
           }>
-          readonly skills?: ReadonlyArray<{
-            readonly id: string
-            readonly name: string
-            readonly text: string
-            readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-          }>
           readonly type: "user"
         }
       | {
@@ -3086,12 +3069,6 @@ export type SessionImportInput = {
             readonly name: string
             readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
           }>
-          readonly skills?: ReadonlyArray<{
-            readonly id: string
-            readonly name: string
-            readonly text: string
-            readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-          }>
           readonly type: "user"
         }
       | {
@@ -3343,10 +3320,6 @@ export type SessionPromptInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly metadata?: { readonly [x: string]: JsonValue }
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
@@ -3364,10 +3337,6 @@ export type SessionPromptInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly metadata?: { readonly [x: string]: JsonValue }
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
@@ -3385,10 +3354,6 @@ export type SessionPromptInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly metadata?: { readonly [x: string]: JsonValue }
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
@@ -3406,35 +3371,10 @@ export type SessionPromptInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly metadata?: { readonly [x: string]: JsonValue }
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["agents"]
-  readonly skills?: {
-    readonly id?: string | null
-    readonly text: string
-    readonly files?: ReadonlyArray<{
-      readonly uri: string
-      readonly name?: string
-      readonly description?: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
-    readonly agents?: ReadonlyArray<{
-      readonly name: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
-    readonly metadata?: { readonly [x: string]: JsonValue }
-    readonly delivery?: "steer" | "queue" | null
-    readonly resume?: boolean | null
-  }["skills"]
   readonly metadata?: {
     readonly id?: string | null
     readonly text: string
@@ -3448,10 +3388,6 @@ export type SessionPromptInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly metadata?: { readonly [x: string]: JsonValue }
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
@@ -3469,10 +3405,6 @@ export type SessionPromptInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly metadata?: { readonly [x: string]: JsonValue }
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
@@ -3490,10 +3422,6 @@ export type SessionPromptInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly metadata?: { readonly [x: string]: JsonValue }
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
@@ -3520,10 +3448,6 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["id"]
@@ -3543,10 +3467,6 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["command"]
@@ -3566,10 +3486,6 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["arguments"]
@@ -3589,10 +3505,6 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["agent"]
@@ -3612,10 +3524,6 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["model"]
@@ -3635,10 +3543,6 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["files"]
@@ -3658,36 +3562,9 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["agents"]
-  readonly skills?: {
-    readonly id?: string | null
-    readonly command: string
-    readonly arguments?: string | null
-    readonly agent?: string | null
-    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
-    readonly files?: ReadonlyArray<{
-      readonly uri: string
-      readonly name?: string
-      readonly description?: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
-    readonly agents?: ReadonlyArray<{
-      readonly name: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
-    readonly delivery?: "steer" | "queue" | null
-    readonly resume?: boolean | null
-  }["skills"]
   readonly delivery?: {
     readonly id?: string | null
     readonly command: string
@@ -3704,10 +3581,6 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["delivery"]
@@ -3727,10 +3600,6 @@ export type SessionCommandInput = {
       readonly name: string
       readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
     }>
-    readonly skills?: ReadonlyArray<{
-      readonly id: string
-      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
-    }>
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["resume"]

packages/core/src/file-mutation.ts

@@ -48,15 +48,13 @@ export const readText = Effect.fn("FileMutation.readText")(function* (files: Fil
   return Bom.decodeBytes((yield* files.read(target)).bytes)
 })
 
-export const syncTextBom = Effect.fn("FileMutation.syncTextBom")(function* (
-  files: Files,
-  target: string,
-  bom: boolean,
-) {
-  const synced = Bom.syncBytes((yield* files.read(target)).bytes, bom)
-  if (synced.bytes) yield* files.write(target, synced.bytes)
-  return synced.text
-})
+export const syncTextBom = Effect.fn("FileMutation.syncTextBom")((files: Files, target: string, bom: boolean) =>
+  Effect.gen(function* () {
+    const synced = Bom.syncBytes((yield* files.read(target)).bytes, bom)
+    if (synced.bytes) yield* files.write(target, synced.bytes)
+    return synced.text
+  }).pipe(Effect.uninterruptible),
+)
 
 /** Share transaction locks across Location graphs that address the same file. */
 const transactionLocks = KeyedMutex.makeUnsafe<string>()
@@ -70,15 +68,10 @@ const layer = Layer.effect(
   Service,
   Effect.gen(function* () {
     const environment = yield* Environment.Service
-    const locks = KeyedMutex.makeUnsafe<string>()
     const withLock: Interface["withLock"] = (targets) => (effect) =>
       [...new Set(targets.map(FSUtil.resolve))]
         .sort()
         .reduceRight((result, target) => transactionLocks.withLock(target)(result), effect)
-    const withTargetLock =
-      (target: Target) =>
-      <A, E, R>(effect: Effect.Effect<A, E, R>) =>
-        locks.withLock(target.absolute)(Effect.uninterruptible(effect))
 
     const writeResult = (target: Target, existed: boolean): WriteResult => ({
       operation: "write",
@@ -88,36 +81,32 @@ const layer = Layer.effect(
     })
 
     const write = Effect.fn("FileMutation.write")((input: WriteInput) =>
-      withTargetLock(input.target)(
-        Effect.gen(function* () {
-          const existed = yield* environment.files.stat(input.target.absolute).pipe(
-            Effect.as(true),
-            Effect.catchTag("Environment.NotFound", () => Effect.succeed(false)),
-          )
-          yield* environment.files.write(
-            input.target.absolute,
-            typeof input.content === "string" ? new TextEncoder().encode(input.content) : input.content,
-          )
-          return writeResult(input.target, existed)
-        }),
-      ),
+      Effect.gen(function* () {
+        const existed = yield* environment.files.stat(input.target.absolute).pipe(
+          Effect.as(true),
+          Effect.catchTag("Environment.NotFound", () => Effect.succeed(false)),
+        )
+        yield* environment.files.write(
+          input.target.absolute,
+          typeof input.content === "string" ? new TextEncoder().encode(input.content) : input.content,
+        )
+        return writeResult(input.target, existed)
+      }).pipe(Effect.uninterruptible),
     )
 
     const writeTextPreservingBom = Effect.fn("FileMutation.writeTextPreservingBom")((input: TextWriteInput) =>
-      withTargetLock(input.target)(
-        Effect.gen(function* () {
-          const next = Bom.split(input.content)
-          const current = yield* environment.files.read(input.target.absolute, { offset: 0, length: 3 }).pipe(
-            Effect.map((result) => result.bytes),
-            Effect.catchTag("Environment.NotFound", () => Effect.succeed(undefined)),
-          )
-          yield* environment.files.write(
-            input.target.absolute,
-            new TextEncoder().encode(Bom.join(next.text, Boolean(current && Bom.has(current)) || next.bom)),
-          )
-          return writeResult(input.target, current !== undefined)
-        }),
-      ),
+      Effect.gen(function* () {
+        const next = Bom.split(input.content)
+        const current = yield* environment.files.read(input.target.absolute, { offset: 0, length: 3 }).pipe(
+          Effect.map((result) => result.bytes),
+          Effect.catchTag("Environment.NotFound", () => Effect.succeed(undefined)),
+        )
+        yield* environment.files.write(
+          input.target.absolute,
+          new TextEncoder().encode(Bom.join(next.text, Boolean(current && Bom.has(current)) || next.bom)),
+        )
+        return writeResult(input.target, current !== undefined)
+      }).pipe(Effect.uninterruptible),
     )
 
     return Service.of({ withLock, write, writeTextPreservingBom })

packages/core/src/plugin/promise.ts

@@ -11,7 +11,6 @@ import { Provider } from "@opencode-ai/schema/provider"
 import { AbsolutePath } from "@opencode-ai/schema/schema"
 import { Session } from "@opencode-ai/schema/session"
 import { SessionMessage } from "@opencode-ai/schema/session-message"
-import { Skill } from "@opencode-ai/schema/skill"
 import { Workspace } from "@opencode-ai/schema/workspace"
 import { WebSearch } from "@opencode-ai/schema/websearch"
 import { DateTime, Effect, Scope, Stream } from "effect"
@@ -297,7 +296,6 @@ export function fromPromise(plugin: Plugin) {
                   ...input,
                   sessionID: Session.ID.make(input.sessionID),
                   id: input.id == null ? undefined : SessionMessage.ID.make(input.id),
-                  skills: input.skills?.map((skill) => ({ ...skill, id: Skill.ID.make(skill.id) })),
                   delivery: input.delivery ?? undefined,
                   resume: input.resume ?? undefined,
                 }),
@@ -312,7 +310,6 @@ export function fromPromise(plugin: Plugin) {
                   id: input.id == null ? undefined : SessionMessage.ID.make(input.id),
                   agent: input.agent == null ? undefined : Agent.ID.make(input.agent),
                   model: input.model == null ? undefined : model(input.model),
-                  skills: input.skills?.map((skill) => ({ ...skill, id: Skill.ID.make(skill.id) })),
                   arguments: input.arguments ?? undefined,
                   delivery: input.delivery ?? undefined,
                   resume: input.resume ?? undefined,

