diff --git a/src/lib/account-types.test.ts b/src/lib/account-types.test.ts
new file mode 100644
index 0000000..e48a9af
--- /dev/null
+++ b/src/lib/account-types.test.ts
@@ -0,0 +1,202 @@
+import { describe, it, expect, vi } from "vitest";
+import { ReadOnlyAccount } from "./account-types";
+import * as nip05 from "./nip05";
+
+// Mock the NIP-05 resolver
+vi.mock("./nip05", () => ({
+  resolveNip05: vi.fn(),
+}));
+
+describe("ReadOnlyAccount", () => {
+  describe("fromHex", () => {
+    it("should create account from valid hex pubkey", () => {
+      const hex =
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+      const account = ReadOnlyAccount.fromHex(hex);
+
+      expect(account.pubkey).toBe(hex);
+      expect(account.id).toBe(`readonly:${hex}`);
+      expect(account.metadata.type).toBe("readonly");
+      expect(account.metadata.source).toBe("hex");
+      expect(account.metadata.originalInput).toBe(hex);
+      expect(account.signer).toBeUndefined();
+    });
+
+    it("should normalize hex to lowercase", () => {
+      const hex =
+        "3BF0C63FCB93463407AF97A5E5EE64FA883D107EF9E558472C4EB9AAAEFA459D";
+      const account = ReadOnlyAccount.fromHex(hex);
+
+      expect(account.pubkey).toBe(hex.toLowerCase());
+    });
+
+    it("should reject invalid hex length", () => {
+      expect(() => ReadOnlyAccount.fromHex("abc123")).toThrow(
+        "Invalid hex pubkey",
+      );
+    });
+
+    it("should reject non-hex characters", () => {
+      const invalidHex =
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa45zz";
+      expect(() => ReadOnlyAccount.fromHex(invalidHex)).toThrow(
+        "Invalid hex pubkey",
+      );
+    });
+  });
+
+  describe("fromNpub", () => {
+    it("should create account from valid npub", async () => {
+      const npub =
+        "npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6";
+      const account = await ReadOnlyAccount.fromNpub(npub);
+
+      expect(account.pubkey).toBe(
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d",
+      );
+      expect(account.metadata.source).toBe("npub");
+      expect(account.metadata.originalInput).toBe(npub);
+    });
+
+    it("should reject invalid npub format", async () => {
+      await expect(ReadOnlyAccount.fromNpub("invalid")).rejects.toThrow(
+        "Failed to decode npub",
+      );
+    });
+
+    it("should reject non-npub nip19 formats", async () => {
+      const nsec =
+        "nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5";
+      await expect(ReadOnlyAccount.fromNpub(nsec)).rejects.toThrow(
+        "Invalid npub: expected npub format",
+      );
+    });
+  });
+
+  describe("fromNprofile", () => {
+    it("should create account from valid nprofile", async () => {
+      const nprofile =
+        "nprofile1qqsrhuxx8l9ex335q7he0f09aej04zpazpl0ne2cgukyawd24mayt8gpp4mhxue69uhhytnc9e3k7mgpz4mhxue69uhkg6nzv9ejuumpv34kytnrdaksjlyr9p";
+      const account = await ReadOnlyAccount.fromNprofile(nprofile);
+
+      expect(account.pubkey).toBe(
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d",
+      );
+      expect(account.metadata.source).toBe("nprofile");
+      expect(account.metadata.relays).toBeDefined();
+      expect(account.metadata.relays?.length).toBeGreaterThan(0);
+    });
+
+    it("should reject invalid nprofile format", async () => {
+      await expect(ReadOnlyAccount.fromNprofile("invalid")).rejects.toThrow(
+        "Failed to decode nprofile",
+      );
+    });
+
+    it("should reject non-nprofile nip19 formats", async () => {
+      const npub =
+        "npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6";
+      await expect(ReadOnlyAccount.fromNprofile(npub)).rejects.toThrow(
+        "Invalid nprofile: expected nprofile format",
+      );
+    });
+  });
+
+  describe("fromNip05", () => {
+    it("should create account from valid nip-05", async () => {
+      const nip05Id = "alice@example.com";
+      const pubkey =
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+
+      vi.mocked(nip05.resolveNip05).mockResolvedValue(pubkey);
+
+      const account = await ReadOnlyAccount.fromNip05(nip05Id);
+
+      expect(account.pubkey).toBe(pubkey);
+      expect(account.metadata.source).toBe("nip05");
