fix: remove identity file persistence — incompatible with concurrent sessions

Multiple sessions in the same directory would collide on the identity
file. In a TCP mesh, state is in-memory so recovering a previous ID
is meaningless — the peer's state is already gone. Each instance gets
a fresh peer ID on startup.

Author: Mearman

README.md

@@ -29,9 +29,9 @@ All state is held in memory and synchronised between peers. Delivery events are
 - On graceful shutdown, coordinator hands over to the longest-running peer
 - On crash, remaining peers race to bind the port (~100ms recovery)
 
-### Identity persistence
+### Identity
 
-Peer IDs are persisted to `~/.agents/identity/{harness}--{cwd}.json` so agents can recover their identity across restarts.
+Each instance gets a unique peer ID on startup. Mesh state is in-memory — when a process exits, its peer is gone. Identity is not persisted because the mesh state dies with the process.
 
 ## Install
 

src/core/mesh-store.ts

@@ -9,9 +9,6 @@
  * Falls back to FileStore if the mesh is unavailable.
  */
 
-import * as fs from "node:fs/promises";
-import * as os from "node:os";
-import * as path from "node:path";
 import * as net from "node:net";
 import { nanoid } from "./nanoid.js";
 import type { CommsStore } from "./comms-store.js";
@@ -137,7 +134,7 @@ export class MeshStore implements CommsStore {
   private messages = new Map<string, RoomMessage[]>();
   private dms = new Map<string, DmMessage[]>();
   private deliveryQueues = new Map<string, DeliveryEvent[]>();
-  private identityDir = path.join(os.homedir(), ".agents", "identity");
+  private identityCache = new Map<string, { id: string }>();
 
   private dataServer: net.Server | undefined;
   private dataPort = 0;
@@ -494,26 +491,13 @@ export class MeshStore implements CommsStore {
     harness: string,
     cwd: string,
   ): Promise<{ id: string } | undefined> {
-    const key = `${harness}--${cwd.replace(/[^a-zA-Z0-9]/g, "_")}`;
-    const filePath = path.join(this.identityDir, `${key}.json`);
-    try {
-      const raw = await fs.readFile(filePath, "utf-8");
-      const parsed: unknown = JSON.parse(raw);
-      if (typeof parsed === "object" && parsed !== null && "id" in parsed) {
-        const id = parsed.id;
-        if (typeof id === "string") return { id };
-      }
-      return undefined;
-    } catch {
-      return undefined;
-    }
+    await Promise.resolve();
+    return this.identityCache.get(`${harness}--${cwd}`);
   }
 
   async writeIdentity(harness: string, cwd: string, id: string): Promise<void> {
-    const key = `${harness}--${cwd.replace(/[^a-zA-Z0-9]/g, "_")}`;
-    const filePath = path.join(this.identityDir, `${key}.json`);
-    await fs.mkdir(this.identityDir, { recursive: true });
-    await fs.writeFile(filePath, JSON.stringify({ id }), "utf-8");
+    await Promise.resolve();
+    this.identityCache.set(`${harness}--${cwd}`, { id });
   }
 
   // -----------------------------------------------------------------------

src/test/mesh-e2e.test.ts

@@ -10,26 +10,12 @@ import { CommsTool } from "../core/tool.js";
 import { buildAction } from "../core/bridge.js";
 import type { DeliveryEvent } from "../core/types.js";
 import * as assert from "node:assert/strict";
-import * as fs from "node:fs/promises";
-import * as path from "node:path";
-import * as os from "node:os";
-
-const TEST_IDENTITY_DIR = path.join(
-  os.homedir(),
-  ".agents",
-  "identity-test-" + String(Date.now()),
-);
 
 async function createStore(
   name: string,
   harness: string,
 ): Promise<{ store: MeshStore; tool: CommsTool; deliveries: DeliveryEvent[] }> {
   const store = new MeshStore();
-  // Override identity dir to avoid polluting real state
-  Object.defineProperty(store, "identityDir", {
-    value: TEST_IDENTITY_DIR,
-    writable: true,
-  });
 
   const deliveries: DeliveryEvent[] = [];
   store.onDelivery = (_agentId: string, event: DeliveryEvent) => {
@@ -163,13 +149,6 @@ async function main(): Promise<void> {
   await a.store.shutdown();
   await b.store.shutdown();
 
-  // Clean up test identity files
-  try {
-    await fs.rm(TEST_IDENTITY_DIR, { recursive: true });
-  } catch {
-    /* ignore */
-  }
-
   console.log("\n✓ All tests passed!");
 }