diff --git a/packages/core/src/session.ts b/packages/core/src/session.ts
index cf167b4d7..cdd4a4a7c 100644
--- a/packages/core/src/session.ts
+++ b/packages/core/src/session.ts
@@ -77,19 +77,12 @@ export class NotFoundError extends Schema.TaggedErrorClass<NotFoundError>()("Ses
   sessionID: SessionSchema.ID,
 }) {}
 
-export class OperationUnavailableError extends Schema.TaggedErrorClass<OperationUnavailableError>()(
-  "Session.OperationUnavailableError",
-  {
-    operation: Schema.Literals(["prompt", "compact", "wait"]),
-  },
-) {}
-
 export class MessageDecodeError extends Schema.TaggedErrorClass<MessageDecodeError>()("Session.MessageDecodeError", {
   sessionID: SessionSchema.ID,
   messageID: SessionMessage.ID,
 }) {}
 
-export type Error = NotFoundError | OperationUnavailableError | MessageDecodeError
+export type Error = NotFoundError | MessageDecodeError
 
 export interface Interface {
   readonly list: (input?: ListInput) => Effect.Effect<SessionSchema.Info[]>
@@ -233,96 +226,24 @@ export const layer = Layer.effect(
         )
         return (direction === "previous" ? rows.toReversed() : rows).map((row) => fromRow(row))
       }),
-      messages: Effect.fn("V2Session.messages")(function* (input) {
-        yield* result.get(input.sessionID)
-        const direction = input.cursor?.direction ?? "next"
-        const requestedOrder = input.order ?? "desc"
-        const order = direction === "previous" ? (requestedOrder === "asc" ? "desc" : "asc") : requestedOrder
-        const boundary = input.cursor
-          ? order === "asc"
-            ? or(
-                gt(SessionMessageTable.time_created, input.cursor.time),
-                and(
-                  eq(SessionMessageTable.time_created, input.cursor.time),
-                  gt(SessionMessageTable.id, input.cursor.id),
-                ),
-              )
-            : or(
-                lt(SessionMessageTable.time_created, input.cursor.time),
-                and(
-                  eq(SessionMessageTable.time_created, input.cursor.time),
-                  lt(SessionMessageTable.id, input.cursor.id),
-                ),
-              )
-          : undefined
-        const where = boundary
-          ? and(eq(SessionMessageTable.session_id, input.sessionID), boundary)
-          : eq(SessionMessageTable.session_id, input.sessionID)
-        const query = db
-          .select()
-          .from(SessionMessageTable)
-          .where(where)
-          .orderBy(
-            order === "asc" ? asc(SessionMessageTable.time_created) : desc(SessionMessageTable.time_created),
-            order === "asc" ? asc(SessionMessageTable.id) : desc(SessionMessageTable.id),
-          )
-        const rows = yield* (input.limit === undefined ? query.all() : query.limit(input.limit).all()).pipe(
-          Effect.orDie,
-        )
-        return yield* Effect.forEach(direction === "previous" ? rows.toReversed() : rows, (row) => decode(row))
+      messages: Effect.fn("V2Session.messages")(function* () {
+        return yield* Effect.die(new Error("Session.messages is not implemented"))
       }),
-      context: Effect.fn("V2Session.context")(function* (sessionID) {
-        yield* result.get(sessionID)
-        const compaction = yield* db
-          .select()
-          .from(SessionMessageTable)
-          .where(and(eq(SessionMessageTable.session_id, sessionID), eq(SessionMessageTable.type, "compaction")))
-          .orderBy(desc(SessionMessageTable.time_created), desc(SessionMessageTable.id))
-          .limit(1)
-          .get()
-          .pipe(Effect.orDie)
-        const rows = yield* db
-          .select()
-          .from(SessionMessageTable)
-          .where(
-            and(
-              eq(SessionMessageTable.session_id, sessionID),
-              compaction
-                ? or(
-                    gt(SessionMessageTable.time_created, compaction.time_created),
-                    and(
-                      eq(SessionMessageTable.time_created, compaction.time_created),
-                      gte(SessionMessageTable.id, compaction.id),
-                    ),
-                  )
-                : undefined,
-            ),
-          )
-          .orderBy(asc(SessionMessageTable.time_created), asc(SessionMessageTable.id))
-          .all()
-          .pipe(Effect.orDie)
-        return yield* Effect.forEach(rows, (row) => decode(row))
+      context: Effect.fn("V2Session.context")(function* () {
+        return yield* Effect.die(new Error("Session.context is not implemented"))
       }),
-      prompt: Effect.fn("V2Session.prompt")(function* (input) {
-        yield* result.get(input.sessionID)
-        return yield* new OperationUnavailableError({ operation: "prompt" })
+      prompt: Effect.fn("V2Session.prompt")(function* () {
+        return yield* Effect.die(new Error("Session.prompt is not implemented"))
       }),
       shell: Effect.fn("V2Session.shell")(function* () {}),
       skill: Effect.fn("V2Session.skill")(function* () {}),
       switchAgent: Effect.fn("V2Session.switchAgent")(function* () {}),
       switchModel: Effect.fn("V2Session.switchModel")(function* () {}),
-      subagent: Effect.fn("V2Session.subagent")(function* (input) {
-        yield* result.get(input.parentID)
-        return yield* new OperationUnavailableError({ operation: "prompt" })
+      compact: Effect.fn("V2Session.compact")(function* () {
+        return yield* Effect.die(new Error("Session.compact is not implemented"))
       }),
-      compact: Effect.fn("V2Session.compact")(function* (input) {
-        const sessionID = typeof input === "string" ? input : input.sessionID
-        yield* result.get(sessionID)
-        return yield* new OperationUnavailableError({ operation: "compact" })
-      }),
-      wait: Effect.fn("V2Session.wait")(function* (sessionID) {
-        yield* result.get(sessionID)
-        return yield* new OperationUnavailableError({ operation: "wait" })
+      wait: Effect.fn("V2Session.wait")(function* () {
+        return yield* Effect.die(new Error("Session.wait is not implemented"))
       }),
       resume: Effect.fn("V2Session.resume")(function* () {}),
       move: Effect.fn("V2Session.move")(function* () {}),