+      expect(account.metadata.nip05).toBe(nip05Id);
+      expect(account.metadata.originalInput).toBe(nip05Id);
+      expect(nip05.resolveNip05).toHaveBeenCalledWith(nip05Id);
+    });
+
+    it("should reject when nip-05 resolution fails", async () => {
+      vi.mocked(nip05.resolveNip05).mockResolvedValue(null);
+
+      await expect(ReadOnlyAccount.fromNip05("invalid@example.com")).rejects.toThrow(
+        "Failed to resolve NIP-05 identifier",
+      );
+    });
+  });
+
+  describe("toJSON and fromJSON", () => {
+    it("should serialize and deserialize correctly", () => {
+      const hex =
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+      const account = ReadOnlyAccount.fromHex(hex);
+
+      const json = account.toJSON();
+      const restored = ReadOnlyAccount.fromJSON(json);
+
+      expect(restored.pubkey).toBe(account.pubkey);
+      expect(restored.id).toBe(account.id);
+      expect(restored.metadata.type).toBe(account.metadata.type);
+      expect(restored.metadata.source).toBe(account.metadata.source);
+      expect(restored.metadata.originalInput).toBe(
+        account.metadata.originalInput,
+      );
+    });
+
+    it("should preserve nprofile relays through serialization", async () => {
+      const nprofile =
+        "nprofile1qqsrhuxx8l9ex335q7he0f09aej04zpazpl0ne2cgukyawd24mayt8gpp4mhxue69uhhytnc9e3k7mgpz4mhxue69uhkg6nzv9ejuumpv34kytnrdaksjlyr9p";
+      const account = await ReadOnlyAccount.fromNprofile(nprofile);
+
+      const json = account.toJSON();
+      const restored = ReadOnlyAccount.fromJSON(json);
+
+      expect(restored.metadata.relays).toEqual(account.metadata.relays);
+    });
+
+    it("should preserve nip05 identifier through serialization", async () => {
+      const nip05Id = "alice@example.com";
+      const pubkey =
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+
+      vi.mocked(nip05.resolveNip05).mockResolvedValue(pubkey);
+
+      const account = await ReadOnlyAccount.fromNip05(nip05Id);
+
+      const json = account.toJSON();
+      const restored = ReadOnlyAccount.fromJSON(json);
+
+      expect(restored.metadata.nip05).toBe(nip05Id);
+    });
+  });
+
+  describe("account properties", () => {
+    it("should have no signer for read-only accounts", () => {
+      const hex =
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+      const account = ReadOnlyAccount.fromHex(hex);
+
+      expect(account.signer).toBeUndefined();
+    });
+
+    it("should have consistent ID format", () => {
+      const hex =
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+      const account = ReadOnlyAccount.fromHex(hex);
+
+      expect(account.id).toBe(`readonly:${hex}`);
+      expect(account.id).toContain("readonly:");
+    });
+
+    it("should have readonly type in metadata", () => {
+      const hex =
+        "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+      const account = ReadOnlyAccount.fromHex(hex);
+
+      expect(account.metadata.type).toBe("readonly");
+    });
+  });
+});
diff --git a/src/lib/account-types.ts b/src/lib/account-types.ts
new file mode 100644
index 0000000..e406888
--- /dev/null
+++ b/src/lib/account-types.ts
@@ -0,0 +1,129 @@
+import { nip19 } from "nostr-tools";
+import { resolveNip05 } from "@/lib/nip05";
+
+/**
+ * Account interface matching applesauce-accounts
+ */
+export interface Account {
+  id: string;
+  pubkey: string;
+  signer?: any;
+  metadata?: Record<string, any>;
+  toJSON(): any;
+}
+
+/**
+ * Read-only account - no signing capability
+ * Supports login via npub, nip-05, hex pubkey, or nprofile
+ */
+export class ReadOnlyAccount implements Account {
+  id: string;
+  pubkey: string;
+  signer = undefined;
+  metadata: {
+    type: "readonly";
+    source: "npub" | "nip05" | "hex" | "nprofile";
+    originalInput: string;
+    relays?: string[]; // from nprofile
+    nip05?: string; // original nip-05 identifier
+  };
+
+  constructor(
+    pubkey: string,
+    source: "npub" | "nip05" | "hex" | "nprofile",
+    metadata: Partial<ReadOnlyAccount["metadata"]>,
+  ) {
+    this.pubkey = pubkey;
+    this.id = `readonly:${pubkey}`;
+    this.metadata = {
+      type: "readonly",
+      source,
+      originalInput: metadata.originalInput || pubkey,
+      ...metadata,
+    };
+  }
+
