# Zernio (formerly Late) API + MCP vs Postiz API + MCP

> Zernio (formerly Late) API + MCP has a score of 67.5 (B) against Postiz API + MCP's 59.5 (C). Both do social post. The largest gap is reliability, 27 points. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/late-vs-postiz
- Markdown: https://www.anchorterminal.com/compare/late-vs-postiz.md (~1,650 tokens)
- Slim: https://www.anchorterminal.com/compare/late-vs-postiz.min.md (~380 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/late-vs-postiz.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: 2026-10-05

Zernio (formerly Late) API + MCP has a score of 67.5 (B) against Postiz API + MCP's 59.5 (C). Both do social post. The largest gap is reliability, 27 points.

- Zernio (formerly Late) API + MCP: grade B, 67.5/100, rank #139 of 452. Markdown https://www.anchorterminal.com/tools/late.md · JSON https://www.anchorterminal.com/api/v1/tools/late.json
- Postiz API + MCP: grade C, 59.5/100, rank #265 of 452. Markdown https://www.anchorterminal.com/tools/postiz.md · JSON https://www.anchorterminal.com/api/v1/tools/postiz.json

## Which one, for what

Pick Zernio (formerly Late) API + MCP for reliability (+27), agent ergonomics (+23), security & auth (+8), payments & pricing (+10).

Pick Postiz API + MCP for schema & documentation (+5), transparency & trust (+24).

## Score by category

| Category | Weight | Zernio (formerly Late) API + MCP | Postiz API + MCP | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 80 | 53 | Zernio (formerly Late) API + MCP +27 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 83 | 88 | Postiz API + MCP +5 |
| Agent ergonomics | 13% (16.2 this run) | 88 | 65 | Zernio (formerly Late) API + MCP +23 |
| Security & auth | 14% (17.5 this run) | 57 | 49 | Zernio (formerly Late) API + MCP +8 |
| Payments & pricing | 10% (12.5 this run) | 40 | 30 | Zernio (formerly Late) API + MCP +10 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 87 | 85 | Zernio (formerly Late) API + MCP +2 |
| Transparency & trust | 7% (8.8 this run) | 59 | 83 | Postiz API + MCP +24 |
| Negative events | ≤15 | -4 | -3 | |
| **Total** | | **67.5 · B** | **59.5 · C** | |

## Facts side by side

| Fact | Zernio (formerly Late) API + MCP | Postiz API + MCP |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Zernio | Postiz (Gitroom) |
| Hosted endpoint | `https://zernio.com/api/v1` | `https://api.postiz.com/public/v1` |
| Transports | HTTP, Streamable HTTP, stdio | HTTP, Streamable HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Paid |
| x402 | no | no |
| Licence | none | AGPL-3.0 |
| Tools exposed | none | 13 |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | `com.zernio/zernio` | not listed |
| Last release | 2026-10-01 | 2026-09-22 |
| Popularity | 46k npm/wk, 44k PyPI/wk | 37k stars, 368 npm/wk |
| Agent reviews | 4/5 (2) | 3/5 (2) |

## Verdicts

**Zernio (formerly Late) API + MCP.** Idempotency-Key on post creation and other writes, kept 24 hours, with an Idempotent-Replayed header on replays. Several breaking changes shipped between 29 September and 1 October 2026 with no notice period.

**Postiz API + MCP.** AGPL-3.0 and self-hostable with the API and MCP included, 34 platforms. Create-post capped at 90 requests an hour on every Cloud plan.

## Before you call either

### Zernio (formerly Late) API + MCP

1. Send an Idempotency-Key (a fresh UUID per post) on POST /v1/posts and reuse it only on a retry
2. Give timestamps an explicit offset, because times without one now follow the profile timezone rather than UTC
3. Pass accountId when editing or unpublishing a post that targets several accounts
4. Wait Retry-After on 429. Analytics endpoints have their own per-second window
5. Call https://zernio.com/api/v1, not the old getlate.dev base, and pin the SDK version

### Postiz API + MCP

1. Send the key as the `Authorization` header with no `Bearer` prefix on REST calls
2. Batch several posts into one create request to stay under 90 an hour
3. Call integrationSchema (Get Settings) for a channel before scheduling, since each network has its own settings
4. Use the Bearer header on /mcp rather than /mcp/{key} so the key stays out of logs
5. Read output.errors on a failed schedule call and retry with the corrected fields

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