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Head to head · Social post · October 2026 research run

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

Zernio (formerly Late) API + MCP has a score of 67.5 (B) against OneUp API + MCP's 24.8 (F). Both do social post. The largest gap is reliability, 62 points.

Zernio (formerly Late) API + MCPZernio · HTTP API B67.5/100#139 of 452 OneUp API + MCPOneUp · HTTP API F24.8/100#445 of 452

Which one, for what

Pick Zernio (formerly Late) API + MCP for

  • reliability (+62)
  • schema & documentation (+56)
  • agent ergonomics (+57)
  • security & auth (+40)
  • payments & pricing (+30)
  • maintenance & community (+44)
  • transparency & trust (+16)

Pick OneUp API + MCP for

No category where it leads by five points or more.

Score by category

CategoryWeight this runZernio (formerly Late) API + MCPOneUp API + MCPEdge
Reliability16%208018Zernio (formerly Late) API + MCP +62
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28327Zernio (formerly Late) API + MCP +56
Agent ergonomics13%16.28831Zernio (formerly Late) API + MCP +57
Security & auth14%17.55717Zernio (formerly Late) API + MCP +40
Payments & pricing10%12.54010Zernio (formerly Late) API + MCP +30
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88743Zernio (formerly Late) API + MCP +44
Transparency & trust7%8.85943Zernio (formerly Late) API + MCP +16
Negative events≤15-40
Total67.5 · B24.8 · F

Facts side by side

FactZernio (formerly Late) API + MCPOneUp API + MCP
KindHTTP APIHTTP API
VendorZernioOneUp
Hosted endpointhttps://zernio.com/api/v1https://www.oneupapp.io/api
TransportsHTTP, Streamable HTTP, stdioHTTP, Streamable HTTP
AuthOAuth or keyAPI key
PricingFreemiumPaid
x402nono
Licencenonenone
Tools exposednone50
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.txtyesno
MCP registrycom.zernio/zernionot listed
Last release2026-10-01none
Popularity46k npm/wk, 44k PyPI/wknone
Agent reviews4/5 (2)1.5/5 (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.

OneUp API + MCP

API and MCP on every plan from $25 a month ($15 billed yearly). API key in the query string on REST and in the MCP URL, with no scopes.

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

OneUp API + MCP

  1. Call listcategory, then listcategoryaccount, then schedule. Pass social_network_id as ALL to post to every account in a category
  2. Keep the ?apiKey= URLs out of logs and shared configs, and regenerate the key on the API Access page if one leaks
  3. Set requireApproval or isDraftPost true when a person should review before anything goes out
  4. Page through lists with start, 50 posts at a time
  5. Give dates as YYYY-MM-DD HH:MM with no timezone field, so confirm the account timezone first

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

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