+  toJSON() {
+    return {
+      id: this.id,
+      pubkey: this.pubkey,
+      metadata: this.metadata,
+    };
+  }
+
+  static fromJSON(data: any): ReadOnlyAccount {
+    return new ReadOnlyAccount(data.pubkey, data.metadata.source, {
+      originalInput: data.metadata.originalInput,
+      relays: data.metadata.relays,
+      nip05: data.metadata.nip05,
+    });
+  }
+
+  /**
+   * Create account from npub (NIP-19 encoded public key)
+   */
+  static async fromNpub(npub: string): Promise<ReadOnlyAccount> {
+    try {
+      const decoded = nip19.decode(npub);
+      if (decoded.type !== "npub") {
+        throw new Error("Invalid npub: expected npub format");
+      }
+      return new ReadOnlyAccount(decoded.data, "npub", {
+        originalInput: npub,
+      });
+    } catch (error) {
+      throw new Error(
+        `Failed to decode npub: ${error instanceof Error ? error.message : "Unknown error"}`,
+      );
+    }
+  }
+
+  /**
+   * Create account from NIP-05 identifier (user@domain.com)
+   */
+  static async fromNip05(nip05: string): Promise<ReadOnlyAccount> {
+    const pubkey = await resolveNip05(nip05);
+    if (!pubkey) {
+      throw new Error(`Failed to resolve NIP-05 identifier: ${nip05}`);
+    }
+    return new ReadOnlyAccount(pubkey, "nip05", {
+      originalInput: nip05,
+      nip05,
+    });
+  }
+
+  /**
+   * Create account from nprofile (NIP-19 encoded profile with relay hints)
+   */
+  static async fromNprofile(nprofile: string): Promise<ReadOnlyAccount> {
+    try {
+      const decoded = nip19.decode(nprofile);
+      if (decoded.type !== "nprofile") {
+        throw new Error("Invalid nprofile: expected nprofile format");
+      }
+      return new ReadOnlyAccount(decoded.data.pubkey, "nprofile", {
+        originalInput: nprofile,
+        relays: decoded.data.relays,
+      });
+    } catch (error) {
+      throw new Error(
+        `Failed to decode nprofile: ${error instanceof Error ? error.message : "Unknown error"}`,
+      );
+    }
+  }
+
+  /**
+   * Create account from hex public key
+   */
+  static fromHex(hex: string): ReadOnlyAccount {
+    // Validate hex format (64 character hex string)
+    if (!/^[0-9a-f]{64}$/i.test(hex)) {
+      throw new Error(
+        "Invalid hex pubkey: expected 64 character hexadecimal string",
+      );
+    }
+    return new ReadOnlyAccount(hex.toLowerCase(), "hex", {
+      originalInput: hex,
+    });
+  }
+}
diff --git a/src/lib/login-parser.test.ts b/src/lib/login-parser.test.ts
new file mode 100644
index 0000000..f5444a9
--- /dev/null
+++ b/src/lib/login-parser.test.ts
@@ -0,0 +1,214 @@
+import { describe, it, expect, vi } from "vitest";
+import {
+  detectLoginInputType,
+  createAccountFromInput,
+  isValidLoginInput,
+} from "./login-parser";
+import * as nip05 from "./nip05";
+
+// Mock the NIP-05 module
+vi.mock("./nip05", () => ({
+  resolveNip05: vi.fn(),
+  isNip05: vi.fn((value: string) => {
+    // Simple mock implementation
+    return /^[a-zA-Z0-9._-]+@[a-zA-Z0-9][\w.-]+\.[a-zA-Z]{2,}$/.test(value);
+  }),
+}));
+
+describe("detectLoginInputType", () => {
+  it("should detect npub format", () => {
+    const npub =
+      "npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6";
+    expect(detectLoginInputType(npub)).toBe("npub");
+  });
+
+  it("should detect nprofile format", () => {
+    const nprofile =
+      "nprofile1qqsrhuxx8l9ex335q7he0f09aej04zpazpl0ne2cgukyawd24mayt8gpp4mhxue69uhhytnc9e3k7mgpz4mhxue69uhkg6nzv9ejuumpv34kytnrdaksjlyr9p";
+    expect(detectLoginInputType(nprofile)).toBe("nprofile");
+  });
+
+  it("should detect hex pubkey format", () => {
+    const hex =
+      "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+    expect(detectLoginInputType(hex)).toBe("hex");
+  });
+
+  it("should detect nip-05 format", () => {
+    expect(detectLoginInputType("alice@example.com")).toBe("nip05");
+    expect(detectLoginInputType("bob@nostr.com")).toBe("nip05");
+  });
+
+  it("should detect bunker URL format", () => {
+    expect(detectLoginInputType("bunker://pubkey?relay=wss://...")).toBe(
+      "bunker",
+    );
+    expect(
+      detectLoginInputType("nostrconnect://pubkey?relay=wss://..."),
+    ).toBe("bunker");
+  });
+
+  it("should return extension for empty input", () => {
