feat(settings): add reasoning effort level for Claude Code

Add an Effort Level dropdown under the Claude Code model inputs with
options Low / Medium / High / Max (Opus only). The selection writes an
"effortLevel" key at the root of the Claude Code config JSON, and is
removed when the default is chosen. Manual edits to the native JSON
textarea stay in sync with the dropdown.

src/components/settings/acp-agent-settings.tsx

@@ -127,6 +127,7 @@ interface AgentDraft {
   claudeDefaultHaikuModel: string
   claudeDefaultSonnetModel: string
   claudeDefaultOpusModel: string
+  claudeEffortLevel: ClaudeEffortLevel
   codexAuthJsonText: string
   codexConfigTomlText: string
   openCodeAuthJsonText: string
@@ -251,6 +252,28 @@ const CLAUDE_MODEL_ENV_KEYS = {
   claudeDefaultOpusModel: "ANTHROPIC_DEFAULT_OPUS_MODEL",
 } as const
 
+const CLAUDE_EFFORT_LEVEL_CONFIG_KEY = "effortLevel"
+
+type ClaudeEffortLevel = "" | "low" | "medium" | "high" | "max"
+
+const CLAUDE_EFFORT_LEVEL_VALUES: ReadonlyArray<
+  Exclude<ClaudeEffortLevel, "">
+> = ["low", "medium", "high", "max"]
+
+function normalizeClaudeEffortLevel(value: unknown): ClaudeEffortLevel {
+  if (typeof value !== "string") return ""
+  const normalized = value.trim().toLowerCase()
+  if (
+    normalized === "low" ||
+    normalized === "medium" ||
+    normalized === "high" ||
+    normalized === "max"
+  ) {
+    return normalized
+  }
+  return ""
+}
+
 const GEMINI_AUTH_MODES = [
   "custom",
   "login_google",
@@ -473,6 +496,7 @@ function extractImportantConfigValues(
   claudeDefaultHaikuModel: string
   claudeDefaultSonnetModel: string
   claudeDefaultOpusModel: string
+  claudeEffortLevel: ClaudeEffortLevel
   configError: string | null
 } {
   const parseResult = parseConfigJsonText(configText)
@@ -507,6 +531,11 @@ function extractImportantConfigValues(
     CLAUDE_MODEL_ENV_KEYS.claudeDefaultOpusModel,
   ])
 
+  const claudeEffortLevel: ClaudeEffortLevel =
+    agentType === "claude_code"
+      ? normalizeClaudeEffortLevel(config[CLAUDE_EFFORT_LEVEL_CONFIG_KEY])
+      : ""
+
   return {
     apiBaseUrl: apiBaseUrl ?? "",
     apiKey: apiKey ?? "",
@@ -520,6 +549,7 @@ function extractImportantConfigValues(
       agentType === "claude_code" ? claudeDefaultSonnetModel : "",
     claudeDefaultOpusModel:
       agentType === "claude_code" ? claudeDefaultOpusModel : "",
+    claudeEffortLevel,
     configError: parseResult.error,
   }
 }
@@ -2318,6 +2348,7 @@ function buildAgentDraft(agent: AcpAgentInfo): AgentDraft {
     claudeDefaultHaikuModel: important.claudeDefaultHaikuModel,
     claudeDefaultSonnetModel: important.claudeDefaultSonnetModel,
     claudeDefaultOpusModel: important.claudeDefaultOpusModel,
+    claudeEffortLevel: important.claudeEffortLevel,
     codexAuthJsonText,
     codexConfigTomlText,
     openCodeAuthJsonText,
@@ -3569,6 +3600,7 @@ export function AcpAgentSettings() {
         claudeDefaultHaikuModel: important.claudeDefaultHaikuModel,
         claudeDefaultSonnetModel: important.claudeDefaultSonnetModel,
         claudeDefaultOpusModel: important.claudeDefaultOpusModel,
+        claudeEffortLevel: important.claudeEffortLevel,
       }))
     },
     [selectedAgent, selectedDraft, updateSelectedDraft]
@@ -3607,6 +3639,41 @@ export function AcpAgentSettings() {
     [selectedAgent, selectedDraft, t, updateSelectedDraft]
   )
 
