Supported Platforms

VoxBurst supports publishing to multiple social media platforms. Some are live and available today. Others are integrated and in the pipeline — their developer API applications are pending review and approval from each platform. Check the status column below before building against a specific platform.

Platforms overview

Platform Capabilities

Content Types by Platform

Use contentType on post creation to signal the format of your content. Platforms that do not support a content type will reject the post at validation time.

Content Limits

Cross-Platform Quick Comparison

* Mastodon character limit varies by instance. Default is 500.

Twitter / X

• Constant: TWITTER
• Character limit: 280 (links count as 23 characters regardless of length)
• Media: Up to 4 images, or 1 video (max 2:20), or 1 GIF
• Scheduling: ✅ Supported
• First comment: ✅ Supported
• Auth: OAuth 2.0 with PKCE — TWITTER_CLIENT_ID, TWITTER_CLIENT_SECRET

Supported content types

Validation rules

• 280 characters per tweet; links always count as 23 characters regardless of actual length
• Images: max 5 MB JPG/PNG, max 15 MB GIF, max 4 images per tweet
• Video: max 512 MB, max 2:20 duration, H.264, AAC audio
• Cannot mix images and video in a single tweet

Common failures

MCP example

create_post(
  content: "Just launched our new feature! 🚀 Check it out at the link below.",
  accountIds: ["acc_twitter_abc123"],
  contentType: "IMAGE",
  mediaUrls: ["https://cdn.example.com/feature-screenshot.jpg"]
)

LinkedIn

• Constant: LINKEDIN
• Character limit: 3,000 for posts
• Media: Up to 20 images, or 1 video (10 min max), or 1 PDF document
• Scheduling: ✅ Supported
• First comment: ✅ Supported
• Account types: Personal profiles and company pages (organization URN selection required for company pages)
• Auth: OAuth 2.0 — LINKEDIN_CLIENT_ID, LINKEDIN_CLIENT_SECRET

Supported content types

Validation rules

• 3,000 character limit for post text
• Company page posts require the connected account to have Admin or Content Admin role
• PDF documents max 100 MB; 300 page limit
• Video: max 5 GB, max 10 min; H.264 recommended

Common failures

MCP example

create_post(
  content: "Excited to share our latest case study. Here is what we learned about scaling content operations across 12 platforms.",
  accountIds: ["acc_linkedin_abc123"],
  contentType: "DOCUMENT",
  mediaIds: ["media_casestudy_pdf_abc123"]
)

Bluesky

• Constant: BLUESKY
• Character limit: 300 graphemes
• Media: Up to 4 images, or 1 video (3 min max)
• Scheduling: ✅ Supported
• First comment: ✗ Not supported
• Protocol: AT Protocol (atproto)
• Auth: App passwords — no OAuth app credentials required; users authenticate with their bsky.app app password

Supported content types

Validation rules

• 300 graphemes, not 300 characters — emoji count as 1 grapheme each
• Links are embedded as card previews; they count toward the 300 grapheme limit
• 4 images maximum; max 1 MB per image
• Video support added September 2024; max 3 min

Common failures

MCP example

create_post(
  content: "New blog post: How we built our content calendar from scratch. Link in thread.",
  accountIds: ["acc_bluesky_abc123"],
  contentType: "TEXT"
)

Instagram

• Constant: INSTAGRAM
• Character limit: 2,200 for captions
• Media: Required — at least 1 image or video (up to 10 per carousel); Reels supported
• Scheduling: ✅ Supported
• First comment: ✅ Supported
• Account types: Instagram Business or Creator accounts only
• Auth: OAuth 2.0 via Facebook Graph API — META_APP_ID, META_APP_SECRET
• Supported content types: IMAGE (single feed photo), VIDEO (feed video), CAROUSEL (2–10 images/videos), REEL (short-form video). Always set contentType when posting to Instagram.
• Stories: STORY is not supported — the Instagram Graph API does not allow third-party apps to publish Stories. Posts with contentType: STORY targeting Instagram will be rejected.