packages/core/src/session.ts

@@ -218,11 +218,10 @@ export interface Interface {
     text: string
     files?: PromptInput.Prompt["files"]
     agents?: PromptInput.Prompt["agents"]
-    skills?: PromptInput.Prompt["skills"]
     metadata?: Record<string, unknown>
     delivery?: SessionPending.Delivery
     resume?: boolean
-  }) => Effect.Effect<SessionPending.User, NotFoundError | PromptConflictError | AttachmentError | SkillNotFoundError>
+  }) => Effect.Effect<SessionPending.User, NotFoundError | PromptConflictError | AttachmentError>
   /** Generates text from current Session context without admitting input or mutating history. */
   readonly generate: (input: {
     sessionID: SessionSchema.ID
@@ -237,17 +236,11 @@ export interface Interface {
     model?: Model.Ref
     files?: PromptInput.Prompt["files"]
     agents?: PromptInput.Prompt["agents"]
-    skills?: PromptInput.Prompt["skills"]
     delivery?: SessionPending.Delivery
     resume?: boolean
   }) => Effect.Effect<
     SessionPending.User,
-    | NotFoundError
-    | PromptConflictError
-    | AttachmentError
-    | SkillNotFoundError
-    | Command.NotFoundError
-    | Command.EvaluationError
+    NotFoundError | PromptConflictError | AttachmentError | Command.NotFoundError | Command.EvaluationError
   >
   readonly shell: (input: {
     id?: Event.ID
@@ -574,11 +567,9 @@ const layer = Layer.effect(
             // Resolved lazily so prompt admission only boots location services when an
             // image attachment actually needs the resizer.
             const image = Image.Service.pipe(Effect.provide(locations.get(session.location)))
-            const skills = Skill.Service.pipe(Effect.provide(locations.get(session.location)))
             const prompt = yield* resolvePrompt(
-              { text: input.text, files: input.files, agents: input.agents, skills: input.skills },
+              { text: input.text, files: input.files, agents: input.agents },
               image,
-              skills,
             ).pipe(Effect.provideService(FSUtil.Service, fs))
             const messageID = input.id ?? SessionMessage.ID.create()
             const admittedInput = SessionPending.Message.make({
@@ -644,7 +635,6 @@ const layer = Layer.effect(
           text: evaluated.text,
           files: input.files,
           agents: input.agents,
-          skills: input.skills,
           delivery: input.delivery,
           resume: input.resume,
         })
@@ -907,28 +897,12 @@ function synthesizeTerminalShellInfo(started: ShellSchema.Info): ShellSchema.Inf
 const resolvePrompt = Effect.fn("Session.resolvePrompt")(function* (
   input: PromptInput.Prompt,
   image: Effect.Effect<Image.Interface>,
-  skills: Effect.Effect<Skill.Interface>,
 ) {
   const fs = yield* FSUtil.Service
   const files = input.files
     ? yield* Effect.forEach(input.files, (file) => materializeAttachment(fs, file, image), { concurrency: 8 })
     : undefined
-  const requested = input.skills
-  const selected = yield* Effect.gen(function* () {
-    if (!requested?.length) return undefined
-    const available = yield* (yield* skills).list()
-    return yield* Effect.forEach(requested, (attachment) => {
-      const skill = available.find((item) => item.id === attachment.id)
-      if (!skill) return Effect.fail(new SkillNotFoundError({ skill: attachment.id }))
-      return Effect.succeed({
-        id: skill.id,
-        name: skill.name,
-        text: Skill.toModelOutput(skill, []),
-        mention: attachment.mention,
-      })
-    })
-  })
-  return Prompt.make({ text: input.text, agents: input.agents, files, skills: selected?.length ? selected : undefined })
+  return Prompt.make({ text: input.text, agents: input.agents, files })
 })
 
 const MAX_ATTACHMENT_BYTES = 20 * 1024 * 1024

packages/core/src/session/compaction.ts

@@ -124,8 +124,7 @@ const serialize = (message: SessionMessage.Info) => {
         (file) =>
           `[Attached ${file.mime}: ${file.name ?? (file.source.type === "uri" ? file.source.uri : "inline attachment")}]`,
       ) ?? []
-    const skills = message.skills?.map((skill) => `[Attached skill: ${skill.name}]\n${skill.text}`) ?? []
-    return [`[User]: ${message.text}`, ...skills, ...files].join("\n")
+    return [`[User]: ${message.text}`, ...files].join("\n")
   }
   if (message.type === "assistant") {
     return message.content

packages/core/src/session/projector.ts

@@ -453,7 +453,6 @@ const layer = Layer.effectDiscard(
                 text: input.data.text,
                 files: input.data.files,
                 agents: input.data.agents,
-                skills: input.data.skills,
                 time: { created: event.created },
               }
             : {

packages/core/src/session/runner/to-llm-message.ts

@@ -184,7 +184,6 @@ function toLLMMessage(message: SessionMessage.Info, model: Model.Ref, providerMe
       return []
     case "user":
       const content = [
-        ...(message.skills ?? []).map((skill) => Message.text(skill.text)),
         ...(message.text === "" ? [] : [Message.text(message.text)]),
         ...(message.files ?? []).flatMap(attachmentContent),
       ]

packages/core/src/session/transfer.ts

@@ -2,7 +2,6 @@ export * as SessionTransfer from "./transfer"
 
 import { SessionTransfer } from "@opencode-ai/schema/session-transfer"
 import { Tool } from "@opencode-ai/schema/tool"
-import { Skill } from "@opencode-ai/schema/skill"
 import { eq, isNotNull, isNull, ne, or } from "drizzle-orm"
 import { Context, DateTime, Effect, Layer, Schema } from "effect"
 import path from "path"
@@ -220,14 +219,6 @@ function sanitizeMessage(message: SessionMessage.Info): SessionMessage.Info {
           ? { ...agent.mention, text: redact("agent-mention", String(index), agent.mention.text) }
           : undefined,
       })),
-      skills: message.skills?.map((skill, index) => ({
-        ...skill,
-        name: Skill.Name.make(redact("skill-name", String(index), skill.name)),
-        text: redact("skill", String(index), skill.text),
-        mention: skill.mention
-          ? { ...skill.mention, text: redact("skill-mention", String(index), skill.mention.text) }
-          : undefined,
-      })),
     }
   if (message.type === "synthetic")
     return {

packages/core/src/skill.ts

@@ -38,25 +38,6 @@ export { Event } from "@opencode-ai/schema/skill"
 export const available = (skills: ReadonlyArray<Info>, agent: Agent.Info) =>
   skills.filter((skill) => Permission.evaluate("skill", skill.id, agent.permissions).effect !== "deny")
 
-export const toModelOutput = (skill: Info, files: ReadonlyArray<string>) => {
-  const directory = path.dirname(skill.location)
-  return [
-    `<skill_content name="${skill.name}">`,
-    `# Skill: ${skill.name}`,
-    "",
-    skill.content.trim(),
-    "",
-    `Base directory for this skill: ${directory}`,
-    "Relative paths in this skill (e.g., scripts/, reference/) are relative to this base directory.",
-    "Note: file list is sampled.",
-    "",
-    "<skill_files>",
-    ...files.map((file) => `<file>${file}</file>`),
-    "</skill_files>",
-    "</skill_content>",
-  ].join("\n")
-}
-
 const Frontmatter = Schema.Struct({
   name: Schema.String.pipe(Schema.optional),
   description: Schema.String.pipe(Schema.optional),

packages/core/src/tool/plugin/skill.ts

@@ -26,6 +26,25 @@ export const description = [
   "The skill ID must match one of the available skills in the instructions.",
 ].join("\n")
 
+export const toModelOutput = (skill: Skill.Info, files: ReadonlyArray<string>) => {
+  const directory = path.dirname(skill.location)
+  return [
+    `<skill_content name="${skill.name}">`,
+    `# Skill: ${skill.name}`,
+    "",
+    skill.content.trim(),
+    "",
+    `Base directory for this skill: ${directory}`,
+    "Relative paths in this skill (e.g., scripts/, reference/) are relative to this base directory.",
+    "Note: file list is sampled.",
+    "",
+    "<skill_files>",
+    ...files.map((file) => `<file>${file}</file>`),
+    "</skill_files>",
+    "</skill_content>",
+  ].join("\n")
+}
+
 const unableToLoad = (name: string, error?: unknown) =>
   new ToolFailure({ message: `Unable to load skill ${name}`, error })
 
@@ -69,7 +88,7 @@ export const Plugin = {
                   return {
                     name: skill.name,
                     directory,
-                    output: Skill.toModelOutput(skill, files),
+                    output: toModelOutput(skill, files),
                   }
                 }).pipe(Effect.mapError((error) => unableToLoad(input.id, error)))
               }).pipe(

packages/core/src/tool/plugin/write.ts

@@ -69,34 +69,43 @@ export const Plugin = {
                 id: context.id,
               }
               const target = yield* mutation.resolve({ path: input.path, kind: "file" })
-              const external = target.externalDirectory
-              if (external)
-                yield* permission.assert({
-                  ...LocationMutation.externalDirectoryPermission(external),
-                  sessionID: context.sessionID,
-                  agent: context.agent,
-                  source,
-                })
-              const current = yield* FileMutation.readText(environment.files, target.absolute).pipe(
-                Effect.catchTag("Environment.NotFound", () => Effect.succeed(undefined)),
+              return yield* fileMutation.withLock([target.absolute])(
+                Effect.gen(function* () {
+                  const external = target.externalDirectory
+                  if (external)
+                    yield* permission.assert({
+                      ...LocationMutation.externalDirectoryPermission(external),
+                      sessionID: context.sessionID,
+                      agent: context.agent,
+                      source,
+                    })
+                  const current = yield* FileMutation.readText(environment.files, target.absolute).pipe(
+                    Effect.catchTag("Environment.NotFound", () => Effect.succeed(undefined)),
+                  )
+                  const next = Bom.split(input.content)
+                  const preview = fileDiff(
+                    target.resource,
+                    current?.text ?? "",
+                    next.text,
+                    current ? "modified" : "added",
+                  )
+                  yield* permission.assert({
+                    action: "edit",
+                    resources: [target.resource],
+                    save: ["*"],
+                    metadata: { files: [preview] },
+                    sessionID: context.sessionID,
+                    agent: context.agent,
+                    source,
+                  })
+                  const result = yield* fileMutation.writeTextPreservingBom({ target, content: input.content })
+                  const bom = (yield* FileMutation.readText(environment.files, target.absolute)).bom
+                  if (yield* formatter.file(target.absolute)) {
+                    yield* FileMutation.syncTextBom(environment.files, target.absolute, bom)
+                  }
+                  return result
+                }),
               )
-              const next = Bom.split(input.content)
-              const preview = fileDiff(target.resource, current?.text ?? "", next.text, current ? "modified" : "added")
-              yield* permission.assert({
-                action: "edit",
-                resources: [target.resource],
-                save: ["*"],
-                metadata: { files: [preview] },
-                sessionID: context.sessionID,
-                agent: context.agent,
-                source,
-              })
-              const result = yield* fileMutation.writeTextPreservingBom({ target, content: input.content })
-              const bom = (yield* FileMutation.readText(environment.files, target.absolute)).bom
-              if (yield* formatter.file(target.absolute)) {
-                yield* FileMutation.syncTextBom(environment.files, target.absolute, bom)
-              }
-              return result
             }).pipe(
               Effect.map((output) => ({ output, content: toModelOutput(output) })),
               Effect.mapError((error) => new ToolFailure({ message: `Unable to write ${input.path}`, error })),

packages/core/test/file-mutation.test.ts

@@ -109,49 +109,6 @@ describe("FileMutation", () => {
     ),
   )
 
