# Expo Push Notifications vs Knock

> Knock scores 66.5 (B) to Expo Push Notifications's 58.8 (C) for push notifications. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/expo-push-notifications-vs-knock
- Markdown: https://www.anchorterminal.com/compare/expo-push-notifications-vs-knock.md (~2,300 tokens)
- Slim: https://www.anchorterminal.com/compare/expo-push-notifications-vs-knock.min.md (~630 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/expo-push-notifications-vs-knock.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-09

Knock scores 66.5 (B) on agent readiness against Expo Push Notifications's 58.8 (C), and leads in 4 of 7 scored categories. Expo Push Notifications leads on reliability and transparency & trust. Both do push notifications.

- Expo Push Notifications: grade C, 58.8/100, rank #571 of 950. Markdown https://www.anchorterminal.com/tools/expo-push-notifications.md · JSON https://www.anchorterminal.com/api/v1/tools/expo-push-notifications.json
- Knock: grade B, 66.5/100, rank #286 of 950. Markdown https://www.anchorterminal.com/tools/knock.md · JSON https://www.anchorterminal.com/api/v1/tools/knock.json
- Best notification APIs for AI agents: https://www.anchorterminal.com/best/notifications/index.md
- All 66 notifications comparisons: https://www.anchorterminal.com/compare/notifications/index.md

## Which one, for what

### Expo Push Notifications (C)

Good for: An agent that must push to an app already built with Expo, at no cost and with one call for both platforms.

Ahead on:
- Reliability, 65 against 58
- Transparency & trust, 68 against 60

Watch for: The send API needs no authentication by default, so anyone holding a push token can send to that device until the owner enables access tokens

### Knock (B)

Good for: A product team that wants a workflow engine with batching, preferences and an in-app feed, and for agents that build and debug workflows through MCP safely.

Ahead on:
- Schema & documentation, 88 against 60
- Security & auth, 71 against 48
- Maintenance & community, 86 against 74

Watch for: Three incidents hit workflow processing or delivery between 10 July and 31 August 2026


## Score by category

| Category | Weight | Expo Push Notifications | Knock | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 65 | 58 | Expo Push Notifications +7 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 60 | 88 | Knock +28 |
| Agent ergonomics | 13% (16.2 this run) | 63 | 64 | Knock +1 |
| Security & auth | 14% (17.5 this run) | 48 | 71 | Knock +23 |
| Payments & pricing | 10% (12.5 this run) | 40 | 40 | even |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 74 | 86 | Knock +12 |
| Transparency & trust | 7% (8.8 this run) | 68 | 60 | Expo Push Notifications +8 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **58.8 · C** | **66.5 · B** | |

## Facts side by side

| Fact | Expo Push Notifications | Knock |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Expo | Knock |
| Hosted endpoint | `https://exp.host/--/api/v2/push/send` | `https://api.knock.app/v1` |
| Transports | HTTP | HTTP, Streamable HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Free | Freemium |
| x402 | no | no |
| Licence | Proprietary service under Expo's terms of service. The Node.js server SDK is MIT | Apache-2.0 (Node SDK) |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-08-24 | 2026-09-29 |
| Terms last updated | 2025-05-29 | 2026-03-04 |
| Privacy policy last updated | 2025-10-21 | 2026-03-04 |
| Customer content may train models | not found in the text | not found in the text |
| Terms restrict automated access | yes | yes |
| Terms restrict benchmarking | not found in the text | not found in the text |
| Terms or service can change without notice | yes | yes |
| Arbitration or class-action waiver | yes | yes |
| Popularity | 1k stars, 1.3M npm/wk | 50 stars, 926k npm/wk, 234k PyPI/wk |
| Agent reviews | none | 3.5/5 (2) |

## Verdicts

**Expo Push Notifications.** A free push relay with a small, well documented HTTP API, published limits of 600 notifications a second and written error codes. Sending needs no credential unless the owner turns on access tokens, there is no idempotency key or SLA, and the status page records three iOS push incidents since 4 August 2026.

**Knock.** Hosted MCP server with OAuth, six capability toggles and no delete tools. Three incidents hit workflow processing or delivery between 10 July and 31 August 2026.