+  const handleClaudeEffortLevelChange = useCallback(
+    (nextValue: ClaudeEffortLevel) => {
+      if (
+        !selectedAgent ||
+        !selectedDraft ||
+        selectedAgent.agent_type !== "claude_code"
+      )
+        return
+      const parsed = parseConfigJsonText(selectedDraft.configText)
+      if (parsed.error) {
+        toast.warning(t("warnings.nativeJsonRecoveredStructured"))
+      }
+      const config: Record<string, unknown> = parsed.error
+        ? {}
+        : { ...parsed.config }
+      if (nextValue) {
+        config[CLAUDE_EFFORT_LEVEL_CONFIG_KEY] = nextValue
+      } else {
+        delete config[CLAUDE_EFFORT_LEVEL_CONFIG_KEY]
+      }
+      const nextConfigText =
+        Object.keys(config).length === 0 ? "" : JSON.stringify(config, null, 2)
+      setConfigErrors((prev) => ({
+        ...prev,
+        [selectedAgent.agent_type]: null,
+      }))
+      updateSelectedDraft((current) => ({
+        ...current,
+        claudeEffortLevel: nextValue,
+        configText: nextConfigText,
+      }))
+    },
+    [selectedAgent, selectedDraft, t, updateSelectedDraft]
+  )
+
   const handleClaudeAuthModeChange = useCallback(
     (nextMode: ClaudeAuthMode) => {
       if (
@@ -7111,6 +7178,39 @@ supports_websockets = true`}
                         <p className="text-[11px] text-muted-foreground">
                           {t("modelHintDefault")}
                         </p>
+                        <div className="space-y-1.5">
+                          <label className="text-[11px] text-muted-foreground">
+                            {t("claude.effortLevel")}
+                          </label>
+                          <Select
+                            value={selectedDraft.claudeEffortLevel || "default"}
+                            onValueChange={(nextValue) => {
+                              handleClaudeEffortLevelChange(
+                                nextValue === "default"
+                                  ? ""
+                                  : (nextValue as ClaudeEffortLevel)
+                              )
+                            }}
+                          >
+                            <SelectTrigger className="w-full">
+                              <SelectValue
+                                placeholder={t("claude.effortLevelDefault")}
+                              />
+                            </SelectTrigger>
+                            <SelectContent align="start">
+                              <SelectItem value="default">
+                                {t("claude.effortLevelDefault")}
+                              </SelectItem>
+                              {CLAUDE_EFFORT_LEVEL_VALUES.map((value) => (
+                                <SelectItem key={value} value={value}>
+                                  {value === "max"
+                                    ? t("claude.effortLevelMax")
+                                    : t(`claude.effortLevel_${value}`)}
+                                </SelectItem>
+                              ))}
+                            </SelectContent>
+                          </Select>
+                        </div>
                       </div>
                     ) : (
                       <div className="space-y-1.5">

src/i18n/messages/ar.json

@@ -626,7 +626,13 @@
       "reasoningModel": "نموذج الاستدلال (thinking)",
       "haikuDefaultModel": "نموذج Haiku الافتراضي",
       "sonnetDefaultModel": "نموذج Sonnet الافتراضي",
-      "opusDefaultModel": "نموذج Opus الافتراضي"
+      "opusDefaultModel": "نموذج Opus الافتراضي",
+      "effortLevel": "مستوى الاستدلال",
+      "effortLevelDefault": "المستوى الافتراضي",
+      "effortLevel_low": "منخفض",
+      "effortLevel_medium": "متوسط",
+      "effortLevel_high": "مرتفع",
+      "effortLevelMax": "الأقصى (Opus فقط)"
     },
     "dialogs": {
       "confirmDeleteProvider": "حذف المزود {providerId}؟",

src/i18n/messages/de.json

@@ -626,7 +626,13 @@
       "reasoningModel": "Reasoning-Modell (thinking)",
       "haikuDefaultModel": "Standard-Haiku-Modell",
       "sonnetDefaultModel": "Standard-Sonnet-Modell",
-      "opusDefaultModel": "Standard-Opus-Modell"
+      "opusDefaultModel": "Standard-Opus-Modell",
+      "effortLevel": "Reasoning-Stufe",
+      "effortLevelDefault": "Standardstufe",
+      "effortLevel_low": "Niedrig",
+      "effortLevel_medium": "Mittel",
+      "effortLevel_high": "Hoch",
+      "effortLevelMax": "Maximum (nur Opus)"
     },
     "dialogs": {
       "confirmDeleteProvider": "Provider {providerId} löschen?",

src/i18n/messages/en.json

@@ -626,7 +626,13 @@
       "reasoningModel": "Reasoning Model (thinking)",
       "haikuDefaultModel": "Default Haiku Model",
       "sonnetDefaultModel": "Default Sonnet Model",
-      "opusDefaultModel": "Default Opus Model"
+      "opusDefaultModel": "Default Opus Model",
+      "effortLevel": "Reasoning Effort Level",
+      "effortLevelDefault": "Default Level",
+      "effortLevel_low": "Low",
+      "effortLevel_medium": "Medium",
+      "effortLevel_high": "High",
+      "effortLevelMax": "Max (Opus only)"
     },
     "dialogs": {
       "confirmDeleteProvider": "Delete Provider {providerId}?",

src/i18n/messages/es.json

@@ -626,7 +626,13 @@
       "reasoningModel": "Modelo de razonamiento (thinking)",
       "haikuDefaultModel": "Modelo Haiku predeterminado",
       "sonnetDefaultModel": "Modelo Sonnet predeterminado",
-      "opusDefaultModel": "Modelo Opus predeterminado"
+      "opusDefaultModel": "Modelo Opus predeterminado",
+      "effortLevel": "Nivel de razonamiento",
+      "effortLevelDefault": "Nivel predeterminado",
+      "effortLevel_low": "Bajo",
+      "effortLevel_medium": "Medio",
+      "effortLevel_high": "Alto",
+      "effortLevelMax": "Máximo (solo Opus)"
     },
     "dialogs": {
       "confirmDeleteProvider": "¿Eliminar proveedor {providerId}?",