-  it.live("serializes concurrent writes to the same absolute target", () =>
-    withTmp((directory) =>
-      Effect.gen(function* () {
-        const targetPath = path.join(directory, "shared.txt")
-        yield* Effect.promise(() => fs.writeFile(targetPath, "initial"))
-        const firstStarted = yield* Deferred.make<void>()
-        const releaseFirst = yield* Deferred.make<void>()
-        const secondStarted = yield* Deferred.make<void>()
-        let writes = 0
-        const filesystem = instrumentWrites((write) =>
-          Effect.gen(function* () {
-            writes++
-            if (writes === 1) {
-              yield* Deferred.succeed(firstStarted, undefined)
-              yield* Deferred.await(releaseFirst)
-            } else {
-              yield* Deferred.succeed(secondStarted, undefined)
-            }
-            yield* write
-          }),
-        )
-
-        yield* Effect.gen(function* () {
-          const mutation = yield* LocationMutation.Service
-          const files = yield* FileMutation.Service
-          const firstPlan = yield* mutation.resolve({ path: "shared.txt" })
-          const secondPlan = yield* mutation.resolve({ path: "shared.txt" })
-          const first = yield* files.write({ target: firstPlan, content: "first" }).pipe(Effect.forkChild)
-          yield* Deferred.await(firstStarted)
-          const second = yield* files.write({ target: secondPlan, content: "second" }).pipe(Effect.forkChild)
-          yield* Effect.yieldNow
-          expect(yield* Deferred.isDone(secondStarted)).toBe(false)
-
-          yield* Deferred.succeed(releaseFirst, undefined)
-          yield* Deferred.await(secondStarted)
-          yield* Fiber.join(first)
-          yield* Fiber.join(second)
-          expect(yield* Effect.promise(() => fs.readFile(targetPath, "utf8"))).toBe("second")
-        }).pipe(provide(directory, filesystem))
-      }),
-    ),
-  )
-
   it.live("shares transaction locks across Location service instances", () =>
     withTmp((directory) =>
       Effect.gen(function* () {
@@ -202,56 +159,4 @@ describe("FileMutation", () => {
       }).pipe(provide(directory)),
     ),
   )
-
-  it.live("allows distinct absolute targets to proceed independently", () =>
-    withTmp((directory) =>
-      Effect.gen(function* () {
-        const firstStarted = yield* Deferred.make<void>()
-        const releaseFirst = yield* Deferred.make<void>()
-        const secondFinished = yield* Deferred.make<void>()
-        const secondPath = path.join(directory, "second.txt")
-        let writes = 0
-        const filesystem = instrumentWrites((write) =>
-          ++writes === 1
-            ? Deferred.succeed(firstStarted, undefined).pipe(
-                Effect.andThen(Deferred.await(releaseFirst)),
-                Effect.andThen(write),
-              )
-            : write.pipe(Effect.andThen(Deferred.succeed(secondFinished, undefined))),
-        )
-
-        yield* Effect.gen(function* () {
-          const mutation = yield* LocationMutation.Service
-          const files = yield* FileMutation.Service
-          const firstPlan = yield* mutation.resolve({ path: "first.txt" })
-          const secondPlan = yield* mutation.resolve({ path: "second.txt" })
-          const first = yield* files.write({ target: firstPlan, content: "first" }).pipe(Effect.forkChild)
-          yield* Deferred.await(firstStarted)
-          const second = yield* files.write({ target: secondPlan, content: "second" }).pipe(Effect.forkChild)
-          yield* Deferred.await(secondFinished)
-          expect(yield* Effect.promise(() => fs.readFile(secondPath, "utf8"))).toBe("second")
-
-          yield* Deferred.succeed(releaseFirst, undefined)
-          yield* Fiber.join(first)
-          yield* Fiber.join(second)
-        }).pipe(provide(directory, filesystem))
-      }),
-    ),
-  )
 })
-
-function instrumentWrites(run: <E>(write: Effect.Effect<void, E>, target: string) => Effect.Effect<void, E>) {
-  return Layer.effect(
-    Environment.Service,
-    Effect.gen(function* () {
-      const environment = yield* Environment.Service
-      return Environment.Service.of({
-        ...environment,
-        files: {
-          ...environment.files,
-          write: (target, content) => run(environment.files.write(target, content), target),
-        },
-      })
-    }),
-  ).pipe(Layer.provide(LayerNode.compile(Environment.node)))
-}

packages/core/test/session-runner-message.test.ts

@@ -3,8 +3,7 @@ import { Message } from "@opencode-ai/ai"
 import { Model } from "@opencode-ai/core/model"
 import { Provider } from "@opencode-ai/core/provider"
 import { SessionMessage } from "@opencode-ai/core/session/message"
-import { AgentAttachment, Base64, FileAttachment, SkillAttachment } from "@opencode-ai/schema/prompt"
-import { Skill } from "@opencode-ai/schema/skill"
+import { AgentAttachment, Base64, FileAttachment } from "@opencode-ai/schema/prompt"
 import { toLLMMessages } from "@opencode-ai/core/session/runner/to-llm-message"
 import { Agent } from "@opencode-ai/core/agent"
 import { Shell } from "@opencode-ai/schema/shell"
@@ -185,40 +184,6 @@ Recent work
     })
   })
 
-  test("lowers selected skill instructions with the original user prompt", () => {
-    const messages = toLLMMessages(
-      [
-        SessionMessage.User.make({
-          id: id("user-skill"),
-          type: "user",
-          text: "Design this API",
-          skills: [
-            SkillAttachment.make({
-              id: Skill.ID.make("api-design"),
-              name: Skill.Name.make("API design"),
-              text: "Start from the ideal call site.",
-            }),
-          ],
-          time: { created },
-        }),
-      ],
-      model,
-    )
-
-    expect(messages).toHaveLength(1)
-    expect(messages[0]).toMatchObject({
-      id: id("user-skill"),
-      role: "user",
-      content: [
-        {
-          type: "text",
-          text: "Start from the ideal call site.",
-        },
-        { type: "text", text: "Design this API" },
-      ],
-    })
-  })
-
   test("decodes inline text attachment content", () => {
     const messages = toLLMMessages(
       [

packages/core/test/session-skill.test.ts

@@ -15,7 +15,6 @@ import { SessionExecution } from "@opencode-ai/core/session/execution"
 import { SessionMessage } from "@opencode-ai/core/session/message"
 import { SessionProjector } from "@opencode-ai/core/session/projector"
 import { SessionStore } from "@opencode-ai/core/session/store"
-import { SessionPending } from "@opencode-ai/core/session/pending"
 import { Skill } from "@opencode-ai/core/skill"
 import { testEffect } from "./lib/effect"
 
@@ -56,41 +55,6 @@ const it = testEffect(
 )
 
 describe("Session.skill", () => {
-  it.effect("attaches a resolved skill snapshot to a normal prompt", () =>
-    Effect.gen(function* () {
-      const sessions = yield* Session.Service
-      const database = yield* Database.Service
-      const bus = yield* Bus.Service
-      const session = yield* sessions.create({ location })
-      const id = SessionMessage.ID.make("msg_skill_attachment")
-
-      yield* sessions.prompt({
-        id,
-        sessionID: session.id,
-        text: "Apply this guidance",
-        skills: [{ id: Skill.ID.make("effect"), mention: { start: 20, end: 27, text: "/effect" } }],
-        resume: false,
-      })
-      yield* SessionPending.promote(database.db, bus, session.id, "steer")
-
-      expect(yield* sessions.messages({ sessionID: session.id })).toContainEqual(
-        expect.objectContaining({
-          id,
-          type: "user",
-          text: "Apply this guidance",
-          skills: [
-            {
-              id: "effect",
-              name: "Effect",
-              text: expect.stringContaining("Use Effect"),
-              mention: { start: 20, end: 27, text: "/effect" },
-            },
-          ],
-        }),
-      )
-    }),
-  )
-
   it.effect("projects the caller-supplied message ID", () =>
     Effect.gen(function* () {
       const sessions = yield* Session.Service

packages/core/test/tool-skill.test.ts

@@ -108,9 +108,9 @@ describe("SkillTool", () => {
               }),
             ).toMatchObject({
               status: "completed",
-              content: [{ type: "text", text: Skill.toModelOutput(info, [reference]) }],
+              content: [{ type: "text", text: SkillTool.toModelOutput(info, [reference]) }],
             })
-            expect(Skill.toModelOutput(info, [reference])).toContain(`Base directory for this skill: ${directory}`)
+            expect(SkillTool.toModelOutput(info, [reference])).toContain(`Base directory for this skill: ${directory}`)
             expect(
               yield* executeTool(registry, {
                 sessionID,
@@ -119,8 +119,8 @@ describe("SkillTool", () => {
               }),
             ).toEqual({
               status: "completed",
-              output: { name: "Effect", directory, output: Skill.toModelOutput(info, [reference]) },
-              content: [{ type: "text", text: Skill.toModelOutput(info, [reference]) }],
+              output: { name: "Effect", directory, output: SkillTool.toModelOutput(info, [reference]) },
+              content: [{ type: "text", text: SkillTool.toModelOutput(info, [reference]) }],
               metadata: { name: "Effect", directory },
             })
             expect(assertions).toMatchObject([
@@ -171,7 +171,7 @@ describe("SkillTool", () => {
               }),
             ).toMatchObject({
               status: "completed",
-              content: [{ type: "text", text: Skill.toModelOutput(flat, []) }],
+              content: [{ type: "text", text: SkillTool.toModelOutput(flat, []) }],
             })
           }).pipe(Effect.provide(skillToolLayer))
         }),

packages/core/test/tool-write.test.ts

@@ -1,7 +1,7 @@
 import fs from "fs/promises"
 import path from "path"
 import { describe, expect } from "bun:test"
-import { Effect, Layer } from "effect"
+import { Deferred, Effect, Fiber, Layer } from "effect"
 import { FileMutation } from "@opencode-ai/core/file-mutation"
 import { Formatter } from "@opencode-ai/core/formatter"
 import { AppNodeBuilder } from "@opencode-ai/core/effect/app-node-builder"
@@ -13,6 +13,7 @@ import { Permission } from "@opencode-ai/core/permission"
 import { AbsolutePath } from "@opencode-ai/core/schema"
 import { Session } from "@opencode-ai/core/session"
 import { Tool } from "@opencode-ai/core/tool"
+import { EditTool } from "@opencode-ai/core/tool/plugin/edit"
 import { WriteTool } from "@opencode-ai/core/tool/plugin/write"
 import { location } from "./fixture/location"
 import { tmpdir } from "./fixture/tmpdir"
@@ -26,10 +27,25 @@ const writeToolNode = makeLocationNode({
   deps: [Tool.node, LocationMutation.node, FileMutation.node, Environment.node, Formatter.node, Permission.node],
 })
 
