fix(server): decouple explicit and auto agent title limits (#78)

packages/server/src/shared/messages.create-agent-client-message-id.test.ts

@@ -1,5 +1,6 @@
 import { describe, expect, it } from "vitest";
 import { SessionInboundMessageSchema } from "./messages";
+import { MAX_EXPLICIT_AGENT_TITLE_CHARS } from "../server/agent/agent-title-limits.js";
 
 describe("create_agent_request clientMessageId", () => {
   it("accepts clientMessageId for stable initial prompt transfer", () => {
@@ -20,4 +21,36 @@ describe("create_agent_request clientMessageId", () => {
     }
     expect(parsed.clientMessageId).toBe("client-msg-1");
   });
+
+  it("accepts explicit titles up to the create-agent limit", () => {
+    const parsed = SessionInboundMessageSchema.parse({
+      type: "create_agent_request",
+      requestId: "req-title-ok",
+      config: {
+        provider: "claude",
+        cwd: "/tmp/project",
+        title: "x".repeat(MAX_EXPLICIT_AGENT_TITLE_CHARS),
+      },
+    });
+
+    expect(parsed.type).toBe("create_agent_request");
+    if (parsed.type !== "create_agent_request") {
+      throw new Error("Expected create_agent_request");
+    }
+    expect(parsed.config.title).toHaveLength(MAX_EXPLICIT_AGENT_TITLE_CHARS);
+  });
+
+  it("rejects explicit titles longer than the create-agent limit", () => {
+    const parsed = SessionInboundMessageSchema.safeParse({
+      type: "create_agent_request",
+      requestId: "req-title-too-long",
+      config: {
+        provider: "claude",
+        cwd: "/tmp/project",
+        title: "x".repeat(MAX_EXPLICIT_AGENT_TITLE_CHARS + 1),
+      },
+    });
+
+    expect(parsed.success).toBe(false);
+  });
 });

packages/server/src/shared/messages.ts

@@ -1,5 +1,6 @@
 import { z } from 'zod'
 import { AGENT_LIFECYCLE_STATUSES } from './agent-lifecycle.js'
+import { MAX_EXPLICIT_AGENT_TITLE_CHARS } from '../server/agent/agent-title-limits.js'
 import { AgentProviderSchema } from '../server/agent/provider-manifest.js'
 import type {
   AgentCapabilityFlags,
@@ -89,7 +90,7 @@ const AgentSessionConfigSchema = z.object({
   modeId: z.string().optional(),
   model: z.string().optional(),
   thinkingOptionId: z.string().optional(),
-  title: z.string().trim().min(1).max(40).optional().nullable(),
+  title: z.string().trim().min(1).max(MAX_EXPLICIT_AGENT_TITLE_CHARS).optional().nullable(),
   approvalPolicy: z.string().optional(),
   sandboxMode: z.string().optional(),
   networkAccess: z.boolean().optional(),