Supported content types

Validation rules

• Media is required on every post — no text-only posts
• contentType is required — omitting it causes rejection
• Aspect ratio: 4:5 to 1.91:1 (portrait to landscape); Reels should be 9:16
• Images must be JPEG, PNG (auto-converted to JPEG), or WebP (auto-converted)
• Video: max 90 seconds for feed; max 4K resolution; H.264 codec recommended
• Caption max 2,200 characters

Common failures

MCP example

See the full Post to Instagram via MCP guide for complete examples.

create_post(
  content: "Launch day. Shipping now. 🚀",
  accountIds: ["acc_instagram_abc123"],
  contentType: "CAROUSEL",
  mediaUrls: ["https://cdn.example.com/a.jpg", "https://cdn.example.com/b.jpg"],
  scheduledFor: "2026-06-01T15:00:00Z",
  firstComment: "Link in bio for details."
)

Facebook

• Constant: FACEBOOK
• Character limit: 63,206 characters
• Media: Up to 10 images or 1 video (4 hours max)
• Scheduling: ✅ Supported
• First comment: ✅ Supported
• Account types: Pages (personal profiles have limited API access); page ID selection required via POST /v1/accounts/:id/select-page
• Auth: OAuth 2.0 via Facebook Graph API — META_APP_ID, META_APP_SECRET

Supported content types

Validation rules

• Must be posting to a Facebook Page — personal profiles have limited API access
• 63,206 character limit (effectively unlimited for normal use)
• Video: max 10 GB, max 4 hours; H.264 recommended

Common failures

MCP example

create_post(
  content: "We are hiring! Three open roles on our engineering team. Apply at the link below.",
  accountIds: ["acc_facebook_abc123"],
  contentType: "IMAGE",
  mediaUrls: ["https://cdn.example.com/hiring-banner.jpg"]
)

Threads

• Constant: THREADS
• Character limit: 500 characters
• Media: Up to 10 images or 1 video (5 min max)
• Scheduling: ✅ Supported
• First comment: ✗ Not supported
• Note: Threads is a Meta platform; requires an Instagram Business or Creator account
• Auth: OAuth 2.0 — THREADS_APP_ID, THREADS_APP_SECRET (falls back to Meta credentials)

Supported content types

Validation rules

• Requires an Instagram Business or Creator account to be connected
• 500 character limit
• Video: max 5 minutes

Common failures

MCP example

create_post(
  content: "Big news coming tomorrow. Stay tuned. 🔔",
  accountIds: ["acc_threads_abc123"],
  contentType: "TEXT"
)

TikTok

• Constant: TIKTOK
• Character limit: 2,200 characters
• Media: Up to 35 images (photo mode carousel), or 1 video (3 sec–10 min, up to 4 GB)
• Scheduling: ✅ Supported
• First comment: ✅ Supported (requires comment.list.manage scope approval from TikTok)
• Video specs: H.264 or HEVC; up to 3840×2160; aspect ratios 9:16, 1:1, 4:5
• Auth: OAuth 2.0 — TIKTOK_CLIENT_KEY, TIKTOK_CLIENT_SECRET

YouTube

• Constant: YOUTUBE
• Character limit: 5,000 for video descriptions
• Media: Video required (up to 12 hours / 256 GB); thumbnail image optional
• Scheduling: ✅ Supported (native YouTube scheduling)
• First comment: ✅ Supported
• Shorts: Videos ≤60 seconds in 9:16 format are automatically published as YouTube Shorts
• Rate limit: 6 uploads per day, 3 per hour
• Auth: OAuth 2.0 via Google — GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET

Supported content types

Validation rules

• Video is required; no other media types accepted as standalone posts
• Thumbnails may be uploaded as companion media but are not published independently
• Videos ≤60 seconds in 9:16 aspect ratio automatically become YouTube Shorts
• Max 6 uploads per day, 3 per hour (YouTube Data API quota)
• Video description max 5,000 characters

Common failures

MCP example

create_post(
  content: "How we built our content calendar from scratch — full walkthrough",
  accountIds: ["acc_youtube_abc123"],
  contentType: "VIDEO",
  mediaIds: ["media_video_abc123"],
  scheduledFor: "2026-06-02T16:00:00Z",
  firstComment: "Full article in the description. Subscribe for more."
)

Pinterest

• Constant: PINTEREST
• Character limit: 500 for pin descriptions
• Media: Up to 5 images (carousel pin), or 1 video (max 1 min)
• Scheduling: ✅ Supported
• First comment: ✗ Not supported
• Note: Pins require a destination link URL. Carousel (multi-image) pins are supported.
• Auth: OAuth 2.0 — PINTEREST_CLIENT_ID, PINTEREST_CLIENT_SECRET