+const editToolNode = makeLocationNode({
+  name: "test/edit-tool-plugin",
+  layer: Layer.effectDiscard(registerToolPlugin(EditTool.Plugin)),
+  deps: [
+    Tool.node,
+    LocationMutation.node,
+    FileMutation.node,
+    Environment.node,
+    Formatter.node,
+    Location.node,
+    Permission.node,
+  ],
+})
+
 const sessionID = Session.ID.make("ses_write_tool_test")
 const assertions: Permission.AssertInput[] = []
 const writes: string[] = []
 let formatFile = (_target: string): Effect.Effect<boolean> => Effect.succeed(false)
+let afterPermission = (_input: Permission.AssertInput): Effect.Effect<void> => Effect.void
 let denyAction: string | undefined
 
 const permission = Layer.succeed(
@@ -37,6 +53,7 @@ const permission = Layer.succeed(
   Permission.Service.of({
     assert: (input) =>
       Effect.sync(() => assertions.push(input)).pipe(
+        Effect.andThen(Effect.suspend(() => afterPermission(input))),
         Effect.andThen(
           input.action === denyAction
             ? Effect.fail(
@@ -65,6 +82,7 @@ const reset = () => {
   assertions.length = 0
   writes.length = 0
   formatFile = () => Effect.succeed(false)
+  afterPermission = () => Effect.void
   denyAction = undefined
 }
 
@@ -83,7 +101,11 @@ const environment = Layer.effect(
   }),
 ).pipe(Layer.provide(LayerNode.compile(Environment.node)))
 
-const withTool = <A, E, R>(directory: string, body: (registry: Tool.Interface) => Effect.Effect<A, E, R>) => {
+const withTool = <A, E, R>(
+  directory: string,
+  body: (registry: Tool.Interface) => Effect.Effect<A, E, R>,
+  options?: { edit?: boolean },
+) => {
   const activeLocation = Layer.succeed(
     Location.Service,
     Location.Service.of(location({ directory: AbsolutePath.make(directory) })),
@@ -93,7 +115,13 @@ const withTool = <A, E, R>(directory: string, body: (registry: Tool.Interface) =
   }).pipe(
     Effect.provide(
       AppNodeBuilder.build(
-        LayerNode.group([Tool.node, Tool.node, LocationMutation.node, FileMutation.node, writeToolNode]),
+        LayerNode.group([
+          Tool.node,
+          LocationMutation.node,
+          FileMutation.node,
+          writeToolNode,
+          ...(options?.edit ? [editToolNode] : []),
+        ]),
         [
           [Environment.node, environment],
           [Location.node, activeLocation],
@@ -111,6 +139,12 @@ const call = (input: typeof WriteTool.Input.Type, id = "call-write") => ({
   call: { type: "tool-call" as const, id, name: "write", input },
 })
 
+const editCall = (input: typeof EditTool.Input.Type, id = "call-edit") => ({
+  sessionID,
+  ...toolIdentity,
+  call: { type: "tool-call" as const, id, name: "edit", input },
+})
+
 const it = testEffect(Layer.empty)
 
 describe("WriteTool", () => {
@@ -420,4 +454,59 @@ describe("WriteTool", () => {
         ),
     ),
   )
+
+  it.live("serializes write and edit transactions across Location service instances", () =>
+    Effect.acquireUseRelease(
+      Effect.promise(() => tmpdir()),
+      (tmp) => {
+        reset()
+        const target = path.join(tmp.path, "shared.txt")
+        return Effect.gen(function* () {
+          yield* Effect.promise(() => fs.writeFile(target, "initial"))
+          const formatting = yield* Deferred.make<void>()
+          const releaseFormatting = yield* Deferred.make<void>()
+          const editApproved = yield* Deferred.make<void>()
+          let formats = 0
+          formatFile = () =>
+            ++formats === 1
+              ? Deferred.succeed(formatting, undefined).pipe(
+                  Effect.andThen(Deferred.await(releaseFormatting)),
+                  Effect.as(false),
+                )
+              : Effect.succeed(false)
+          afterPermission = (input) =>
+            input.source?.id === "call-serialized-edit" && input.action === "edit"
+              ? Deferred.succeed(editApproved, undefined).pipe(Effect.asVoid)
+              : Effect.void
+
+          const write = yield* withTool(
+            tmp.path,
+            (registry) =>
+              executeTool(registry, call({ path: "shared.txt", content: "before" }, "call-serialized-write")),
+            { edit: true },
+          ).pipe(Effect.forkChild)
+          yield* Deferred.await(formatting)
+          const edit = yield* withTool(
+            tmp.path,
+            (registry) =>
+              executeTool(
+                registry,
+                editCall({ path: "shared.txt", oldString: "before", newString: "after" }, "call-serialized-edit"),
+              ),
+            { edit: true },
+          ).pipe(Effect.forkChild)
+          yield* Effect.yieldNow
+          expect(yield* Deferred.isDone(editApproved)).toBe(false)
+
+          yield* Deferred.succeed(releaseFormatting, undefined)
+          expect((yield* Fiber.join(write)).status).toBe("completed")
+          expect((yield* Fiber.join(edit)).status).toBe("completed")
+          expect(yield* Deferred.isDone(editApproved)).toBe(true)
+          expect(yield* Effect.promise(() => fs.readFile(target, "utf8"))).toBe("after")
+        })
+      },
+      (tmp) => Effect.promise(() => tmp[Symbol.asyncDispose]()),
+    ),
+  )
+
 })

packages/protocol/src/groups/session.ts

@@ -347,7 +347,6 @@ export const makeSessionGroup = <I extends HttpApiMiddleware.AnyId, S>(sessionLo
           model: Model.Ref.pipe(Schema.optional),
           files: PromptInput.Prompt.fields.files,
           agents: PromptInput.Prompt.fields.agents,
-          skills: PromptInput.Prompt.fields.skills,
           delivery: SessionPending.Delivery.pipe(Schema.optional),
           resume: Schema.Boolean.pipe(Schema.optional),
         }),

packages/schema/src/prompt-input.ts

@@ -3,7 +3,6 @@ export * as PromptInput from "./prompt-input.js"
 import { Schema } from "effect"
 import { AgentAttachment, PromptMention } from "./prompt.js"
 import { optional, statics } from "./schema.js"
-import { Skill } from "./skill.js"
 
 export interface FileAttachment extends Schema.Schema.Type<typeof FileAttachment> {}
 export const FileAttachment = Schema.Struct({
@@ -20,15 +19,8 @@ export const FileAttachment = Schema.Struct({
   )
 
 export interface Prompt extends Schema.Schema.Type<typeof Prompt> {}
-export interface SkillAttachment extends Schema.Schema.Type<typeof SkillAttachment> {}
-export const SkillAttachment = Schema.Struct({
-  id: Skill.ID,
-  mention: PromptMention.pipe(optional),
-}).annotate({ identifier: "PromptInput.SkillAttachment" })
-
 export const Prompt = Schema.Struct({
   text: Schema.String,
   files: Schema.Array(FileAttachment).pipe(optional),
   agents: Schema.Array(AgentAttachment).pipe(optional),
-  skills: Schema.Array(SkillAttachment).pipe(optional),
 }).annotate({ identifier: "PromptInput" })

packages/schema/src/prompt.ts

@@ -1,7 +1,6 @@
 import { Schema } from "effect"
 import { optional } from "./schema.js"
 import { statics } from "./schema.js"
-import { Skill } from "./skill.js"
 
 export interface PromptMention extends Schema.Schema.Type<typeof PromptMention> {}
 export const PromptMention = Schema.Struct({
@@ -53,31 +52,21 @@ export const AgentAttachment = Schema.Struct({
   mention: PromptMention.pipe(optional),
 }).annotate({ identifier: "Prompt.AgentAttachment" })
 
-export interface SkillAttachment extends Schema.Schema.Type<typeof SkillAttachment> {}
-export const SkillAttachment = Schema.Struct({
-  id: Skill.ID,
-  name: Skill.Name,
-  text: Schema.String,
-  mention: PromptMention.pipe(optional),
-}).annotate({ identifier: "Prompt.SkillAttachment" })
-
 export interface Prompt extends Schema.Schema.Type<typeof Prompt> {}
 export const Prompt = Schema.Struct({
   text: Schema.String,
   files: Schema.Array(FileAttachment).pipe(optional),
   agents: Schema.Array(AgentAttachment).pipe(optional),
-  skills: Schema.Array(SkillAttachment).pipe(optional),
 })
   .annotate({ identifier: "Prompt" })
   .pipe(
     statics((schema) => ({
       equivalence: Schema.toEquivalence(schema),
-      fromUserMessage: (input: Pick<Prompt, "text" | "files" | "agents" | "skills">) =>
+      fromUserMessage: (input: Pick<Prompt, "text" | "files" | "agents">) =>
         schema.make({
           text: input.text,
           ...(input.files === undefined ? {} : { files: input.files }),
           ...(input.agents === undefined ? {} : { agents: input.agents }),
-          ...(input.skills === undefined ? {} : { skills: input.skills }),
         }),
     })),
   )

packages/schema/src/session-message.ts

@@ -58,7 +58,6 @@ export const User = Schema.Struct({
   text: Prompt.fields.text,
   files: Prompt.fields.files,
   agents: Prompt.fields.agents,
-  skills: Prompt.fields.skills,
   type: Schema.tag("user"),
 }).annotate({ identifier: "Session.Message.User" })
 

