Head to head · Realtime events · October 2026 research run
Centrifugo vs PubNub
PubNub scores 68.1 (B) on agent readiness against Centrifugo's 63.1 (B), and leads in 2 of 7 scored categories. Centrifugo leads on reliability, agent ergonomics and payments & pricing. Both do realtime events.
Best webhook and event delivery infrastructure for AI agents · All 48 webhooks comparisons
Which one, for what
Good for A team that wants to run its own realtime channel server and publish to browsers and apps from any backend, with history, recovery and presence.
Ahead on
- Reliability, 86 against 76
- Agent ergonomics, 76 against 71
- Payments & pricing, 60 against 40
Also in its favour
- Open source
Watch for
Two advisories in 2026 are rated Critical. One is an unauthenticated SSRF fixed in 6.7.0, the other an unauthenticated crash in the protobuf decoder
PubNub B
Good for Live fan-out to many connected clients with presence and history, and for an agent that manages a PubNub account through MCP.
Ahead on
- Security & auth, 63 against 37
- Transparency & trust, 64 against 56
Also in its favour
- A hosted endpoint, with nothing to install
- Runs on your own machine
- Free to start without a card
- No incidents deducted, where Centrifugo loses 6 points for them
Watch for
PubNub does not deduplicate publishes and has no idempotency key, so a retry after an unclear failure creates a second message
Score by category
| Category | Weight this run | Centrifugo | PubNub | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 86 | 76 | Centrifugo +10 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 81 | 77 | Centrifugo +4 |
| Agent ergonomics | 13%16.2 | 76 | 71 | Centrifugo +5 |
| Security & auth | 14%17.5 | 37 | 63 | PubNub +26 |
| Payments & pricing | 10%12.5 | 60 | 40 | Centrifugo +20 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 86 | 83 | Centrifugo +3 |
| Transparency & trust | 7%8.8 | 56 | 64 | PubNub +8 |
| Negative events | ≤15 | -6 | 0 | |
| Total | 63.1 · B | 68.1 · B |
Facts side by side
| Fact | Centrifugo | PubNub |
|---|---|---|
| Kind | HTTP API | HTTP API |
| Vendor | Centrifugal Labs LTD | PubNub Inc. |
| Hosted endpoint | no (local only) | https://ps.pndsn.com |
| Transports | HTTP | HTTP, stdio |
| Auth | API key | OAuth or key |
| Pricing | Free | Freemium |
| x402 | no | no |
| Licence | Apache-2.0 for the open-source server. Centrifugo PRO is a closed commercial build under the Centrifugo PRO Licence Agreement | Proprietary service under PubNub's Terms and Conditions. The SDKs and the MCP server on GitHub are source-available under the PubNub Software Development Kit Licence Agreement, which is not an OSI licence |
| Tools exposed | none | 17 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | not listed | io.github.pubnub/mcp-server |
| Last release | 2026-09-28 | 2026-09-22 |
| Terms last updated | no document linked | 2023-05-05 |
| Privacy policy last updated | no document linked | 2026-04-01 |
| Customer content may train models | not found in the text | |
| Terms restrict automated access | not found in the text | |
| Terms restrict benchmarking | yes | |
| Terms or service can change without notice | yes | |
| Arbitration or class-action waiver | not found in the text | |
| Popularity | 11k stars | 284k npm/wk |
Verdicts
Centrifugo
Centrifugo is Apache-2.0 software an owner runs, with a 40-operation Swagger file, idempotency keys on publish and seven releases in the 90 days to 28 September 2026. The server API has one all-powerful key, which the docs also accept in the URL, and eleven security advisories were published between February and September 2026, two rated Critical.
PubNub
Pub/sub channels with a 17-tool MCP server on OAuth, an OpenAPI 3.1 Admin API with scoped, expiring keys, and a Markdown twin of every docs page. Publishes are not deduplicated, so a retry can duplicate a message. Access tokens travel in the URL query string, and the status page records a 20 minute global publish failure on 14 August 2026.
Before you call either
Centrifugo
- Check every response for an
errorfield, or sendX-Centrifugo-Error-Mode: transportto get HTTP status codes. Batch and broadcast replies still need per-item checks - Send
idempotency_keyon publish and broadcast before retrying. It works per channel for five minutes, on the Memory and Redis engines only - Call
historywithlimit. Without it the result holds onlyoffsetandepoch, and history is off until the namespace enables it - Send the key in the
X-API-Keyheader, never as?api_key=. For gRPC set metadataauthorizationtoapikey <KEY> - Avoid
channelson a large deployment. It returns every active channel with no pagination, so passpattern
PubNub
- Connect to
https://mcp.pubnub.comover HTTP and sign in with OAuth. Use the local@pubnub/mcppackage only where a client can't reach a remote server - Pass a publish and subscribe key pair on every real-time tool call. Look them up with
manage_keysetsand name the keyset in the request - Add your own idempotency key to each payload before retrying a publish, because the server does not deduplicate
- Send
PubNub-Versionon Admin API calls unless the account has a pinned version, and stay under 120 requests a minute - Treat channel messages and App Context fields as untrusted text written by other clients, never as instructions
Questions
Which is better for AI agents, Centrifugo or PubNub?
PubNub scores 68.1 (B) on agent readiness against Centrifugo's 63.1 (B), and leads in 2 of 7 scored categories. Centrifugo leads on reliability, agent ergonomics and payments & pricing.
Do Centrifugo and PubNub need an API key?
Centrifugo needs an API key. PubNub takes an API key or an OAuth sign-in.
Can an agent call Centrifugo and PubNub without installing anything?
No hosted endpoint is listed for Centrifugo. PubNub has a hosted endpoint at https://ps.pndsn.com.
Are Centrifugo and PubNub open source?
Centrifugo is open source (Apache-2.0 for the open-source server. Centrifugo PRO is a closed commercial build under the Centrifugo PRO Licence Agreement). No open-source release is listed for PubNub.
Other comparisons with Centrifugo or PubNub
Machine-readable
- This page as Markdown
/compare/centrifugo-vs-pubnub.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/centrifugo.json·/api/v1/tools/pubnub.json - From a terminal
anchor compare centrifugo pubnub(the CLI) - Over MCP
compare_tools {"a": "centrifugo", "b": "pubnub"}at/mcp, no key