+    expect(detectLoginInputType("")).toBe("extension");
+    expect(detectLoginInputType("   ")).toBe("extension");
+  });
+
+  it("should return unknown for invalid input", () => {
+    expect(detectLoginInputType("invalid")).toBe("unknown");
+    expect(detectLoginInputType("random text")).toBe("unknown");
+  });
+
+  it("should handle whitespace correctly", () => {
+    const npub =
+      "  npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6  ";
+    expect(detectLoginInputType(npub)).toBe("npub");
+  });
+
+  it("should detect hex with uppercase", () => {
+    const hex =
+      "3BF0C63FCB93463407AF97A5E5EE64FA883D107EF9E558472C4EB9AAAEFA459D";
+    expect(detectLoginInputType(hex)).toBe("hex");
+  });
+
+  it("should reject too short hex", () => {
+    expect(detectLoginInputType("3bf0c63f")).toBe("unknown");
+  });
+
+  it("should reject too long hex", () => {
+    const longHex =
+      "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d00";
+    expect(detectLoginInputType(longHex)).toBe("unknown");
+  });
+});
+
+describe("createAccountFromInput", () => {
+  it("should create account from npub", async () => {
+    const npub =
+      "npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6";
+    const account = await createAccountFromInput(npub);
+
+    expect(account.pubkey).toBe(
+      "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d",
+    );
+    expect(account.metadata.source).toBe("npub");
+  });
+
+  it("should create account from hex", async () => {
+    const hex =
+      "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+    const account = await createAccountFromInput(hex);
+
+    expect(account.pubkey).toBe(hex);
+    expect(account.metadata.source).toBe("hex");
+  });
+
+  it("should create account from nprofile", async () => {
+    const nprofile =
+      "nprofile1qqsrhuxx8l9ex335q7he0f09aej04zpazpl0ne2cgukyawd24mayt8gpp4mhxue69uhhytnc9e3k7mgpz4mhxue69uhkg6nzv9ejuumpv34kytnrdaksjlyr9p";
+    const account = await createAccountFromInput(nprofile);
+
+    expect(account.pubkey).toBe(
+      "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d",
+    );
+    expect(account.metadata.source).toBe("nprofile");
+    expect(account.metadata.relays).toBeDefined();
+  });
+
+  it("should create account from nip-05", async () => {
+    const nip05Id = "alice@example.com";
+    const pubkey =
+      "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+
+    vi.mocked(nip05.resolveNip05).mockResolvedValue(pubkey);
+
+    const account = await createAccountFromInput(nip05Id);
+
+    expect(account.pubkey).toBe(pubkey);
+    expect(account.metadata.source).toBe("nip05");
+    expect(account.metadata.nip05).toBe(nip05Id);
+  });
+
+  it("should throw error for bunker URL (not yet implemented)", async () => {
+    const bunker = "bunker://pubkey?relay=wss://relay.example.com";
+
+    await expect(createAccountFromInput(bunker)).rejects.toThrow(
+      "Remote signer (NIP-46) support coming soon",
+    );
+  });
+
+  it("should throw error for extension (requires UI)", async () => {
+    await expect(createAccountFromInput("")).rejects.toThrow(
+      "Extension login requires UI interaction",
+    );
+  });
+
+  it("should throw error for unknown format", async () => {
+    await expect(createAccountFromInput("invalid")).rejects.toThrow(
+      "Unknown input format",
+    );
+  });
+
+  it("should handle whitespace in input", async () => {
+    const hex =
+      "  3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d  ";
+    const account = await createAccountFromInput(hex);
+
+    expect(account.pubkey).toBe(hex.trim().toLowerCase());
+  });
+
+  it("should throw descriptive error for invalid npub", async () => {
+    await expect(createAccountFromInput("npub1invalid")).rejects.toThrow(
+      "Failed to decode npub",
+    );
+  });
+
+  it("should throw descriptive error for failed nip-05 resolution", async () => {
+    vi.mocked(nip05.resolveNip05).mockResolvedValue(null);
+
+    await expect(createAccountFromInput("notfound@example.com")).rejects.toThrow(
+      "Failed to resolve NIP-05 identifier",
+    );
+  });
+});
+
+describe("isValidLoginInput", () => {
+  it("should return true for valid npub", () => {
+    const npub =
