Requested Changes

1. Fix the two known bugs instead of testing for them

getAll() and search() crash when called without options because of options! on mem0.ts:313 and mem0.ts:364. Change options! to (options ?? {}) in both places. Then write tests that assert the correct behavior (no crash), not the current broken behavior.

2. Remove tautological tests

~60% of the unit tests mock fetch to return X, call a client method, then assert the result is X. Since most methods (get, history, users, search, getAll, feedback, getWebhooks) return response.json() unchanged, these assertions test the mock, not the client.

Delete tests that assert response field values or typeof checks against mock data. Replace them with tests that verify what the client actually does: request URL construction, HTTP method, payload transformation (org/project attachment, memoryId -> memory_id, api_version -> version, v1 GET-with-params vs v2 POST-with-body routing, conditional field inclusion in update(), entity type routing in deleteUsers()).

3. Break memoryClient.unit.test.ts into multiple files

1750 lines in a single test file is too large. Split by concern:

• memoryClient.init.test.ts — constructor, validation, ping
• memoryClient.crud.test.ts — add, get, getAll, update, delete, deleteAll
• memoryClient.search.test.ts — search (v1/v2 routing, filters)
• memoryClient.batch.test.ts — batchUpdate, batchDelete
• memoryClient.users.test.ts — users, deleteUser, deleteUsers
• memoryClient.webhooks.test.ts — getWebhooks, createWebhook, updateWebhook, deleteWebhook
• memoryClient.project.test.ts — getProject, updateProject, exports, feedback

The helpers and mock setup can stay in helpers.ts.

4. Replace any with SDK types

Every let result: any / let memory: any should use the actual types from mem0.types (Memory, AllUsers, MemoryHistory, etc.). This is a TypeScript SDK — the tests should catch type regressions at compile time.

5. Fix the mock fetch URL matching

String.includes() means /v1/memories/ also matches /v1/memories/search/. Sort patterns longest-first before matching so more specific routes win regardless of insertion order.

6. Don't ship dead code to main

The exception hierarchy (289 lines, 14 classes) is not integrated into the client. Either wire it into _fetchWithErrorHandling in this PR or keep it on the feature branch until it's ready.

7. Revert the version bump

2.4.1 -> 2.4.2 for a PR with no user-facing changes violates SemVer. Bump the version when the exceptions are actually integrated.

8. Fix the deleteUsers test setup bug

In the deleteUsers describe block, createClientWithMockedAxios() is called twice — the first call's mock is immediately discarded. Use a single call.

9. Fix the OSS LLM mock

The llmCallCount % 2 alternating pattern couples tests to internal call order. Mock based on prompt content or use mockResolvedValueOnce() per test so changes to the internal call sequence don't silently break everything.

10. Preserve the original E2E tests

The original memoryClient.test.ts had real integration tests. Move them to memoryClient.e2e.test.ts with a skip-by-default flag instead of replacing them entirely with mocks.

11. Remove the changelog entry