Reddit

• Constant: REDDIT
• Character limit: 40,000 for self (text) posts
• Media: 1 image only — JPEG, PNG, or GIF (gallery/multi-image and video upload not yet implemented)
• Scheduling: ✅ Supported
• First comment: ✗ Not supported
• Note: Posts require a target subreddit. Link posts and text posts are also supported.
• Auth: OAuth 2.0 — REDDIT_CLIENT_ID, REDDIT_CLIENT_SECRET, REDDIT_USER_AGENT

Snapchat

• Constant: SNAPCHAT
• Character limit: 80 characters
• Media: 1 image or 1 video (max 1 min) — published to Spotlight or Story via the Snapchat Marketing API
• Scheduling: ✅ Supported
• First comment: ✗ Not supported
• Note: Requires a Snapchat Business/Ads account. Limited to the marketing API — direct personal account posting is not supported.
• Auth: OAuth 2.0 — SNAPCHAT_CLIENT_ID, SNAPCHAT_CLIENT_SECRET

Telegram

• Constant: TELEGRAM
• Character limit: 4,096 characters (caption limit: 1,024 chars when media is attached)
• Media: Up to 10 images (media group), or 1 video (max 1 hour), or documents
• Scheduling: ✅ Supported (native Telegram scheduled messages)
• First comment: ✗ Not supported
• Note: Posts to a Telegram channel or group that the bot administers. Each connected account uses its own bot token — no shared app credentials required.
• Auth: Bot tokens from @BotFather  — stored per-account in Secrets Manager; no TELEGRAM_* app env vars needed

Google Business Profile

• Constant: GOOGLE_BUSINESS
• Character limit: 1,500 characters for post summaries
• Media: Up to 10 images or 1 video (max 30 sec)
• Scheduling: ✅ Supported
• First comment: ✗ Not supported
• Post types: Updates, Offers, and Events — post type is selectable when creating the post
• Auth: OAuth 2.0 via Google (Business API scope) — GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET

Mastodon

• Constant: MASTODON
• Character limit: 500 characters (default; varies by instance — some instances allow up to 5,000)
• Media: Up to 4 images or 1 video (max 5 min)
• Scheduling: ✅ Supported (native Mastodon scheduled posts)
• First comment: ✗ Not supported
• Note: Mastodon is decentralized; each account specifies its instance URL (e.g., mastodon.social). OAuth credentials are registered per-instance.
• Auth: OAuth 2.0 — per-instance credentials; instanceUrl required at account connection time

Supported content types

Validation rules

• Character limit depends on the instance — default is 500, but some allow 5,000+
• instanceUrl required at account connection time (e.g. mastodon.social, fosstodon.org)
• Images: max 8 MB; videos: max 40 MB (default Mastodon limits)

Common failures

MCP example

create_post(
  content: "Just published a new article on decentralized social media. Thoughts? #Mastodon #Fediverse",
  accountIds: ["acc_mastodon_abc123"],
  contentType: "TEXT"
)

WhatsApp Business

• Constant: WHATSAPP
• Character limit: 4,096 characters
• Media: Up to 30 images or 1 video (max 3 min); documents also supported
• Scheduling: ✅ Supported
• First comment: ✗ Not supported
• Note: Requires a WhatsApp Business API account with Meta Business verification. Messages are sent to opted-in contacts or published to WhatsApp Status (Stories).
• Auth: OAuth 2.0 via Meta Business API — WHATSAPP_APP_ID, WHATSAPP_APP_SECRET

Platform Capabilities API

Get capability information for a specific platform:

curl https://api.voxburst.io/v1/platforms/twitter \
  -H "Authorization: Bearer vb_live_xxxxxxxxxxxxx"

Response

{
  "platform": "TWITTER",
  "name": "Twitter / X",
  "maxTextLength": 280,
  "maxImages": 4,
  "maxVideoLength": 140,
  "supportsThreads": true,
  "supportsCarousels": false,
  "supportsStories": false,
  "supportsReels": false,
  "supportsScheduling": false,
  "supportsFirstComment": true,
  "supportsComments": true,
  "supportsAnalytics": true,
  "supportsOptimalTimes": true,
  "mediaTypes": ["image/jpeg", "image/png", "image/gif", "video/mp4"],
  "rateLimit": { "postsPerDay": 2400, "postsPerHour": 100 }
}

List all platforms at once:

curl https://api.voxburst.io/v1/platforms \
  -H "Authorization: Bearer vb_live_xxxxxxxxxxxxx"