Get an audit

Head to head · Social post · October 2026 research run

Zernio (formerly Late) API + MCP vs Upload-Post API + MCP

Zernio (formerly Late) API + MCP has a score of 67.5 (B) against Upload-Post API + MCP's 58.9 (C). Both do social post. The largest gap is security & auth, 25 points.

Zernio (formerly Late) API + MCPZernio · HTTP API B67.5/100#139 of 452 Upload-Post API + MCPUpload-Post · HTTP API C58.9/100#275 of 452

Which one, for what

Pick Zernio (formerly Late) API + MCP for

  • reliability (+23)
  • agent ergonomics (+16)
  • security & auth (+25)
  • payments & pricing (+10)
  • maintenance & community (+8)

Pick Upload-Post API + MCP for

  • transparency & trust (+14)

Score by category

CategoryWeight this runZernio (formerly Late) API + MCPUpload-Post API + MCPEdge
Reliability16%208057Zernio (formerly Late) API + MCP +23
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28381Zernio (formerly Late) API + MCP +2
Agent ergonomics13%16.28872Zernio (formerly Late) API + MCP +16
Security & auth14%17.55732Zernio (formerly Late) API + MCP +25
Payments & pricing10%12.54030Zernio (formerly Late) API + MCP +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88779Zernio (formerly Late) API + MCP +8
Transparency & trust7%8.85973Upload-Post API + MCP +14
Negative events≤15-40
Total67.5 · B58.9 · C

Facts side by side

FactZernio (formerly Late) API + MCPUpload-Post API + MCP
KindHTTP APIHTTP API
VendorZernioUpload-Post
Hosted endpointhttps://zernio.com/api/v1https://api.upload-post.com/api
TransportsHTTP, Streamable HTTP, stdioHTTP, Streamable HTTP, stdio
AuthOAuth or keyOAuth or key
PricingFreemiumFreemium
x402nono
LicencenoneMIT
Tools exposednone59
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/zerniocom.upload-post/mcp
Last release2026-10-012026-09-27
Popularity46k npm/wk, 44k PyPI/wk8 stars, 1.9k npm/wk, 6.2k PyPI/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.

Upload-Post API + MCP

Free plan with 2 profiles and 10 uploads a month, no card. One account key with no scopes, and the MCP's OAuth grants a single mcp.full scope.

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

Upload-Post API + MCP

  1. Send Authorization: Apikey <key> on REST. The MCP also takes Bearer
  2. Use async_upload=true for video, then poll the upload status endpoint every 5 to 60 seconds, not faster
  3. Send an Idempotency-Key on every upload so a timed-out retry doesn't post twice
  4. Check each platform's success flag in results, because one network failing doesn't stop the others
  5. Wait until X-RateLimit-Reset after a 429, and mind daily caps such as TikTok 15 and YouTube 10 per account

Other comparisons with Zernio (formerly Late) API + MCP or Upload-Post API + MCP

Machine-readable

For companies

Do agents find, use and choose your tools?

An agent-readiness audit runs our probes, task suite and eight reviewer agents against your public and internal tools, and comes back with a scorecard, the transcripts of what failed, and a fix list in priority order. From $2,500, re-run included. We never take payment to move a rank. We do help companies earn one.

Get an auditSee a sample report