From 514e2ed0ae5d3339789b54d4277d36b48533ba80 Mon Sep 17 00:00:00 2001
From: filipeforattini <filipeforattini1@gmail.com>
Date: Fri, 21 Aug 2026 12:01:38 -0300
Subject: [PATCH] feat(opencode): V2 text.complete alongside V1 trigger

Adds `SessionEvent.Text.Complete` (live waterfall event, type `session.next.text.complete`) carrying `{ sessionID, messageID, partID, text }` and wires `EventV2Bridge.waterfall` into the text-complete dispatch next to the existing V1 `plugin.trigger('experimental.text.complete', ...)`.

The waterfall currently has a single listener that delegates to the V1 trigger so existing plugins keep working. Listeners return `{ text }` to transform the final text; throwing short-circuits the text part. Same shim pattern as #70 #72 #75 #76 #77 #78 #79.
---
 packages/opencode/src/session/processor.ts | 14 ++++++++++++--
 packages/schema/src/session-event.ts       | 18 ++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/packages/opencode/src/session/processor.ts b/packages/opencode/src/session/processor.ts
index f5a8b74d76e6..3d1df77c0e9c 100644
--- a/packages/opencode/src/session/processor.ts
+++ b/packages/opencode/src/session/processor.ts
@@ -23,6 +23,7 @@ import { Question } from "@/question"
 import { errorMessage } from "@/util/error"
 import { isRecord } from "@/util/record"
 import { EventV2Bridge } from "@/event-v2-bridge"
+import { SessionEvent } from "@opencode-ai/core/session/event"
 import { Database } from "@opencode-ai/core/database/database"
 import { Usage, type LLMEvent } from "@opencode-ai/llm"
 
@@ -514,7 +515,7 @@ const layer = Layer.effect(
             if (!ctx.currentText) return
             // oxlint-disable-next-line no-self-assign -- reactivity trigger
             ctx.currentText.text = ctx.currentText.text
-            ctx.currentText.text = (yield* plugin.trigger(
+            const textCompleteV1 = yield* plugin.trigger(
               "experimental.text.complete",
               {
                 sessionID: ctx.sessionID,
@@ -522,7 +523,16 @@ const layer = Layer.effect(
                 partID: ctx.currentText.id,
               },
               { text: ctx.currentText.text },
-            )).text
+            )
+            const textCompleteV2 = yield* events.waterfall(SessionEvent.Text.Complete, [
+              (_e, next) =>
+                Effect.gen(function* () {
+                  const downstream = yield* next()
+                  const downstreamText = (downstream as { text?: string } | undefined)?.text
+                  return { text: downstreamText ?? textCompleteV1.text }
+                }),
+            ])
+            ctx.currentText.text = (textCompleteV2 as { text: string }).text
             {
               const end = Date.now()
               ctx.currentText.time = { start: ctx.currentText.time?.start ?? end, end }
diff --git a/packages/schema/src/session-event.ts b/packages/schema/src/session-event.ts
index 4155781ed5fa..ff292a27f72e 100644
--- a/packages/schema/src/session-event.ts
+++ b/packages/schema/src/session-event.ts
@@ -270,6 +270,24 @@ export namespace Text {
     },
   })
   export type Ended = typeof Ended.Type
+
+  /**
+   * Live waterfall fired when a text part's stream completes, before the
+   * final value is persisted. Listeners return `{ text }` to transform the
+   * final text or throw to veto. This is the V2 replacement for the legacy
+   * V1 `experimental.text.complete` hook and gives plugins proper
+   * `next()`-based mutation semantics.
+   */
+  export const Complete = Event.define({
+    type: "session.next.text.complete",
+    schema: {
+      ...Base,
+      messageID: SessionMessage.ID,
+      partID: Schema.String,
+      text: Schema.String,
+    },
+  })
+  export type Complete = typeof Complete.Type
 }
 
 export namespace Reasoning {