Merge pull request #4133 from code-yeongyu/fix/3816-frozen-output-args

fix: replace direct output.args mutation with replaceToolArgs helper (fixes #3816)

src/hooks/atlas/tool-execute-before.ts

@@ -1,4 +1,5 @@
 import { log } from "../../shared/logger"
+import { replaceToolArgs } from "../../shared/replace-tool-args"
 import { SYSTEM_DIRECTIVE_PREFIX } from "../../shared/system-directive"
 import { isCallerOrchestrator } from "../../shared/session-utils"
 import type { PluginInput } from "@opencode-ai/plugin"
@@ -179,7 +180,7 @@ export function createToolExecuteBeforeHandler(input: {
 
       const prompt = toolOutput.args.prompt as string | undefined
       if (prompt && !prompt.includes(SYSTEM_DIRECTIVE_PREFIX)) {
-        toolOutput.args.prompt = `<system-reminder>${SINGLE_TASK_DIRECTIVE}</system-reminder>\n` + prompt
+        replaceToolArgs(toolOutput, { prompt: `<system-reminder>${SINGLE_TASK_DIRECTIVE}</system-reminder>\n` + prompt })
         log(`[${HOOK_NAME}] Injected single-task directive to task`, {
           sessionID: toolInput.sessionID,
         })

src/hooks/claude-code-hooks/handlers/tool-execute-before-handler.ts

@@ -8,7 +8,7 @@ import {
 import { appendTranscriptEntry } from "../transcript"
 import { cacheToolInput } from "../tool-input-cache"
 import type { PluginConfig } from "../types"
-import { isHookDisabled, log } from "../../../shared"
+import { isHookDisabled, log, replaceToolArgs } from "../../../shared"
 
 export function createToolExecuteBeforeHandler(ctx: PluginInput, config: PluginConfig) {
 	return async (
@@ -39,7 +39,7 @@ export function createToolExecuteBeforeHandler(ctx: PluginInput, config: PluginC
 				)
 			}
 
-			output.args.todos = parsed
+			replaceToolArgs(output, { todos: parsed })
 			log("todowrite: parsed todos string to array", { sessionID: input.sessionID })
 		}
 
@@ -87,7 +87,7 @@ export function createToolExecuteBeforeHandler(ctx: PluginInput, config: PluginC
 		}
 
 		if (result.modifiedInput) {
-			Object.assign(output.args, result.modifiedInput)
+			replaceToolArgs(output, result.modifiedInput as Record<string, unknown>)
 		}
 	}
 }

src/hooks/compaction-todo-preserver/hook.ts

@@ -1,6 +1,7 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { resolveSessionEventID } from "../../shared/event-session-id"
 import { log } from "../../shared/logger"
+import { replaceToolArgs } from "../../shared/replace-tool-args"
 
 interface TodoSnapshot {
   id?: string
@@ -233,7 +234,7 @@ export function createCompactionTodoPreserverHook(
       return
     }
 
-    output.args.todos = snapshot
+    replaceToolArgs(output, { todos: snapshot })
     log(`[${HOOK_NAME}] Replaced late Atlas bootstrap todowrite with restored snapshot`, {
       sessionID: input.sessionID,
       count: snapshot.length,

src/hooks/non-interactive-env/non-interactive-env-hook.ts

@@ -1,6 +1,6 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { HOOK_NAME, NON_INTERACTIVE_ENV, SHELL_COMMAND_PATTERNS } from "./constants"
-import { log, buildEnvPrefix } from "../../shared"
+import { log, buildEnvPrefix, replaceToolArgs } from "../../shared"
 import { detectShellType, type ShellType } from "../../shared/shell-env"
 
 export * from "./constants"
@@ -97,7 +97,7 @@ export function createNonInteractiveEnvHook(_ctx: PluginInput) {
         return
       }
 
-      output.args.command = `${envPrefix} ${command}`
+      replaceToolArgs(output, { command: `${envPrefix} ${command}` })
 
       log(`[${HOOK_NAME}] Prepended non-interactive env vars to git command`, {
         sessionID: input.sessionID,

src/hooks/prometheus-md-only/hook.ts

@@ -1,6 +1,7 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { HOOK_NAME, BLOCKED_TOOLS, PLANNING_CONSULT_WARNING, PROMETHEUS_WORKFLOW_REMINDER } from "./constants"
 import { log } from "../../shared/logger"
+import { replaceToolArgs } from "../../shared/replace-tool-args"
 import { SYSTEM_DIRECTIVE_PREFIX } from "../../shared/system-directive"
 import { getAgentDisplayName } from "../../shared/agent-display-names"
 import { getAgentFromSession } from "./agent-resolution"
@@ -27,7 +28,7 @@ export function createPrometheusMdOnlyHook(ctx: PluginInput) {
        if (TASK_TOOLS.includes(toolName)) {
          const prompt = output.args.prompt as string | undefined
          if (prompt && !prompt.includes(SYSTEM_DIRECTIVE_PREFIX)) {
-           output.args.prompt = PLANNING_CONSULT_WARNING + prompt
+           replaceToolArgs(output, { prompt: PLANNING_CONSULT_WARNING + prompt })
           log(`[${HOOK_NAME}] Injected planning warning to ${toolName}`, {
             sessionID: input.sessionID,
             tool: toolName,

src/hooks/question-label-truncator/hook.ts

@@ -1,3 +1,5 @@
+import { replaceToolArgs } from "../../shared/replace-tool-args"
+
 const MAX_LABEL_LENGTH = 30;
 
 interface QuestionOption {
@@ -56,7 +58,7 @@ export function createQuestionLabelTruncatorHook() {
       if (toolName === "askuserquestion" || toolName === "ask_user_question") {
         if (hasQuestions(output.args)) {
           const truncatedArgs = truncateQuestionLabels(output.args);
-          Object.assign(output.args, truncatedArgs);
+          replaceToolArgs(output, { questions: truncatedArgs.questions });
         }
       }
     },

src/hooks/sisyphus-junior-notepad/hook.ts

@@ -3,6 +3,7 @@ import type { PluginInput } from "@opencode-ai/plugin"
 import { isCallerOrchestrator } from "../../shared/session-utils"
 import { SYSTEM_DIRECTIVE_PREFIX } from "../../shared/system-directive"
 import { log } from "../../shared/logger"
+import { replaceToolArgs } from "../../shared/replace-tool-args"
 import { HOOK_NAME, NOTEPAD_DIRECTIVE } from "./constants"
 
 export function createSisyphusJuniorNotepadHook(ctx: PluginInput) {
@@ -33,7 +34,7 @@ export function createSisyphusJuniorNotepadHook(ctx: PluginInput) {
       }
 
       // 5. Prepend directive
-      output.args.prompt = NOTEPAD_DIRECTIVE + prompt
+      replaceToolArgs(output, { prompt: NOTEPAD_DIRECTIVE + prompt })
 
       // 6. Log injection
       log(`[${HOOK_NAME}] Injected notepad directive to task`, {

src/hooks/webfetch-redirect-guard/hook.ts

@@ -1,5 +1,5 @@
 import type { PluginInput } from "@opencode-ai/plugin"
-import { log } from "../../shared"
+import { log, replaceToolArgs } from "../../shared"
 import {
   MAX_WEBFETCH_REDIRECTS,
   WEBFETCH_REDIRECT_ERROR_PATTERNS,
@@ -85,7 +85,7 @@ export function createWebFetchRedirectGuardHook(_ctx: PluginInput) {
         })
 
         if (resolution.type === "resolved") {
-          output.args.url = resolution.url
+          replaceToolArgs(output, { url: resolution.url })
           return
         }