| Bluesky | ||
|---|---|---|
| Characters | 300 | 2,000 |
| Media | optional | optional |
| Hashtags | 1-2 specific hashtags | 1-3 hashtags |
| Links in body | fine | fine |
| Needs platform approval | no | yes |
Bluesky caps at 300 characters, Facebook allows 2,000. Posting the short version verbatim wastes the room Facebook gives you to actually explain the thing.
Bluesky: 1-2 specific hashtags. Facebook: 1-3 hashtags. Carrying the tag block across is the single most obvious sign of an automated cross-post.
You can post to Bluesky today with a credential you generate yourself. Facebook gates posting behind a platform review — see our API approval notes for what that actually takes.
Bluesky is indie and anti-corporate — polished brand voice reads badly. Facebook is warm and community-toned; 40-80 characters peaks engagement. Those are different jobs, so the same words cannot do both well — and every algorithm here demotes text that obviously was not written for it. The fix is not to skip cross-posting; it is to send a native version to each network.
curl -X POST https://postwire.io/api/post \
-H "Authorization: Bearer $POSTWIRE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"platforms": ["bluesky", "facebook"],
"text": "Your post",
"per_platform": {
"bluesky": { "text": "The Bluesky version" },
"facebook": { "text": "The Facebook version" }
}
}'
PostWire's /api/generate writes those per-platform versions for you from a single prompt, respecting
every limit in the table above. From an AI agent it is one MCP tool call.
Other pairs: Facebook to Bluesky · all combinations · which APIs need approval