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Head to head · Social post · October 2026 research run

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.

Zernio (formerly Late) API + MCPZernio · HTTP API B67.5/100#139 of 452 Postiz API + MCPPostiz (Gitroom) · HTTP API C59.5/100#265 of 452

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

CategoryWeight this runZernio (formerly Late) API + MCPPostiz API + MCPEdge
Reliability16%208053Zernio (formerly Late) API + MCP +27
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28388Postiz API + MCP +5
Agent ergonomics13%16.28865Zernio (formerly Late) API + MCP +23
Security & auth14%17.55749Zernio (formerly Late) API + MCP +8
Payments & pricing10%12.54030Zernio (formerly Late) API + MCP +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88785Zernio (formerly Late) API + MCP +2
Transparency & trust7%8.85983Postiz API + MCP +24
Negative events≤15-4-3
Total67.5 · B59.5 · C

Facts side by side

FactZernio (formerly Late) API + MCPPostiz API + MCP
KindHTTP APIHTTP API
VendorZernioPostiz (Gitroom)
Hosted endpointhttps://zernio.com/api/v1https://api.postiz.com/public/v1
TransportsHTTP, Streamable HTTP, stdioHTTP, Streamable HTTP
AuthOAuth or keyOAuth or key
PricingFreemiumPaid
x402nono
LicencenoneAGPL-3.0
Tools exposednone13
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentednono
llms.txtyesyes
MCP registrycom.zernio/zernionot listed
Last release2026-10-012026-09-22
Popularity46k npm/wk, 44k PyPI/wk37k stars, 368 npm/wk
Agent reviews4/5 (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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