packages/server/src/handlers/session.ts

@@ -313,7 +313,6 @@ export const SessionHandler = HttpApiBuilder.group(Api, "server.session", (handl
                 text: ctx.payload.text,
                 files: ctx.payload.files,
                 agents: ctx.payload.agents,
-                skills: ctx.payload.skills,
                 metadata: ctx.payload.metadata,
                 delivery: ctx.payload.delivery,
                 resume: ctx.payload.resume,
@@ -338,9 +337,6 @@ export const SessionHandler = HttpApiBuilder.group(Api, "server.session", (handl
                 Effect.catchTag("Session.AttachmentError", (error) =>
                   Effect.fail(new InvalidRequestError({ message: error.message, field: "files" })),
                 ),
-                Effect.catchTag("Session.SkillNotFoundError", (error) =>
-                  Effect.fail(new InvalidRequestError({ message: `Skill not found: ${error.skill}`, field: "skills" })),
-                ),
               ),
           }
         }),
@@ -359,7 +355,6 @@ export const SessionHandler = HttpApiBuilder.group(Api, "server.session", (handl
                 model: ctx.payload.model,
                 files: ctx.payload.files,
                 agents: ctx.payload.agents,
-                skills: ctx.payload.skills,
                 delivery: ctx.payload.delivery,
                 resume: ctx.payload.resume,
               })
@@ -399,9 +394,6 @@ export const SessionHandler = HttpApiBuilder.group(Api, "server.session", (handl
                 Effect.catchTag("Session.AttachmentError", (error) =>
                   Effect.fail(new InvalidRequestError({ message: error.message, field: "files" })),
                 ),
-                Effect.catchTag("Session.SkillNotFoundError", (error) =>
-                  Effect.fail(new InvalidRequestError({ message: `Skill not found: ${error.skill}`, field: "skills" })),
-                ),
               ),
           }
         }),

packages/theme/src/tui/syntax.ts

@@ -12,7 +12,6 @@ export function generateSyntax(theme: ResolvedThemeTokens, mode: Mode) {
     rule(["prompt"], theme.hue.accent[step]),
     rule(["extmark.file"], feedback.warning.default, { bold: true }),
     rule(["extmark.agent"], theme.categorical[0][step], { bold: true }),
-    rule(["extmark.skill"], theme.categorical[1][step], { bold: true }),
     // V1 migration preserves its selected/inverse foreground in this action state.
     rule(["extmark.paste"], theme.text.action.primary.focused, {
       background: feedback.warning.default,

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

@@ -19,9 +19,8 @@ import { Locale } from "../../util/locale"
 import type { PromptInfo, PromptPartRef } from "../../prompt/history"
 import { useFrecency } from "../../prompt/frecency"
 import { Keymap } from "../../context/keymap"
-import { displayCharAt, mentionTriggerIndex, slashTriggerIndex } from "../../prompt/display"
+import { displayCharAt, mentionTriggerIndex } from "../../prompt/display"
 import type { FileSystemEntry } from "@opencode-ai/client"
-import { Skill } from "@opencode-ai/schema/skill"
 import { stringWidth } from "../../util/string-width"
 import { parseFileLineRange, stripFileLineRange } from "../../prompt/parse"
 import { moveSelection, revealSelectionOffset } from "../../ui/select-controller"
@@ -40,7 +39,6 @@ export type AutocompleteOption = {
   isDirectory?: boolean
   onSelect?: () => void
   path?: string
-  kind?: "skill"
 }
 
 export function Autocomplete(props: {
@@ -53,8 +51,6 @@ export function Autocomplete(props: {
   ref: (ref: AutocompleteRef) => void
   fileStyleId: number
   agentStyleId: number
-  skillStyleId: number
-  hasSkill: (id: string) => boolean
   promptPartTypeId: () => number
 }) {
   const editor = useEditorContext()
@@ -144,17 +140,14 @@ export function Autocomplete(props: {
     text: string,
     part:
       | { type: "file"; value: NonNullable<PromptInfo["files"]>[number]; path?: string }
-      | { type: "agent"; value: NonNullable<PromptInfo["agents"]>[number] }
-      | { type: "skill"; value: NonNullable<PromptInfo["skills"]>[number] },
+      | { type: "agent"; value: NonNullable<PromptInfo["agents"]>[number] },
   ) {
-    if (part.type === "skill" && props.hasSkill(part.value.id)) return
     const input = props.input()
     const currentCursorOffset = input.cursorOffset
 
     const charAfterCursor = displayCharAt(props.value, currentCursorOffset)
     const needsSpace = charAfterCursor !== " "
-    const prefix = part.type === "skill" ? "/" : "@"
-    const append = prefix + text + (needsSpace ? " " : "")
+    const append = "@" + text + (needsSpace ? " " : "")
 
     input.cursorOffset = store.index
     const startCursor = input.logicalCursor
@@ -164,12 +157,11 @@ export function Autocomplete(props: {
     input.deleteRange(startCursor.row, startCursor.col, endCursor.row, endCursor.col)
     input.insertText(append)
 
-    const virtualText = prefix + text
+    const virtualText = "@" + text
     const extmarkStart = store.index
     const extmarkEnd = extmarkStart + stringWidth(virtualText)
 
-    const styleId =
-      part.type === "file" ? props.fileStyleId : part.type === "skill" ? props.skillStyleId : props.agentStyleId
+    const styleId = part.type === "file" ? props.fileStyleId : props.agentStyleId
 
     const extmarkId = input.extmarks.create({
       start: extmarkStart,
@@ -203,20 +195,6 @@ export function Autocomplete(props: {
         return
       }
 
-      if (part.type === "skill") {
-        const skills = (draft.skills ??= [])
-        if (skills.some((skill) => skill.id === part.value.id)) return
-        if (part.value.mention) {
-          part.value.mention.start = extmarkStart
-          part.value.mention.end = extmarkEnd
-          part.value.mention.text = virtualText
-        }
-        const index = skills.length
-        skills.push(part.value)
-        props.setExtmark({ type: "skill", index }, extmarkId)
-        return
-      }
-
       const agents = (draft.agents ??= [])
       if (part.value.mention) {
         part.value.mention.start = extmarkStart
@@ -455,12 +433,7 @@ export function Autocomplete(props: {
       results.push({
         display: "/" + skill.id,
         description: skill.description,
-        kind: "skill",
-        onSelect: () =>
-          insertPart(skill.id, {
-            type: "skill",
-            value: { id: Skill.ID.make(skill.id), mention: { start: 0, end: 0, text: "" } },
-          }),
+        onSelect: () => insertSlash(skill.id),
       })
     }
 
@@ -490,11 +463,7 @@ export function Autocomplete(props: {
     // it shouldn't be additionally sorted by fuzzysort as it will loose the results
     const fileOptions: AutocompleteOption[] = store.visible === "@" ? fileSearch.options : []
     const nonFileOptions: AutocompleteOption[] =
-      store.visible === "@"
-        ? [...referenceAliasesValue, ...agentsValue, ...mcpResources()]
-        : store.index === 0
-          ? [...commandsValue]
-          : commandsValue.filter((item) => item.kind === "skill")
+      store.visible === "@" ? [...referenceAliasesValue, ...agentsValue, ...mcpResources()] : [...commandsValue]
 
     if (!searchValue) {
       return [...nonFileOptions, ...fileOptions]
@@ -551,7 +520,7 @@ export function Autocomplete(props: {
   function select() {
     const selected = options()[store.selected]
     if (!selected) return
-    hide(true)
+    hide()
     selected.onSelect?.()
   }
 
@@ -639,18 +608,14 @@ export function Autocomplete(props: {
     })
   }
 
-  function hide(removeToken = false) {
-    if (removeToken && store.visible === "/") {
-      const input = props.input()
-      const cursorOffset = input.cursorOffset
-      input.cursorOffset = store.index
-      const start = input.logicalCursor
-      input.cursorOffset = cursorOffset
-      const end = input.logicalCursor
-      input.deleteRange(start.row, start.col, end.row, end.col)
+  function hide() {
+    const text = props.input().plainText
+    if (store.visible === "/" && !text.endsWith(" ") && text.startsWith("/")) {
+      const cursor = props.input().logicalCursor
+      props.input().deleteRange(0, 0, cursor.row, cursor.col)
       // Sync the prompt store immediately since onContentChange is async
       props.setPrompt((draft) => {
-        draft.text = input.plainText
+        draft.text = props.input().plainText
       })
     }
     setStore("visible", false)
@@ -675,7 +640,9 @@ export function Autocomplete(props: {
             // Typed text before the trigger
             props.input().cursorOffset <= store.index ||
             // There is a space between the trigger and the cursor
-            props.input().getTextRange(store.index, props.input().cursorOffset).match(/\s/)
+            props.input().getTextRange(store.index, props.input().cursorOffset).match(/\s/) ||
+            // "/<command>" is not the sole content
+            (store.visible === "/" && value.match(/^\S+\s+\S+\s*$/))
           ) {
             hide()
           }
@@ -686,10 +653,10 @@ export function Autocomplete(props: {
         const offset = props.input().cursorOffset
         if (offset === 0) return
 
-        const slash = slashTriggerIndex(value, offset)
-        if (slash !== undefined) {
+        // Check for "/" at position 0 - reopen slash commands
+        if (value.startsWith("/") && !value.slice(0, offset).match(/\s/)) {
           show("/")
-          setStore("index", slash)
+          setStore("index", 0)
           return
         }
 

