Custom replies include the familiar first comment and additional follow-up comments or replies. In the editor, expand Custom replies (first comment) in Preview, beneath timing guidance. Add a shared text-and-link sequence, then choose Use shared replies, Custom, or Off per supported selected platform. Edit custom sequences in the existing platform settings.
Shared replies in CSV and Google Sheets
The shared columns appear immediately after post_content: custom_replies_1, custom_replies_delay_minutes_1, then matching pairs for replies 2 and 3. Add numbered pairs up to 50 when needed. For example, put Read more: https://example.com/page in custom_replies_1 and 15 in its delay column. Shared replies support text and ordinary links; use platform overrides for attachments.
A platform-specific sequence replaces the entire shared sequence for that platform; sequences never append automatically. An optional x_custom_replies_mode (replace x with a supported platform) accepts shared, custom, or off. Off suppresses replies, including presets. Blank mode uses a supplied platform sequence, otherwise shared replies. Leave unused reply cells blank. Header notes and the add-on instructions explain these fields; instructional text is never an import row.
Platform overrides
Author CSV and Google Sheets replies in the file or sheet cells. CSV preview does not edit replies.
Use facebook_custom_replies_1 and facebook_custom_replies_delay_minutes_1. Add pairs numbered 2, 3 and onward up to 50. Supported prefixes are facebook, instagram, linkedin, youtube, x, threads, and bluesky. Replies are scoped to that platform's selected channels. Unselected platforms do not receive replies.
Delay is whole minutes after the parent publishes, from 0 to 525600. Zero or an omitted delay means immediately; 15 means fifteen minutes; 1440 means a day. Delays are not cumulative. Leave both cells blank for unused slots. The parent uses the workspace timezone; save Asia/Tokyo in workspace settings when scheduling Japan local times.
URLs and attachments
Facebook, Instagram, LinkedIn and YouTube columns show only this text-and-link example:
Read more: https://example.com/page
X, Threads and Bluesky columns show these supported syntax alternatives:
Read more: https://example.com/page
[image](https://example.com/photo.jpg)
[video](https://example.com/video.mp4)
These examples show alternatives. Remove unused sample content before submitting. Plain URLs stay in the reply. Explicit image/video markers become attachments and are removed from the text. Use public HTTP(S) media URLs; encode parentheses in URLs as %28 and %29. Media is checked before admission.
| Platforms | Custom reply content |
|---|---|
| Facebook, Instagram, LinkedIn, YouTube | Text and ordinary links |
| X, Bluesky | Text, up to four images or one video |
| Threads | Text, up to twenty images or one video |
Do not mix images and video in one reply. Provider limits and account permissions still apply. A successful parent does not guarantee every reply succeeds; inspect publishing results before retrying.
API and MCP
Supply a top-level custom_replies array for shared replies, and optional custom_reply_modes mapping supported platform identifiers to shared, custom, or off. Omitted shared replies and modes are preserved on update; custom_replies: [] clears the shared sequence. Explicit platform replies replace the shared sequence, and an explicit empty platform array opts out. Existing platform replies remain custom unless switched to shared. Shared replies take precedence over saved presets on new requests; selected platforms that do not support replies receive none. Each receiving destination is validated before scheduling: overlong text or unsupported media is rejected, never truncated or silently removed.
{
"workspace": "YOUR_WORKSPACE_ID",
"target_platforms": "facebook,instagram",
"text": "Our latest update",
"custom_replies": [{"text": "Read more: https://example.com/page", "delay_minutes": 15}],
"custom_reply_modes": {"facebook": "shared", "instagram": "off"}
}
This is a create-post request body; authenticate using your API key. MCP uses the same fields and API implementation. Read-back responses retain shared replies and modes, while platform settings retain their compatibility fields. To customize one platform, supply custom_replies inside each platform_posts entry's settings. MCP create/validate tools use the same settings; request postly.get_channel_schema for destination guidance.
{
"identifier": "x",
"settings": {
"identifier": "x",
"publishing_mode": "classic",
"custom_replies": [
{"text": "Read more: https://example.com/page", "delay_minutes": 0},
{"text": "Photo [image](https://example.com/photo.jpg)", "delay_minutes": 15}
]
}
}
This is a platform settings fragment, not a complete create-post request. Supply the parent text/media, workspace, targets and parent schedule in the normal request. Explicit media objects { "type": "image", "url": "https://example.com/photo.jpg" } can also be supplied in a reply's media array.
Bulk API /bulk-posts accepts the same numbered platform columns as CSV/Sheets. Existing first-comment columns and API fields remain supported. Do not combine numbered replies with a legacy first-comment column for the same platform, or custom_replies with that platform's legacy reply list. Explicit replies override saved reply presets.
X modes and sensitive content
Choose one: classic, long_form, thread. numbered_thread remains supported. For a parent video plus a separately written follow-up, use classic plus custom replies; automatic thread splitting is not required. Long-form availability depends on the connected X account/API access.
Postly permits sensitive X content subject to applicable law and X rules. Use X's required media labeling and retain rights and consent for the content. This does not imply eligibility for paid X advertising or bypass third-party restrictions.
Compatibility and editing
Use custom_replies for new API and MCP integrations. Each entry has its own delay_minutes, measured from parent publication. Existing first_comment and platform reply fields remain accepted for compatibility. Responses retain legacy fields and expose custom_replies for supported platform settings. Send the canonical field when editing replies; conflicting canonical and legacy values are rejected instead of publishing duplicates.