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Head to head · Social post · October 2026 research run

Zernio (formerly Late) API + MCP vs Publer API + MCP

Zernio (formerly Late) API + MCP has a score of 67.5 (B) against Publer API + MCP's 47.1 (D). Both do social post. The largest gap is maintenance & community, 46 points.

Zernio (formerly Late) API + MCPZernio · HTTP API B67.5/100#139 of 452 Publer API + MCPPubler · HTTP API D47.1/100#388 of 452

Which one, for what

Pick Zernio (formerly Late) API + MCP for

  • reliability (+20)
  • schema & documentation (+37)
  • agent ergonomics (+33)
  • security & auth (+16)
  • payments & pricing (+25)
  • maintenance & community (+46)

Pick Publer API + MCP for

  • transparency & trust (+10)

Score by category

CategoryWeight this runZernio (formerly Late) API + MCPPubler API + MCPEdge
Reliability16%208060Zernio (formerly Late) API + MCP +20
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28346Zernio (formerly Late) API + MCP +37
Agent ergonomics13%16.28855Zernio (formerly Late) API + MCP +33
Security & auth14%17.55741Zernio (formerly Late) API + MCP +16
Payments & pricing10%12.54015Zernio (formerly Late) API + MCP +25
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88741Zernio (formerly Late) API + MCP +46
Transparency & trust7%8.85969Publer API + MCP +10
Negative events≤15-40
Total67.5 · B47.1 · D

Facts side by side

FactZernio (formerly Late) API + MCPPubler API + MCP
KindHTTP APIHTTP API
VendorZernioPubler
Hosted endpointhttps://zernio.com/api/v1https://app.publer.com/api/v1
TransportsHTTP, Streamable HTTP, stdioHTTP
AuthOAuth or keyAPI key
PricingFreemiumPaid
x402nono
Licencenonenone
Tools exposednonenone
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 release2026-10-01none
Popularity46k npm/wk, 44k PyPI/wknone
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.

Publer API + MCP

Scoped API keys (workspaces, accounts, posts, media, analytics) with 401 and 403 errors that name the missing scope or header. API and MCP only on Business and Enterprise, and the free plan has no API.

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

Publer API + MCP

  1. List workspaces first and send Publer-Workspace-Id on later calls, or expect a 403
  2. Poll /job_status/{job_id} after posts/schedule and read payload.failures, since status reads complete even when posts failed
  3. Use the Bearer-API scheme, not Bearer
  4. Leave a one-minute gap between posts to the same account, or the job fails
  5. Read X-RateLimit-Reset after a 429 and wait until then, as there's no Retry-After

Other comparisons with Zernio (formerly Late) API + MCP or Publer API + MCP

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