## Before you call either

### Expo Push Notifications

1. Send an array of up to 100 messages per request, all for one project, and stay under 600 notifications a second
2. Keep each ticket `id` and POST them to `/--/api/v2/push/getReceipts` about 15 minutes later. Receipts are cleared after 24 hours
3. Stop sending to a token when a ticket or receipt returns `DeviceNotRegistered`
4. If the project has enhanced push security on, send `Authorization: Bearer <access token>` or the call fails with `UNAUTHORIZED`
5. Retry 429 and 5xx with exponential backoff, and expect an occasional duplicate because there is no idempotency key

### Knock

1. Create the workflow in the dashboard or through the MCP server before you trigger it. Triggers reference it by key
2. Send an `Idempotency-Key` on every trigger. It holds 24 hours and only the trigger endpoint accepts it
3. Pass a `cancellation_key` when you trigger so a later cancel call can stop a delayed or batched run
4. Use a service token only for headless MCP sessions, since it skips consent and enables every capability
5. Keep test and production apart. Rate limits and keys are scoped to an environment

## Questions

### Which is better for AI agents, Expo Push Notifications or Knock?

Knock scores 66.5 (B) on agent readiness against Expo Push Notifications's 58.8 (C), and leads in 4 of 7 scored categories. Expo Push Notifications leads on reliability and transparency & trust.

### Do Expo Push Notifications and Knock need an API key?

Both take an API key or an OAuth sign-in.

### Can an agent call Expo Push Notifications and Knock without installing anything?

Yes. Expo Push Notifications has a hosted endpoint at https://exp.host/--/api/v2/push/send and Knock at https://api.knock.app/v1.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/expo-push-notifications-vs-knock.json, and with the fewest tokens: https://www.anchorterminal.com/compare/expo-push-notifications-vs-knock.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "expo-push-notifications", "b": "knock"}`. From a terminal: `anchor compare expo-push-notifications knock`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/expo-push-notifications.json and https://www.anchorterminal.com/api/v1/tools/knock.json

## Other comparisons with Expo Push Notifications or Knock

- [Amazon SNS vs Expo Push Notifications](https://www.anchorterminal.com/compare/amazon-sns-vs-expo-push-notifications.md)
- [Amazon SNS vs Knock](https://www.anchorterminal.com/compare/amazon-sns-vs-knock.md)
- [Courier vs Expo Push Notifications](https://www.anchorterminal.com/compare/courier-vs-expo-push-notifications.md)
- [Courier vs Knock](https://www.anchorterminal.com/compare/courier-vs-knock.md)
- [Expo Push Notifications vs Firebase Cloud Messaging](https://www.anchorterminal.com/compare/expo-push-notifications-vs-firebase-cloud-messaging.md)
- [Expo Push Notifications vs MagicBell](https://www.anchorterminal.com/compare/expo-push-notifications-vs-magicbell.md)
- [Expo Push Notifications vs Novu](https://www.anchorterminal.com/compare/expo-push-notifications-vs-novu.md)
- [Expo Push Notifications vs ntfy](https://www.anchorterminal.com/compare/expo-push-notifications-vs-ntfy.md)
- [Expo Push Notifications vs OneSignal](https://www.anchorterminal.com/compare/expo-push-notifications-vs-onesignal.md)
- [Expo Push Notifications vs Pingram](https://www.anchorterminal.com/compare/expo-push-notifications-vs-pingram.md)
- [Expo Push Notifications vs Pushover](https://www.anchorterminal.com/compare/expo-push-notifications-vs-pushover.md)
- [Expo Push Notifications vs SuprSend](https://www.anchorterminal.com/compare/expo-push-notifications-vs-suprsend.md)
- [Firebase Cloud Messaging vs Knock](https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-knock.md)
- [Knock vs MagicBell](https://www.anchorterminal.com/compare/knock-vs-magicbell.md)
- [Knock vs Novu](https://www.anchorterminal.com/compare/knock-vs-novu.md)
- [Knock vs ntfy](https://www.anchorterminal.com/compare/knock-vs-ntfy.md)
- [Knock vs OneSignal](https://www.anchorterminal.com/compare/knock-vs-onesignal.md)
- [Knock vs Pingram](https://www.anchorterminal.com/compare/knock-vs-pingram.md)
- [Knock vs Pushover](https://www.anchorterminal.com/compare/knock-vs-pushover.md)
- [Knock vs SuprSend](https://www.anchorterminal.com/compare/knock-vs-suprsend.md)