src/i18n/messages/fr.json

@@ -626,7 +626,13 @@
       "reasoningModel": "Modèle de raisonnement (thinking)",
       "haikuDefaultModel": "Modèle Haiku par défaut",
       "sonnetDefaultModel": "Modèle Sonnet par défaut",
-      "opusDefaultModel": "Modèle Opus par défaut"
+      "opusDefaultModel": "Modèle Opus par défaut",
+      "effortLevel": "Niveau de raisonnement",
+      "effortLevelDefault": "Niveau par défaut",
+      "effortLevel_low": "Bas",
+      "effortLevel_medium": "Moyen",
+      "effortLevel_high": "Élevé",
+      "effortLevelMax": "Maximum (Opus uniquement)"
     },
     "dialogs": {
       "confirmDeleteProvider": "Supprimer le provider {providerId} ?",

src/i18n/messages/ja.json

@@ -626,7 +626,13 @@
       "reasoningModel": "推論モデル（thinking）",
       "haikuDefaultModel": "デフォルト Haiku モデル",
       "sonnetDefaultModel": "デフォルト Sonnet モデル",
-      "opusDefaultModel": "デフォルト Opus モデル"
+      "opusDefaultModel": "デフォルト Opus モデル",
+      "effortLevel": "推論レベル",
+      "effortLevelDefault": "デフォルトレベル",
+      "effortLevel_low": "低",
+      "effortLevel_medium": "中",
+      "effortLevel_high": "高",
+      "effortLevelMax": "最大（Opus のみ対応）"
     },
     "dialogs": {
       "confirmDeleteProvider": "Provider {providerId} を削除しますか？",

src/i18n/messages/ko.json

@@ -626,7 +626,13 @@
       "reasoningModel": "추론 모델 (thinking)",
       "haikuDefaultModel": "기본 Haiku 모델",
       "sonnetDefaultModel": "기본 Sonnet 모델",
-      "opusDefaultModel": "기본 Opus 모델"
+      "opusDefaultModel": "기본 Opus 모델",
+      "effortLevel": "추론 수준",
+      "effortLevelDefault": "기본 수준",
+      "effortLevel_low": "낮음",
+      "effortLevel_medium": "중간",
+      "effortLevel_high": "높음",
+      "effortLevelMax": "최고 (Opus만 지원)"
     },
     "dialogs": {
       "confirmDeleteProvider": "Provider {providerId}를 삭제하시겠습니까?",

src/i18n/messages/pt.json

@@ -626,7 +626,13 @@
       "reasoningModel": "Modelo de raciocínio (thinking)",
       "haikuDefaultModel": "Modelo Haiku padrão",
       "sonnetDefaultModel": "Modelo Sonnet padrão",
-      "opusDefaultModel": "Modelo Opus padrão"
+      "opusDefaultModel": "Modelo Opus padrão",
+      "effortLevel": "Nível de raciocínio",
+      "effortLevelDefault": "Nível padrão",
+      "effortLevel_low": "Baixo",
+      "effortLevel_medium": "Médio",
+      "effortLevel_high": "Alto",
+      "effortLevelMax": "Máximo (apenas Opus)"
     },
     "dialogs": {
       "confirmDeleteProvider": "Excluir o provedor {providerId}?",

src/i18n/messages/zh-CN.json

@@ -626,7 +626,13 @@
       "reasoningModel": "推理模型（thinking）",
       "haikuDefaultModel": "Haiku 默认模型",
       "sonnetDefaultModel": "Sonnet 默认模型",
-      "opusDefaultModel": "Opus 默认模型"
+      "opusDefaultModel": "Opus 默认模型",
+      "effortLevel": "推理级别",
+      "effortLevelDefault": "默认级别",
+      "effortLevel_low": "低",
+      "effortLevel_medium": "中",
+      "effortLevel_high": "高",
+      "effortLevelMax": "最高（仅 Opus 支持）"
     },
     "dialogs": {
       "confirmDeleteProvider": "确认删除 Provider {providerId}？",

src/i18n/messages/zh-TW.json

@@ -626,7 +626,13 @@
       "reasoningModel": "推理模型（thinking）",
       "haikuDefaultModel": "Haiku 預設模型",
       "sonnetDefaultModel": "Sonnet 預設模型",
-      "opusDefaultModel": "Opus 預設模型"
+      "opusDefaultModel": "Opus 預設模型",
+      "effortLevel": "推理等級",
+      "effortLevelDefault": "預設等級",
+      "effortLevel_low": "低",
+      "effortLevel_medium": "中",
+      "effortLevel_high": "高",
+      "effortLevelMax": "最高（僅 Opus 支援）"
     },
     "dialogs": {
       "confirmDeleteProvider": "確認刪除 Provider {providerId}？",