fix(tool-pair-validator): continue after synthetic repairs

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/hooks/tool-pair-validator/hook.test.ts

@@ -9,6 +9,7 @@ import { createToolPairValidatorHook } from "./hook"
 import { _resetForTesting, subagentSessions } from "../../features/claude-code-session-state/state"
 
 const TOOL_RESULT_PLACEHOLDER = "Tool output unavailable (context compacted)"
+const TOOL_RESULT_RECOVERY_CONTINUATION = "Recovered missing tool results. Continue from the repaired tool output."
 
 type TestPart = {
   type: string
@@ -19,6 +20,7 @@ type TestPart = {
   isError?: boolean
   content?: string | Array<{ type: "text"; text: string }>
   text?: string
+  synthetic?: boolean
 }
 
 type TestMessage = {
@@ -121,6 +123,11 @@ describe("createToolPairValidatorHook", () => {
             isError: true,
             content: [{ type: "text", text: TOOL_RESULT_PLACEHOLDER }],
           },
+          {
+            type: "text",
+            text: TOOL_RESULT_RECOVERY_CONTINUATION,
+            synthetic: true,
+          },
         ],
       },
     ])
@@ -148,6 +155,10 @@ describe("createToolPairValidatorHook", () => {
           tool_use_id: "toolu_1",
           isError: true,
           content: [{ type: "text", text: TOOL_RESULT_PLACEHOLDER }],
+        }, {
+          type: "text",
+          text: TOOL_RESULT_RECOVERY_CONTINUATION,
+          synthetic: true,
         }],
       },
       { info: { role: "assistant" }, parts: [{ type: "text", text: "follow-up" }] },

src/hooks/tool-pair-validator/hook.ts

@@ -4,6 +4,7 @@ import { subagentSessions } from "../../features/claude-code-session-state"
 import { log } from "../../shared/logger"
 
 const TOOL_RESULT_PLACEHOLDER = "Tool output unavailable (context compacted)"
+const TOOL_RESULT_RECOVERY_CONTINUATION = "Recovered missing tool results. Continue from the repaired tool output."
 
 type ToolUsePart = {
   type: "tool_use"
@@ -20,7 +21,13 @@ type ToolResultPart = {
   [key: string]: unknown
 }
 
-type TransformPart = Part | ToolUsePart | ToolResultPart
+type TextPart = {
+  type: "text"
+  text: string
+  synthetic: true
+}
+
+type TransformPart = Part | ToolUsePart | ToolResultPart | TextPart
 
 type TransformMessageInfo = Message | {
   role: "user"
@@ -138,7 +145,14 @@ function createSyntheticUserMessage(assistantMessage: MessageWithParts, missingT
       role: "user",
       ...(sessionID ? { sessionID } : {}),
     },
-    parts: missingToolUseIDs.map((toolUseID) => createToolResultPart(toolUseID)),
+    parts: [
+      ...missingToolUseIDs.map((toolUseID) => createToolResultPart(toolUseID)),
+      {
+        type: "text",
+        text: TOOL_RESULT_RECOVERY_CONTINUATION,
+        synthetic: true,
+      },
+    ],
   }
 }
 

src/plugin/messages-transform.test.ts

@@ -157,6 +157,10 @@ describe("createMessagesTransformHandler", () => {
         tool_use_id: "toolu_01SRMQs3DUtVKWoSxC8bxxVA",
         isError: true,
         content: [{ type: "text", text: "Tool output unavailable (context compacted)" }],
+      }, {
+        type: "text",
+        text: "Recovered missing tool results. Continue from the repaired tool output.",
+        synthetic: true,
       }],
     })
     expect(messages[4]?.parts[0]).toEqual({