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

@@ -29,7 +29,6 @@ import { parseSlashHead } from "../../prompt/parse"
 import { stringWidth } from "../../util/string-width"
 import { createStore, produce, unwrap } from "solid-js/store"
 import { emptyPrompt, usePromptHistory, type PromptInfo, type PromptPartRef } from "../../prompt/history"
-import { Skill } from "@opencode-ai/schema/skill"
 import { computePromptTraits } from "../../prompt/traits"
 import { expandPastedTextPlaceholders, expandTrackedPastedText } from "../../prompt/part"
 import { usePromptStash } from "../../prompt/stash"
@@ -274,7 +273,6 @@ export function Prompt(props: PromptProps) {
   }
   const fileStyleId = syntax().getStyleId("extmark.file")!
   const agentStyleId = syntax().getStyleId("extmark.agent")!
-  const skillStyleId = syntax().getStyleId("extmark.skill")!
   const pasteStyleId = syntax().getStyleId("extmark.paste")!
   let promptPartTypeId = 0
   const event = useEvent()
@@ -495,29 +493,12 @@ export function Prompt(props: PromptProps) {
             <DialogSkill
               location={currentLocation.current}
               onSelect={(skill) => {
-                if (store.prompt.skills?.some((item) => item.id === skill)) return
-                const text = `/${skill}`
-                const start = input.cursorOffset
-                input.insertText(text + " ")
-                const extmarkId = input.extmarks.create({
-                  start,
-                  end: start + promptOffsetWidth(text),
-                  virtual: true,
-                  styleId: skillStyleId,
-                  typeId: promptPartTypeId,
+                input.setText(`/${skill} `)
+                setStore("prompt", {
+                  ...emptyPrompt(),
+                  text: `/${skill} `,
                 })
-                setStore(
-                  produce((draft) => {
-                    draft.prompt.text = input.plainText
-                    const skills = (draft.prompt.skills ??= [])
-                    const index = skills.length
-                    skills.push({
-                      id: Skill.ID.make(skill),
-                      mention: { start, end: start + promptOffsetWidth(text), text },
-                    })
-                    draft.extmarkToPart.set(extmarkId, { type: "skill", index })
-                  }),
-                )
+                input.gotoBufferEnd()
               }}
             />
           ))
@@ -658,11 +639,6 @@ export function Prompt(props: PromptProps) {
         ref: { type: "agent" as const, index },
         styleId: agentStyleId,
       })),
-      ...(prompt.skills ?? []).map((part, index) => ({
-        mention: part.mention,
-        ref: { type: "skill" as const, index },
-        styleId: skillStyleId,
-      })),
       ...prompt.pasted.map((part, index) => ({
         mention: part.source,
         ref: { type: "pasted" as const, index },
@@ -695,7 +671,6 @@ export function Prompt(props: PromptProps) {
         const newMap = new Map<number, PromptPartRef>()
         const files: NonNullable<PromptInfo["files"]> = []
         const agents: NonNullable<PromptInfo["agents"]> = []
-        const skills: NonNullable<PromptInfo["skills"]> = []
         const pasted: PromptInfo["pasted"] = []
 
         for (const extmark of allExtmarks) {
@@ -721,16 +696,6 @@ export function Prompt(props: PromptProps) {
             newMap.set(extmark.id, { type: "agent", index })
             continue
           }
-          if (ref.type === "skill") {
-            const part = draft.prompt.skills?.[ref.index]
-            if (!part?.mention) continue
-            part.mention.start = extmark.start
-            part.mention.end = extmark.end
-            const index = skills.length
-            skills.push(part)
-            newMap.set(extmark.id, { type: "skill", index })
-            continue
-          }
           const part = draft.prompt.pasted[ref.index]
           if (!part) continue
           part.source.start = extmark.start
@@ -743,7 +708,6 @@ export function Prompt(props: PromptProps) {
         draft.extmarkToPart = newMap
         draft.prompt.files = files
         draft.prompt.agents = agents
-        draft.prompt.skills = skills
         draft.prompt.pasted = pasted
       }),
     )
@@ -1019,7 +983,6 @@ export function Prompt(props: PromptProps) {
     )
     const slashHead = parseSlashHead(inputText, /\s/)
     const isSkill =
-      !(store.prompt.skills?.length ?? 0) &&
       slashHead !== undefined &&
       (data.location.skill.list(currentLocation.ref) ?? []).some(
         (skill) => skill.slash === true && skill.id === slashHead.name,
@@ -1117,7 +1080,6 @@ export function Prompt(props: PromptProps) {
           model,
           files: store.prompt.files,
           agents: store.prompt.agents,
-          skills: store.prompt.skills?.length ? store.prompt.skills : undefined,
           delivery,
         })
         .catch((error) => {
@@ -1184,7 +1146,6 @@ export function Prompt(props: PromptProps) {
           text: inputText,
           files: store.prompt.files,
           agents: store.prompt.agents,
-          skills: store.prompt.skills?.length ? store.prompt.skills : undefined,
           delivery,
         })
         .then(
@@ -1724,8 +1685,6 @@ export function Prompt(props: PromptProps) {
         value={store.prompt.text}
         fileStyleId={fileStyleId}
         agentStyleId={agentStyleId}
-        skillStyleId={skillStyleId}
-        hasSkill={(id) => store.prompt.skills?.some((skill) => skill.id === id) ?? false}
         promptPartTypeId={() => promptPartTypeId}
       />
     </>

packages/tui/src/mini/footer.prompt.tsx

@@ -21,7 +21,6 @@ import {
   isExitCommand,
   isCompactCommand,
   mentionTriggerIndex,
-  slashTriggerIndex,
   isNewCommand,
   movePromptHistory,
   promptCopy,
@@ -51,7 +50,7 @@ export const TEXTAREA_MIN_ROWS = 1
 const TEXTAREA_MAX_ROWS = 6
 export const PROMPT_MAX_ROWS = TEXTAREA_MAX_ROWS + AUTOCOMPLETE_ROWS - 1 + AUTOCOMPLETE_BOTTOM_ROWS
 
-type Mention = Extract<RunPromptPart, { type: "file" | "agent" | "skill" }>
+type Mention = Extract<RunPromptPart, { type: "file" | "agent" }>
 
 type Auto = RunFooterMenuItem & {
   kind: "mention"
@@ -66,12 +65,7 @@ type SlashOption = RunFooterMenuItem & {
   action?: "skill-menu" | "editor" | "settings"
 }
 
-type SkillOption = RunFooterMenuItem & {
-  kind: "skill"
-  id: string
-}
-
-type PromptOption = Auto | SlashOption | SkillOption
+type PromptOption = Auto | SlashOption
 
 type MenuMode = false | "mention" | "slash"
 
@@ -130,9 +124,12 @@ function emptyPrompt(shell: boolean): RunPrompt {
 }
 
 function slashQuery(text: string, cursor: number) {
-  const at = slashTriggerIndex(text, cursor)
-  if (at === undefined) return
-  return { at, value: displaySlice(text, at + 1, cursor) }
+  const head = parseSlashHead(text.slice(0, cursor))
+  if (!head || head.end !== cursor) {
+    return
+  }
+
+  return head.name
 }
 
 function parseSlashCommand(text: string, commands: RunCommand[] | undefined) {
@@ -385,18 +382,10 @@ export function createPromptState(input: PromptInput): PromptState {
   )
   const mentionOptions = createMemo(() => [...agents(), ...files(), ...references()])
   const skillCommands = createMemo(() => (input.commands() ?? []).filter((item) => item.source === "skill"))
-  const skillOptions = createMemo<SkillOption[]>(() =>
-    skillCommands().map((item) => ({
-      kind: "skill",
-      id: item.name,
-      display: `/${item.name}`,
-      description: item.description,
-    })),
-  )
   const hasSkillsCommand = createMemo(() =>
     (input.commands() ?? []).some((item) => item.source !== "skill" && item.name === "skills"),
   )
-  const slashOptions = createMemo<Array<SlashOption | SkillOption>>(() => {
+  const slashOptions = createMemo<SlashOption[]>(() => {
     const builtins = [
       {
         kind: "slash",
@@ -428,7 +417,6 @@ export function createPromptState(input: PromptInput): PromptState {
     }
 
     return [
-      ...skillOptions(),
       ...(showSkillMenu
         ? [
             {
@@ -455,7 +443,7 @@ export function createPromptState(input: PromptInput): PromptState {
     ].sort((a, b) => a.display.localeCompare(b.display))
   })
   const options = createMemo<PromptOption[]>(() => {
-    const mixed: PromptOption[] = mode() === "slash" ? (at() === 0 ? slashOptions() : skillOptions()) : mentionOptions()
+    const mixed: PromptOption[] = mode() === "slash" ? slashOptions() : mentionOptions()
     if (!query()) {
       return mixed
     }
@@ -471,11 +459,7 @@ export function createPromptState(input: PromptInput): PromptState {
 
     return fuzzysort
       .go(next, mixed, {
-        keys: [
-          (item) => (item.kind === "mention" ? item.value : item.kind === "skill" ? item.id : item.name).trimEnd(),
-          "display",
-          "description",
-        ],
+        keys: [(item) => (item.kind === "mention" ? item.value : item.name).trimEnd(), "display", "description"],
       })
       .map((item) => item.obj)
   })
@@ -532,15 +516,13 @@ export function createPromptState(input: PromptInput): PromptState {
       const prev =
         part.type === "agent"
           ? (part.source?.value ?? "@" + part.name)
-          : part.type === "skill"
-            ? (part.source?.value ?? "/" + part.id)
-            : (part.source?.text.value ?? "@" + (part.filename ?? ""))
+          : (part.source?.text.value ?? "@" + (part.filename ?? ""))
       if (text !== prev) {
         continue
       }
 
       const copy = structuredClone(part)
-      if (copy.type === "agent" || copy.type === "skill") {
+      if (copy.type === "agent") {
         copy.source = {
           start: item.start,
           end: item.end,
@@ -576,7 +558,7 @@ export function createPromptState(input: PromptInput): PromptState {
   const restoreParts = (value: RunPromptPart[]) => {
     clearParts()
     parts = value
-      .filter((item): item is Mention => item.type === "file" || item.type === "agent" || item.type === "skill")
+      .filter((item): item is Mention => item.type === "file" || item.type === "agent")
       .map((item) => structuredClone(item))
     if (!area || area.isDestroyed || type === 0) {
       return
@@ -584,8 +566,8 @@ export function createPromptState(input: PromptInput): PromptState {
 
     const box = area
     parts.forEach((item, idx) => {
-      const start = item.type === "file" ? item.source?.text.start : item.source?.start
-      const end = item.type === "file" ? item.source?.text.end : item.source?.end
+      const start = item.type === "agent" ? item.source?.start : item.source?.text.start
+      const end = item.type === "agent" ? item.source?.end : item.source?.text.end
       if (start === undefined || end === undefined) {
         return
       }
@@ -645,16 +627,16 @@ export function createPromptState(input: PromptInput): PromptState {
         return
       }
 
