diff --git a/src/features/builtin-commands/commands.ts b/src/features/builtin-commands/commands.ts
index f489c198b..d4e10903b 100644
--- a/src/features/builtin-commands/commands.ts
+++ b/src/features/builtin-commands/commands.ts
@@ -55,7 +55,7 @@ ${REFACTOR_TEMPLATE}
   },
   "start-work": {
     description: "(builtin) Start Sisyphus work session from Prometheus plan",
-    agent: "orchestrator-sisyphus",
+    agent: "atlas",
     template: `<command-instruction>
 ${START_WORK_TEMPLATE}
 </command-instruction>
diff --git a/src/hooks/atlas/index.ts b/src/hooks/atlas/index.ts
index 859b462e2..e36175d84 100644
--- a/src/hooks/atlas/index.ts
+++ b/src/hooks/atlas/index.ts
@@ -569,7 +569,7 @@ export function createSisyphusOrchestratorHook(
         }
 
         if (!isCallerOrchestrator(sessionID)) {
-          log(`[${HOOK_NAME}] Skipped: last agent is not orchestrator-sisyphus`, { sessionID })
+          log(`[${HOOK_NAME}] Skipped: last agent is not atlas`, { sessionID })
           return
         }
 
diff --git a/src/hooks/start-work/index.test.ts b/src/hooks/start-work/index.test.ts
index 7731649a0..c13b5193f 100644
--- a/src/hooks/start-work/index.test.ts
+++ b/src/hooks/start-work/index.test.ts
@@ -379,7 +379,7 @@ describe("start-work hook", () => {
   })
 
   describe("session agent management", () => {
-    test("should update session agent to orchestrator-sisyphus when start-work command is triggered", async () => {
+    test("should update session agent to atlas when start-work command is triggered", async () => {
       // #given
       const updateSpy = spyOn(sessionState, "updateSessionAgent")
       
@@ -395,7 +395,7 @@ describe("start-work hook", () => {
       )
 
       // #then
-      expect(updateSpy).toHaveBeenCalledWith("ses-prometheus-to-sisyphus", "orchestrator-sisyphus")
+      expect(updateSpy).toHaveBeenCalledWith("ses-prometheus-to-sisyphus", "atlas")
       updateSpy.mockRestore()
     })
   })
diff --git a/src/hooks/start-work/index.ts b/src/hooks/start-work/index.ts
index 704435a5e..4f3d528b2 100644
--- a/src/hooks/start-work/index.ts
+++ b/src/hooks/start-work/index.ts
@@ -71,7 +71,7 @@ export function createStartWorkHook(ctx: PluginInput) {
         sessionID: input.sessionID,
       })
 
-      updateSessionAgent(input.sessionID, "orchestrator-sisyphus")
+      updateSessionAgent(input.sessionID, "atlas")
 
       const existingState = readBoulderState(ctx.directory)
       const sessionId = input.sessionID
diff --git a/src/plugin-handlers/config-handler.ts b/src/plugin-handlers/config-handler.ts
index b8c4388ed..948df8c39 100644
--- a/src/plugin-handlers/config-handler.ts
+++ b/src/plugin-handlers/config-handler.ts
@@ -160,7 +160,7 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
       explore?: { tools?: Record<string, unknown> };
       librarian?: { tools?: Record<string, unknown> };
       "multimodal-looker"?: { tools?: Record<string, unknown> };
-      "orchestrator-sisyphus"?: { tools?: Record<string, unknown> };
+      atlas?: { tools?: Record<string, unknown> };
       Sisyphus?: { tools?: Record<string, unknown> };
     };
     const configAgent = config.agent as AgentConfig | undefined;
@@ -319,8 +319,8 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
       const agent = agentResult["multimodal-looker"] as AgentWithPermission;
       agent.permission = { ...agent.permission, task: "deny", look_at: "deny" };
     }
-    if (agentResult["orchestrator-sisyphus"]) {
-      const agent = agentResult["orchestrator-sisyphus"] as AgentWithPermission;
+    if (agentResult["atlas"]) {
+      const agent = agentResult["atlas"] as AgentWithPermission;
       agent.permission = { ...agent.permission, task: "deny", call_omo_agent: "deny", delegate_task: "allow" };
     }
     if (agentResult.Sisyphus) {
diff --git a/src/tools/delegate-task/tools.test.ts b/src/tools/delegate-task/tools.test.ts
index 301ff3a59..25d1d0e88 100644
--- a/src/tools/delegate-task/tools.test.ts
+++ b/src/tools/delegate-task/tools.test.ts
@@ -894,17 +894,29 @@ describe("sisyphus-task", () => {
   })
 
   describe("modelInfo detection via resolveCategoryConfig", () => {
-    test("systemDefaultModel is used when no userModel and no inheritedModel", () => {
-      // #given - builtin category, no user model, no inherited model
+    test("catalog model is used for category with catalog entry", () => {
+      // #given - ultrabrain has catalog entry
       const categoryName = "ultrabrain"
       
       // #when
       const resolved = resolveCategoryConfig(categoryName, { systemDefaultModel: SYSTEM_DEFAULT_MODEL })
       
-      // #then - actualModel should be systemDefaultModel (categories no longer have model defaults)
+      // #then - catalog model is used
       expect(resolved).not.toBeNull()
-      const actualModel = resolved!.config.model
-      expect(actualModel).toBe(SYSTEM_DEFAULT_MODEL)
+      expect(resolved!.config.model).toBe("openai/gpt-5.2-codex")
+      expect(resolved!.config.variant).toBe("xhigh")
+    })
+
+    test("systemDefaultModel is used for category without catalog entry", () => {
+      // #given - general has no catalog entry
+      const categoryName = "general"
+      
+      // #when
+      const resolved = resolveCategoryConfig(categoryName, { systemDefaultModel: SYSTEM_DEFAULT_MODEL })
+      
+      // #then - systemDefaultModel is used
+      expect(resolved).not.toBeNull()
+      expect(resolved!.config.model).toBe(SYSTEM_DEFAULT_MODEL)
     })
 
     test("inheritedModel takes precedence over systemDefaultModel for builtin category", () => {
diff --git a/src/tools/delegate-task/tools.ts b/src/tools/delegate-task/tools.ts
index 28b40b6d1..5f5b075c1 100644
--- a/src/tools/delegate-task/tools.ts
+++ b/src/tools/delegate-task/tools.ts
@@ -118,22 +118,24 @@ export function resolveCategoryConfig(
   const { userCategories, inheritedModel, systemDefaultModel } = options
   const defaultConfig = DEFAULT_CATEGORIES[categoryName]
   const userConfig = userCategories?.[categoryName]
+  const catalogEntry = CATEGORY_MODEL_CATALOG[categoryName]
   const defaultPromptAppend = CATEGORY_PROMPT_APPENDS[categoryName] ?? ""
 
   if (!defaultConfig && !userConfig) {
     return null
   }
 
-  // Model priority: user override > inherited from parent > system default
+  // Model priority: user override > inherited from parent > catalog default > system default
   const model = resolveModel({
     userModel: userConfig?.model,
     inheritedModel,
-    systemDefault: systemDefaultModel,
+    systemDefault: catalogEntry?.model ?? systemDefaultModel,
   })
   const config: CategoryConfig = {
     ...defaultConfig,
     ...userConfig,
     model,
+    variant: userConfig?.variant ?? catalogEntry?.variant,
   }
 
   let promptAppend = defaultPromptAppend