fix: CRITICAL FOR COPILOT USERS | moving to use completed assistant message and tool part to inject prunable tools list

Author: spoons-and-mirrors

lib/messages/inject.ts

@@ -3,7 +3,11 @@ import type { Logger } from "../logger"
 import type { PluginConfig } from "../config"
 import type { UserMessage } from "@opencode-ai/sdk/v2"
 import { loadPrompt } from "../prompts"
-import { extractParameterKey, buildToolIdList, createSyntheticUserMessage } from "./utils"
+import {
+    extractParameterKey,
+    buildToolIdList,
+    createSyntheticAssistantMessageWithToolPart,
+} from "./utils"
 import { getFilePathFromParameters, isProtectedFilePath } from "../protected-file-patterns"
 import { getLastUserMessage } from "../shared-utils"
 
@@ -132,6 +136,7 @@ export const insertPruneToolContext = (
     if (!lastUserMessage) {
         return
     }
-    const variant = state.variant ?? (lastUserMessage.info as UserMessage).variant
-    messages.push(createSyntheticUserMessage(lastUserMessage, prunableToolsContent, variant))
+    messages.push(
+        createSyntheticAssistantMessageWithToolPart(lastUserMessage, prunableToolsContent),
+    )
 }

lib/messages/utils.ts

@@ -5,6 +5,7 @@ import type { UserMessage } from "@opencode-ai/sdk/v2"
 
 const SYNTHETIC_MESSAGE_ID = "msg_01234567890123456789012345"
 const SYNTHETIC_PART_ID = "prt_01234567890123456789012345"
+const SYNTHETIC_CALL_ID = "call_01234567890123456789012345"
 
 export const createSyntheticUserMessage = (
     baseMessage: WithParts,
@@ -37,6 +38,50 @@ export const createSyntheticUserMessage = (
     }
 }
 
+export const createSyntheticAssistantMessageWithToolPart = (
+    baseMessage: WithParts,
+    content: string,
+): WithParts => {
+    const userInfo = baseMessage.info as UserMessage
+    const now = Date.now()
+    return {
+        info: {
+            id: SYNTHETIC_MESSAGE_ID,
+            sessionID: userInfo.sessionID,
+            role: "assistant",
+            parentID: userInfo.id,
+            modelID: userInfo.model.modelID,
+            providerID: userInfo.model.providerID,
+            mode: "default",
+            path: {
+                cwd: "/",
+                root: "/",
+            },
+            time: { created: now, completed: now },
+            cost: 0,
+            tokens: { input: 0, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
+        },
+        parts: [
+            {
+                id: SYNTHETIC_PART_ID,
+                sessionID: userInfo.sessionID,
+                messageID: SYNTHETIC_MESSAGE_ID,
+                type: "tool",
+                callID: SYNTHETIC_CALL_ID,
+                tool: "context_info",
+                state: {
+                    status: "completed",
+                    input: {},
+                    output: content,
+                    title: "Context Info",
+                    metadata: {},
+                    time: { start: now, end: now },
+                },
+            },
+        ],
+    }
+}
+
 /**
  * Extracts a human-readable key from tool metadata for display purposes.
  */

lib/strategies/utils.ts

@@ -28,7 +28,7 @@ export function getCurrentParams(
     const agent: string = userInfo.agent
     const providerId: string | undefined = userInfo.model.providerID
     const modelId: string | undefined = userInfo.model.modelID
-    const variant: string | undefined = state.variant ?? userInfo.variant
+    const variant: string | undefined = state.variant
 
     return { providerId, modelId, agent, variant }
 }