-      setAt(slash.at)
-      setQuery(slash.value)
+      setAt(0)
+      setQuery(slash)
       return
     }
 
     if (slash !== undefined) {
-      setAt(slash.at)
+      setAt(0)
       menu.reset()
       setMode("slash")
-      setQuery(slash.value)
+      setQuery(slash)
       return
     }
 
@@ -800,7 +782,7 @@ export function createPromptState(input: PromptInput): PromptState {
     }
 
     const cursor = area.cursorOffset
-    const startOffset = at()
+    const startOffset = mode() === "slash" ? 0 : at()
     area.cursorOffset = startOffset
     const start = area.logicalCursor
     area.cursorOffset = cursor
@@ -846,39 +828,6 @@ export function createPromptState(input: PromptInput): PromptState {
       return
     }
 
-    if (next.kind === "skill") {
-      if (parts.some((part) => part.type === "skill" && part.id === next.id)) {
-        cancelAutocomplete()
-        return
-      }
-      const cursor = area.cursorOffset
-      const tail = displayCharAt(area.plainText, cursor)
-      const append = `/${next.id}${tail === " " ? "" : " "}`
-      area.cursorOffset = at()
-      const start = area.logicalCursor
-      area.cursorOffset = cursor
-      const end = area.logicalCursor
-      area.deleteRange(start.row, start.col, end.row, end.col)
-      area.insertText(append)
-
-      const text = `/${next.id}`
-      const startOffset = at()
-      const endOffset = startOffset + stringWidth(text)
-      const part: Extract<RunPromptPart, { type: "skill" }> = {
-        type: "skill",
-        id: next.id,
-        source: { start: startOffset, end: endOffset, value: text },
-      }
-      const id = area.extmarks.create({ start: startOffset, end: endOffset, virtual: true, typeId: type })
-      marks.set(id, parts.length)
-      parts.push(part)
-      hide()
-      syncDraft()
-      scheduleRows()
-      area.focus()
-      return
-    }
-
     if (next.kind === "slash") {
       if (next.action === "editor") {
         void openEditor({
@@ -1244,7 +1193,7 @@ export function createPromptState(input: PromptInput): PromptState {
     }
 
     const parsed =
-      command || next.parts.some((part) => part.type === "skill") || next.mode === "shell" || isNewCommand(next.text)
+      command || next.mode === "shell" || isNewCommand(next.text)
         ? undefined
         : parseSlashCommand(next.text, input.commands())
     if (parsed?.type === "pending") {

packages/tui/src/mini/prompt.editor.ts

@@ -2,7 +2,7 @@ import type { RunPromptPart } from "./types"
 import { realignPromptMentions } from "../prompt/mention"
 import { parseSlashHead } from "../prompt/parse"
 
-type Mention = Extract<RunPromptPart, { type: "file" | "agent" | "skill" }>
+type Mention = Extract<RunPromptPart, { type: "file" | "agent" }>
 
 export function resolveEditorSlashValue(text: string) {
   const head = parseSlashHead(text)
@@ -17,13 +17,13 @@ export function realignEditorPromptParts(content: string, parts: RunPromptPart[]
   const matches = realignPromptMentions(
     content,
     parts.map((part) => {
-      if (part.type !== "file" && part.type !== "agent" && part.type !== "skill") return
+      if (part.type !== "file" && part.type !== "agent") return
       return promptPartMention(part)
     }),
   )
 
   return parts.flatMap((part, index) => {
-    if (part.type !== "file" && part.type !== "agent" && part.type !== "skill") return [part]
+    if (part.type !== "file" && part.type !== "agent") return [part]
     const mention = promptPartMention(part)
     if (!mention?.text) return [part]
     const match = matches[index]
@@ -32,13 +32,13 @@ export function realignEditorPromptParts(content: string, parts: RunPromptPart[]
 }
 
 function promptPartMention(part: Mention) {
-  const source = part.type === "file" ? part.source?.text : part.source
+  const source = part.type === "agent" ? part.source : part.source?.text
   if (!source) return
   return { start: source.start, end: source.end, text: source.value }
 }
 
 function updatePromptPart(part: Mention, start: number, end: number, text: string): Mention {
-  if (part.type === "agent" || part.type === "skill") {
+  if (part.type === "agent") {
     return {
       ...part,
       source: {

packages/tui/src/mini/prompt.shared.ts

@@ -7,7 +7,7 @@
 // the current browse position. When the user arrows up at cursor offset 0,
 // the current draft is saved and history begins. Arrowing past the end
 // restores the draft.
-export { displayCharAt, displaySlice, mentionTriggerIndex, slashTriggerIndex } from "../prompt/display"
+export { displayCharAt, displaySlice, mentionTriggerIndex } from "../prompt/display"
 import { stringWidth } from "../util/string-width"
 import type { RunPrompt } from "./types"
 

packages/tui/src/mini/stream-v2.transport.ts

@@ -288,21 +288,6 @@ function promptAgents(next: SessionTurnInput) {
   )
 }
 
-function promptSkills(next: SessionTurnInput) {
-  return next.prompt.parts.flatMap((part) =>
-    part.type === "skill"
-      ? [
-          {
-            id: part.id,
-            mention: part.source
-              ? { start: part.source.start, end: part.source.end, text: part.source.value }
-              : undefined,
-          },
-        ]
-      : [],
-  )
-}
-
 function streamPartKey(messageID: string, partID: string) {
   return `${messageID}\u0000${partID}`
 }
@@ -373,12 +358,12 @@ const catalogEvents = new Set([
 // briefly so the output commit renders inside it.
 const SHELL_OUTPUT_GRACE_MS = 1500
 
-function skillCommit(messageID: string, name: string, skillID = messageID): StreamCommit {
+function skillCommit(messageID: string, name: string): StreamCommit {
   return {
     kind: "system",
     source: "system",
     messageID,
-    partID: `skill:${skillID}`,
+    partID: `skill:${messageID}`,
     text: `→ Skill "${name}"`,
     phase: "start",
   }
@@ -652,10 +637,7 @@ export async function createSessionTransport(input: StreamInput): Promise<Sessio
       state.messageIDs.add(message.id)
       if (!render) return
       if (reuseVisibleWait && waiting) return
-      write([
-        ...(message.skills ?? []).map((skill) => skillCommit(message.id, skill.name, skill.id)),
-        { kind: "user", source: "system", text: message.text, phase: "start", messageID: message.id },
-      ])
+      write([{ kind: "user", source: "system", text: message.text, phase: "start", messageID: message.id }])
       return
     }
     if (message.type === "skill") {
@@ -1636,7 +1618,6 @@ export async function createSessionTransport(input: StreamInput): Promise<Sessio
     const command = next.prompt.command
     const attachments = await prepareAttachments(next, command ? "command" : "prompt", input.readTextFile)
     const agents = promptAgents(next)
-    const skills = promptSkills(next)
     if (!command) {
       input.trace?.write("send.prompt", { sessionID: input.sessionID, messageID, delivery })
       return client.session.prompt(
@@ -1646,7 +1627,6 @@ export async function createSessionTransport(input: StreamInput): Promise<Sessio
           text: [next.prompt.text, ...attachments.text].join("\n\n"),
           files: attachments.files.length ? attachments.files : undefined,
           agents: agents.length ? agents : undefined,
-          skills: skills.length ? skills : undefined,
           delivery,
         },
         { signal: next.signal },
@@ -1666,7 +1646,6 @@ export async function createSessionTransport(input: StreamInput): Promise<Sessio
         model: selected,
         files: attachments.files.length ? attachments.files : undefined,
         agents: agents.length ? agents : undefined,
-        skills: skills.length ? skills : undefined,
         delivery,
       },
       { signal: next.signal },

packages/tui/src/mini/types.ts

@@ -47,7 +47,6 @@ export type RunPromptPart =
       }
     }
   | { type: "agent"; name: string; source?: { start: number; end: number; value: string } }
-  | { type: "skill"; id: string; source?: { start: number; end: number; value: string } }
 
 export type RunCommand = {
   name: string

packages/tui/src/prompt/codec.ts

@@ -1,14 +1,9 @@
 import type { Prompt, PromptInput } from "@opencode-ai/schema"
-import { Skill } from "@opencode-ai/schema/skill"
 import type { Types } from "effect"
 
 export type EditablePromptInput = Types.DeepMutable<PromptInput.Prompt>
 
-type ProjectedPrompt = Pick<Prompt, "text" | "files" | "agents"> & {
-  readonly skills?: ReadonlyArray<{ readonly id: string; readonly mention?: PromptInput.SkillAttachment["mention"] }>
-}
-
-export function projectedPromptInput(input: ProjectedPrompt): EditablePromptInput {
+export function projectedPromptInput(input: Pick<Prompt, "text" | "files" | "agents">): EditablePromptInput {
   return {
     text: input.text,
     files: input.files?.map((file) => ({
@@ -21,9 +16,5 @@ export function projectedPromptInput(input: ProjectedPrompt): EditablePromptInpu
       name: agent.name,
       mention: agent.mention ? { ...agent.mention } : undefined,
     })),
-    skills: input.skills?.map((skill) => ({
-      id: Skill.ID.make(skill.id),
-      mention: skill.mention ? { ...skill.mention } : undefined,
-    })),
   }
 }

packages/tui/src/prompt/display.ts

@@ -48,14 +48,3 @@ export function mentionTriggerIndex(value: string, offset = promptOffsetWidth(va
     return promptOffsetWidth(text.slice(0, index))
   }
 }
-
-export function slashTriggerIndex(value: string, offset = promptOffsetWidth(value)) {
-  const text = displaySlice(value, 0, offset)
-  for (let index = text.lastIndexOf("/"); index >= 0; index = text.lastIndexOf("/", index - 1)) {
-    const before = index === 0 ? undefined : text[index - 1]
-    const query = text.slice(index)
-    if (before !== undefined && !/\s/.test(before)) continue
-    if (/\s/.test(query) || query.slice(1).includes("/")) return
-    return promptOffsetWidth(text.slice(0, index))
-  }
-}

packages/tui/src/prompt/history.tsx

@@ -1,7 +1,7 @@
 import path from "path"
 import { onMount } from "solid-js"
 import { createStore, produce, unwrap } from "solid-js/store"
-import type { PromptInput } from "@opencode-ai/schema"
+import type { SessionPromptInput } from "@opencode-ai/client"
 import type { Types } from "effect"
 import { createSimpleContext } from "../context/helper"
 import { useTuiPaths } from "../context/runtime"
@@ -16,17 +16,17 @@ export type PastedText = {
   }
 }
 
