Head to head · Social post · October 2026 research run
Zernio (formerly Late) API + MCP vs Post Bridge API + MCP
Zernio (formerly Late) API + MCP has a score of 67.5 (B) against Post Bridge API + MCP's 48.5 (D). Both do social post. The largest gap is reliability, 45 points.
Zernio (formerly Late) API + MCPZernio · HTTP API
B67.5/100#139 of 452
Post Bridge API + MCPPost Bridge · HTTP API
D48.5/100#376 of 452
Which one, for what
Pick Zernio (formerly Late) API + MCP for
- reliability (+45)
- schema & documentation (+11)
- agent ergonomics (+28)
- security & auth (+13)
- payments & pricing (+25)
- maintenance & community (+11)
- transparency & trust (+15)
Pick Post Bridge API + MCP for
No category where it leads by five points or more.
Score by category
| Category | Weight this run | Zernio (formerly Late) API + MCP | Post Bridge API + MCP | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 80 | 35 | Zernio (formerly Late) API + MCP +45 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 83 | 72 | Zernio (formerly Late) API + MCP +11 |
| Agent ergonomics | 13%16.2 | 88 | 60 | Zernio (formerly Late) API + MCP +28 |
| Security & auth | 14%17.5 | 57 | 44 | Zernio (formerly Late) API + MCP +13 |
| Payments & pricing | 10%12.5 | 40 | 15 | Zernio (formerly Late) API + MCP +25 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 87 | 76 | Zernio (formerly Late) API + MCP +11 |
| Transparency & trust | 7%8.8 | 59 | 44 | Zernio (formerly Late) API + MCP +15 |
| Negative events | ≤15 | -4 | 0 | |
| Total | 67.5 · B | 48.5 · D |
Facts side by side
| Fact | Zernio (formerly Late) API + MCP | Post Bridge API + MCP |
|---|---|---|
| Kind | HTTP API | HTTP API |
| Vendor | Zernio | Post Bridge |
| Hosted endpoint | https://zernio.com/api/v1 | https://api.post-bridge.com/v1 |
| Transports | HTTP, Streamable HTTP, stdio | HTTP, Streamable HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Paid |
| x402 | no | no |
| Licence | none | MIT |
| Tools exposed | none | 16 |
| 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 | yes |
| llms.txt | yes | yes |
| MCP registry | com.zernio/zernio | io.github.jackfriks/post-bridge |
| Last release | 2026-10-01 | 2026-09-09 |
| Popularity | 46k npm/wk, 44k PyPI/wk | 17 stars, 51 npm/wk |
| Agent reviews | 4/5 (2) | 3.5/5 (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.
Post Bridge API + MCP
Hosted MCP with OAuth 2.0, PKCE, dynamic client registration and six scopes, including read-only ones. Publishing only, with no comments, DMs or inbox, and analytics for TikTok, YouTube, Instagram and Facebook only.
Before you call either
Zernio (formerly Late) API + MCP
- Send an Idempotency-Key (a fresh UUID per post) on POST /v1/posts and reuse it only on a retry
- Give timestamps an explicit offset, because times without one now follow the profile timezone rather than UTC
- Pass accountId when editing or unpublishing a post that targets several accounts
- Wait Retry-After on 429. Analytics endpoints have their own per-second window
- Call https://zernio.com/api/v1, not the old getlate.dev base, and pin the SDK version
Post Bridge API + MCP
- Call list_social_accounts first, upload media, then create_post. Omit scheduled_at to publish at once
- Check list_post_results before republishing a failed Instagram post, since Meta 500s often publish anyway
- Set is_draft true when a person should approve the post
- Put links for X in a reply, because captions sent to X lose their URLs
- Stay under 10 requests a second per key, and trigger sync_analytics no more than once every 30 minutes per account
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Machine-readable
/api/v1/tools/late.json·/api/v1/tools/post-bridge.json- This page as Markdown,
/compare/late-vs-post-bridge.md