feat: add per-cron-job model tier selection

Allow cron jobs to specify a `model_tier` field that controls which LLM
tier handles the job, without needing separate agent configs. Precedence:
cron job model_tier > agent config > global primary_tier > 'default'.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/daemon/routing.test.ts

@@ -1,6 +1,7 @@
 import { describe, it, expect } from 'vitest';
 import { AgentRouter } from '../agents/router.js';
 import { AgentConfigRegistry } from '../agents/registry.js';
+import type { ModelTier } from '../models/router.js';
 
 describe('daemon agent routing integration', () => {
   it('resolves agent config for channel messages', () => {
@@ -35,4 +36,28 @@ describe('daemon agent routing integration', () => {
     const router = new AgentRouter({ channels: {}, senders: {} });
     expect(router.resolve('telegram', '123')).toBeUndefined();
   });
+
+  it('model tier precedence: metadata > agent config > global default', () => {
+    // This test documents the tier resolution precedence used by createMessageRouter.
+    // The actual resolution logic: tierFromMetadata ?? agentConfig?.modelTier ?? primary_tier ?? 'default'
+    function resolveTier(
+      metadataTier: ModelTier | undefined,
+      agentTier: ModelTier | undefined,
+      globalTier: ModelTier | undefined,
+    ): ModelTier {
+      return metadataTier ?? agentTier ?? globalTier ?? 'default';
+    }
+
+    // With all three set, metadata wins
+    expect(resolveTier('fast', 'complex', 'default')).toBe('fast');
+
+    // Without metadata, agent config wins
+    expect(resolveTier(undefined, 'complex', 'default')).toBe('complex');
+
+    // Without metadata or agent config, global wins
+    expect(resolveTier(undefined, undefined, 'default')).toBe('default');
+
+    // Without anything, falls back to 'default'
+    expect(resolveTier(undefined, undefined, undefined)).toBe('default');
+  });
 });

src/daemon/routing.ts

@@ -9,7 +9,7 @@ import type { Tool } from '../tools/types.js';
 import { createMediaSendTool } from '../tools/index.js';
 import { createSandboxedShellTool, createSandboxedProcessStartTool, SandboxManager } from '../sandbox/index.js';
 import type { Config } from '../config/index.js';
-import { ModelRouter } from '../models/index.js';
+import { ModelRouter, type ModelTier } from '../models/index.js';
 import { ToolRegistry, ToolExecutor } from '../tools/index.js';
 import { SessionManager } from '../session/index.js';
 import { AgentConfigRegistry, AgentRouter } from '../agents/index.js';
@@ -40,15 +40,19 @@ export function createMessageRouter(deps: {
   // Cache agents by session ID + agent config name to avoid recreating on every message
   const agents = new Map<string, { orchestrator: AgentOrchestrator; collector: OutboundAttachmentCollector }>();
 
-  function getOrCreateAgent(channel: string, senderId: string): { orchestrator: AgentOrchestrator; collector: OutboundAttachmentCollector } {
+  function getOrCreateAgent(channel: string, senderId: string, metadata?: Record<string, unknown>): { orchestrator: AgentOrchestrator; collector: OutboundAttachmentCollector } {
     // Resolve agent config name via routing (sender → channel → default fallback)
     const agentConfigName = deps.agentRouter?.resolve(channel, senderId);
     const agentConfig = agentConfigName ? deps.agentConfigRegistry?.get(agentConfigName) : undefined;
 
+    // Cron job tier wins over agent config tier
+    const tierFromMetadata = metadata?.modelTier as ModelTier | undefined;
+
     // Include agent config name in cache key so different agents aren't shared
-    const sessionId = agentConfigName
+    const baseSid = agentConfigName
       ? `${channel}:${senderId}:${agentConfigName}`
       : `${channel}:${senderId}`;
+    const sessionId = tierFromMetadata ? `${baseSid}:${tierFromMetadata}` : baseSid;
 
     let entry = agents.get(sessionId);
     if (!entry) {
@@ -56,7 +60,7 @@ export function createMessageRouter(deps: {
 
       // Use agent config overrides where available, falling back to global config
       const effectiveSystemPrompt = agentConfig?.systemPrompt ?? deps.systemPrompt;
-      const effectiveTier = agentConfig?.modelTier ?? deps.config.agents.primary_tier ?? 'default';
+      const effectiveTier = tierFromMetadata ?? agentConfig?.modelTier ?? deps.config.agents.primary_tier ?? 'default';
       const effectiveProvider = deps.config.models.default.provider;
 
       const delegationConfig: DelegationConfig = {
@@ -156,7 +160,7 @@ export function createMessageRouter(deps: {
   }
 
   const handler = async (msg: InboundMessage, reply: (response: OutboundMessage) => Promise<void>): Promise<void> => {
-    const { orchestrator: agent, collector } = getOrCreateAgent(msg.channel, msg.senderId);
+    const { orchestrator: agent, collector } = getOrCreateAgent(msg.channel, msg.senderId, msg.metadata);
 
     // Handle special commands
     if (msg.metadata?.isCommand) {