-export type PromptInfo = Types.DeepMutable<Pick<PromptInput.Prompt, "text" | "files" | "agents" | "skills">> & {
+export type PromptInfo = Types.DeepMutable<Pick<SessionPromptInput, "text" | "files" | "agents">> & {
   pasted: PastedText[]
   mode?: "normal" | "shell"
 }
 
 export type PromptPartRef = {
-  type: "file" | "agent" | "skill" | "pasted"
+  type: "file" | "agent" | "pasted"
   index: number
 }
 
-export const emptyPrompt = (): PromptInfo => ({ text: "", files: [], agents: [], skills: [], pasted: [] })
+export const emptyPrompt = (): PromptInfo => ({ text: "", files: [], agents: [], pasted: [] })
 
 export const MAX_HISTORY_ENTRIES = 50
 

packages/tui/src/prompt/mention.ts

@@ -54,11 +54,9 @@ export function realignPromptMentions(
 export function realignPromptInputMentions(content: string, input: PromptInput.Prompt): EditablePromptInput {
   const files = input.files ?? []
   const agents = input.agents ?? []
-  const skills = input.skills ?? []
   const mentions = realignPromptMentions(content, [
     ...files.map((file) => file.mention),
     ...agents.map((agent) => agent.mention),
-    ...skills.map((skill) => skill.mention),
   ])
   const align = <T extends { mention?: PromptMention }>(items: readonly T[] | undefined, offset = 0) =>
     items?.flatMap((item, index) => {
@@ -71,7 +69,6 @@ export function realignPromptInputMentions(content: string, input: PromptInput.P
     text: content,
     files: align(input.files),
     agents: align(input.agents, files.length),
-    skills: align(input.skills, files.length + agents.length),
   }
 }
 
@@ -94,7 +91,6 @@ export function expandPromptInputPastedText(
     text: expandTrackedPastedText(input.text, ranges),
     files: input.files?.map((file) => ({ ...file, mention: shift(file.mention) })),
     agents: input.agents?.map((agent) => ({ ...agent, mention: shift(agent.mention) })),
-    skills: input.skills?.map((skill) => ({ ...skill, mention: shift(skill.mention) })),
   }
 }
 

packages/tui/src/routes/session/index.tsx

@@ -1911,7 +1911,6 @@ function UserMessage(props: { message: SessionMessageUser }) {
   const data = useData()
   const local = useLocal()
   const files = createMemo(() => props.message.files ?? [])
-  const skills = createMemo(() => props.message.skills ?? [])
   const themes = useThemes()
   const theme = useTheme("elevated")
   const mode = themes.mode
@@ -1927,7 +1926,7 @@ function UserMessage(props: { message: SessionMessageUser }) {
   }
 
   return (
-    <Show when={props.message.text.trim() || files().length || skills().length}>
+    <Show when={props.message.text.trim() || files().length}>
       <box
         border={["left"]}
         borderColor={delivery() ? theme.border.default : color()}
@@ -1972,28 +1971,6 @@ function UserMessage(props: { message: SessionMessageUser }) {
           flexShrink={0}
         >
           <text fg={theme.text.default}>{props.message.text}</text>
-          <Show when={skills().length}>
-            <box flexDirection="row" paddingTop={1} gap={1} flexWrap="wrap">
-              <For each={skills()}>
-                {(skill) => (
-                  <text fg={theme.text.default}>
-                    <span
-                      style={{
-                        bg: theme.hue.accent[mode() === "light" ? 700 : 200],
-                        fg: theme.background.default,
-                        bold: true,
-                      }}
-                    >
-                      {" skill "}
-                    </span>
-                    <span style={{ bg: theme.raise(theme.background.default), fg: theme.text.subdued }}>
-                      {` ${skill.name} `}
-                    </span>
-                  </text>
-                )}
-              </For>
-            </box>
-          </Show>
           <Show when={files().length}>
             <box flexDirection="row" paddingTop={1} gap={1} flexWrap="wrap">
               <For each={files()}>

packages/tui/test/mini/footer.view.test.tsx

@@ -1262,44 +1262,6 @@ test("direct footer tags skill slash submissions with their catalog source", asy
   }
 })
 
-test("direct footer submits a selected leading skill as a prompt attachment", async () => {
-  const submits: RunPrompt[] = []
-  const app = await renderFooter({
-    commands: [command({ name: "formatter", description: "Apply formatter fixes", source: "skill" })],
-    onSubmit(prompt) {
-      submits.push(prompt)
-      return true
-    },
-  })
-
-  try {
-    await app.renderOnce()
-    "/forma".split("").forEach((key) => app.mockInput.pressKey(key))
-    await app.renderOnce()
-    app.mockInput.pressEnter()
-    await app.renderOnce()
-    "src".split("").forEach((key) => app.mockInput.pressKey(key))
-    app.mockInput.pressEnter()
-    await app.renderOnce()
-
-    expect(submits).toEqual([
-      {
-        text: "/formatter src",
-        parts: [
-          {
-            type: "skill",
-            id: "formatter",
-            source: { start: 0, end: 10, value: "/formatter" },
-          },
-        ],
-        delivery: "steer",
-      },
-    ])
-  } finally {
-    app.cleanup()
-  }
-})
-
 // OpenTUI currently segfaults Bun while tearing down this composer-to-skill-panel transition.
 // Re-enable after the upstream renderer teardown fix lands.
 test.skip("direct footer skill picker inserts an editable bound skill command", async () => {

packages/tui/test/mini/stream-v2.transport.test.ts

@@ -2749,7 +2749,7 @@ describe("V2 mini transport", () => {
       variant: undefined,
       prompt: {
         messageID: "msg_cmd",
-        text: "/deploy prod /api-design",
+        text: "/deploy prod",
         parts: [
           {
             type: "file",
@@ -2757,11 +2757,6 @@ describe("V2 mini transport", () => {
             filename: "mentioned.txt",
             source: { type: "file", text: { start: 8, end: 12, value: "prod" } },
           },
-          {
-            type: "skill",
-            id: "api-design",
-            source: { start: 13, end: 24, value: "/api-design" },
-          },
         ],
         command: { name: "deploy", arguments: "prod" },
       },
@@ -2784,7 +2779,6 @@ describe("V2 mini transport", () => {
           mention: { start: 8, end: 12, text: "prod" },
         },
       ],
-      skills: [{ id: "api-design", mention: { start: 13, end: 24, text: "/api-design" } }],
       delivery: "steer",
     })
     // Selection rides the command payload; no separate client-side switch.
@@ -2857,75 +2851,6 @@ describe("V2 mini transport", () => {
     await transport.close()
   })
 
-  test("sends inline skill attachments with a normal prompt", async () => {
-    const events = feed()
-    events.push(connected())
-    const client = sdk({ streams: [events] })
-    const ui = footer()
-    const transport = await createSessionTransport({
-      sdk: client,
-      sessionID: "ses_1",
-      thinking: false,
-      footer: ui.api,
-    })
-    let request: Parameters<OpenCodeClient["session"]["prompt"]>[0] | undefined
-    spyOn(client.session, "prompt").mockImplementation((input) => {
-      request = input
-      queueMicrotask(() => {
-        events.push({
-          id: "evt_prompted",
-          created: 0,
-          type: "session.input.promoted",
-          durable: durable("ses_1"),
-          data: { sessionID: "ses_1", inputID: "msg_skill_attachment" },
-        })
-        events.push({
-          id: "evt_settled",
-          created: 0,
-          type: "session.execution.succeeded",
-          durable: durable("ses_1"),
-          data: { sessionID: "ses_1" },
-        })
-      })
-      return ok({
-        id: input.id ?? "msg_skill_attachment",
-        sessionID: "ses_1",
-        type: "user" as const,
-        data: { text: input.text },
-        delivery: "steer" as const,
-        timeCreated: 2,
-      })
-    })
-
-    await transport.runPromptTurn({
-      agent: undefined,
-      model: undefined,
-      variant: undefined,
-      prompt: {
-        messageID: "msg_skill_attachment",
-        text: "Review this /api-design",
-        parts: [
-          {
-            type: "skill",
-            id: "api-design",
-            source: { start: 12, end: 23, value: "/api-design" },
-          },
-        ],
-      },
-      files: [],
-      includeFiles: false,
-    })
-
-    expect(request).toMatchObject({
-      sessionID: "ses_1",
-      id: "msg_skill_attachment",
-      text: "Review this /api-design",
-      skills: [{ id: "api-design", mention: { start: 12, end: 23, text: "/api-design" } }],
-      delivery: "steer",
-    })
-    await transport.close()
-  })
-
   test("refreshes catalogs on connection and location-scoped invalidations", async () => {
     const events = feed()
     events.push(connected())

packages/tui/test/prompt/display.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, test } from "bun:test"
-import { displayCharAt, displaySlice, mentionTriggerIndex, slashTriggerIndex } from "../../src/prompt/display"
+import { displayCharAt, displaySlice, mentionTriggerIndex } from "../../src/prompt/display"
 
 describe("prompt display", () => {
   test("uses display-width offsets for mentions", () => {
@@ -30,14 +30,4 @@ describe("prompt display", () => {
     expect(mentionTriggerIndex("foo@bar.com")).toBeUndefined()
     expect(mentionTriggerIndex("中文 @src file")).toBeUndefined()
   })
-
-  test("finds slash attachments at token boundaries", () => {
-    expect(slashTriggerIndex("/")).toBe(0)
-    expect(slashTriggerIndex("Review this /api-design")).toBe(12)
-    expect(slashTriggerIndex("中文 /api-design")).toBe(5)
-    expect(slashTriggerIndex("Review /api design")).toBeUndefined()
-    expect(slashTriggerIndex("Review /tmp/file.ts")).toBeUndefined()
-    expect(slashTriggerIndex("https://opencode.ai/docs")).toBeUndefined()
-    expect(slashTriggerIndex("src/prompt/index.ts")).toBeUndefined()
-  })
 })