add parent id to assistant messages

3 files changed, 10 insertions, 4 deletions

diff --git a/packages/opencode/src/session/compaction.ts b/packages/opencode/src/session/compaction.ts
index e3041b40a..2209fda56 100644
--- a/packages/opencode/src/session/compaction.ts
+++ b/packages/opencode/src/session/compaction.ts
@@ -109,6 +109,7 @@ export namespace SessionCompaction {
     const msg = (await Session.updateMessage({
       id: Identifier.ascending("message"),
       role: "assistant",
+      parentID: toSummarize.findLast((m) => m.info.role === "user")?.info.id!,
       sessionID: input.sessionID,
       system,
       mode: "build",
diff --git a/packages/opencode/src/session/message-v2.ts b/packages/opencode/src/session/message-v2.ts
index 1c56cef37..1b17764a5 100644
--- a/packages/opencode/src/session/message-v2.ts
+++ b/packages/opencode/src/session/message-v2.ts
@@ -278,6 +278,7 @@ export namespace MessageV2 {
       ])
       .optional(),
     system: z.string().array(),
+    parentID: z.string(),
     modelID: z.string(),
     providerID: z.string(),
     mode: z.string(),
@@ -346,6 +347,7 @@ export namespace MessageV2 {
     if (v1.role === "assistant") {
       const info: Assistant = {
         id: v1.id,
+        parentID: "",
         sessionID: v1.metadata.sessionID,
         role: "assistant",
         time: {
diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
index fa9d7f633..717fbc241 100644
--- a/packages/opencode/src/session/prompt.ts
+++ b/packages/opencode/src/session/prompt.ts
@@ -235,7 +235,7 @@ export namespace SessionPrompt {
           modelID: model.info.id,
         })
       step++
-      await processor.next()
+      await processor.next(msgs.findLast((m) => m.info.role === "user")?.info.id!)
       await using _ = defer(async () => {
         await processor.end()
       })
@@ -900,9 +900,10 @@ export namespace SessionPrompt {
     let snapshot: string | undefined
     let blocked = false
 
-    async function createMessage() {
+    async function createMessage(parentID: string) {
       const msg: MessageV2.Info = {
         id: Identifier.ascending("message"),
+        parentID,
         role: "assistant",
         system: input.system,
         mode: input.agent,
@@ -938,11 +939,11 @@ export namespace SessionPrompt {
           assistantMsg = undefined
         }
       },
-      async next() {
+      async next(parentID: string) {
         if (assistantMsg) {
           throw new Error("end previous assistant message first")
         }
-        assistantMsg = await createMessage()
+        assistantMsg = await createMessage(parentID)
         return assistantMsg
       },
       get message() {
@@ -1424,6 +1425,7 @@ export namespace SessionPrompt {
     const msg: MessageV2.Assistant = {
       id: Identifier.ascending("message"),
       sessionID: input.sessionID,
+      parentID: userMsg.id,
       system: [],
       mode: input.agent,
       cost: 0,
@@ -1696,6 +1698,7 @@ export namespace SessionPrompt {
       const assistantMsg: MessageV2.Assistant = {
         id: Identifier.ascending("message"),
         sessionID: input.sessionID,
+        parentID: userMsg.id,
         system: [],
         mode: agentName,
         cost: 0,