+      "npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6";
+    expect(isValidLoginInput(npub)).toBe(true);
+  });
+
+  it("should return true for valid hex", () => {
+    const hex =
+      "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+    expect(isValidLoginInput(hex)).toBe(true);
+  });
+
+  it("should return true for valid nip-05", () => {
+    expect(isValidLoginInput("alice@example.com")).toBe(true);
+  });
+
+  it("should return true for valid nprofile", () => {
+    const nprofile =
+      "nprofile1qqsrhuxx8l9ex335q7he0f09aej04zpazpl0ne2cgukyawd24mayt8gpp4mhxue69uhhytnc9e3k7mgpz4mhxue69uhkg6nzv9ejuumpv34kytnrdaksjlyr9p";
+    expect(isValidLoginInput(nprofile)).toBe(true);
+  });
+
+  it("should return true for bunker URL", () => {
+    expect(isValidLoginInput("bunker://pubkey?relay=wss://...")).toBe(true);
+  });
+
+  it("should return false for empty input", () => {
+    expect(isValidLoginInput("")).toBe(false);
+    expect(isValidLoginInput("   ")).toBe(false);
+  });
+
+  it("should return false for unknown format", () => {
+    expect(isValidLoginInput("invalid")).toBe(false);
+  });
+
+  it("should return false for extension (requires UI)", () => {
+    // Empty string triggers extension type
+    expect(isValidLoginInput("")).toBe(false);
+  });
+});
diff --git a/src/lib/login-parser.ts b/src/lib/login-parser.ts
new file mode 100644
index 0000000..06ebebf
--- /dev/null
+++ b/src/lib/login-parser.ts
@@ -0,0 +1,100 @@
+import { isNip05 } from "@/lib/nip05";
+import { ReadOnlyAccount } from "@/lib/account-types";
+
+/**
+ * Types of login input formats supported
+ */
+export type LoginInputType =
+  | "npub"
+  | "nprofile"
+  | "nip05"
+  | "hex"
+  | "bunker"
+  | "extension"
+  | "unknown";
+
+/**
+ * Detect the type of login input
+ * @param input - The user's login input string
+ * @returns The detected input type
+ */
+export function detectLoginInputType(input: string): LoginInputType {
+  if (!input || input.trim() === "") {
+    return "extension"; // Default to extension when no input
+  }
+
+  const trimmed = input.trim();
+
+  // NIP-19 encoded formats
+  if (trimmed.startsWith("npub1")) return "npub";
+  if (trimmed.startsWith("nprofile1")) return "nprofile";
+
+  // Bunker/Nostr Connect URLs (NIP-46)
+  if (trimmed.startsWith("bunker://")) return "bunker";
+  if (trimmed.startsWith("nostrconnect://")) return "bunker";
+
+  // NIP-05 identifier (user@domain.com or domain.com)
+  if (isNip05(trimmed)) return "nip05";
+
+  // Hex pubkey (64 character hex string)
+  if (/^[0-9a-f]{64}$/i.test(trimmed)) return "hex";
+
+  return "unknown";
+}
+
+/**
+ * Create an account from login input
+ * @param input - The user's login input string
+ * @returns A promise that resolves to an Account
+ * @throws Error if the input format is invalid or account creation fails
+ */
+export async function createAccountFromInput(
+  input: string,
+): Promise<ReadOnlyAccount> {
+  const trimmed = input.trim();
+  const type = detectLoginInputType(trimmed);
+
+  switch (type) {
+    case "npub":
+      return await ReadOnlyAccount.fromNpub(trimmed);
+
+    case "nprofile":
+      return await ReadOnlyAccount.fromNprofile(trimmed);
+
+    case "nip05":
+      return await ReadOnlyAccount.fromNip05(trimmed);
+
+    case "hex":
+      return ReadOnlyAccount.fromHex(trimmed);
+
+    case "bunker":
+      throw new Error(
+        "Remote signer (NIP-46) support coming soon. Currently supports read-only accounts only.",
+      );
+
+    case "extension":
+      throw new Error(
+        "Extension login requires UI interaction. Please use the login dialog.",
+      );
+
+    case "unknown":
+    default:
+      throw new Error(
+        `Unknown input format. Supported formats: npub, nprofile, hex pubkey, NIP-05 (user@domain.com)`,
+      );
+  }
+}
+
+/**
+ * Validate if an input string is a valid login format
+ * @param input - The input to validate
+ * @returns True if the input is a valid format
+ */
+export function isValidLoginInput(input: string): boolean {
+  if (!input || input.trim() === "") {
+    return false; // Empty input is invalid for this check
+  }
+
+  const type = detectLoginInputType(input);
+  return type !== "unknown" && type !== "extension";
+}