Missing API/MCP support: image alt text, post tags, post deletion, and direct local-file upload

[b3cksy]

Hi there!,
Using the Postiz API/MCP tools (integrationSchedulePostTool, postSettingsTool, postsListTool, uploadFromUrlTool, uploadWidgetTool) to bulk-schedule a LinkedIn Page campaign, I ran into four gaps between what the Postiz UI/platforms support and what's exposed programmatically:

1. No way to upload a local file directly via the API/MCP tools

uploadFromUrlTool only accepts a publicly fetchable URL - it fails on anything requiring auth or blocked by robots.txt (e.g. a OneDrive/SharePoint "anyone with the link" share). The only other option, uploadWidgetTool, opens an interactive picker that a human has to complete by hand - there's no way for an agent/script to hand over local file bytes directly (e.g. a base64 payload or multipart upload) to get back a hosted media URL. In practice this means any automated workflow is blocked from attaching an image that lives only on the user's own machine/drive unless a person manually re-uploads it through the widget for every single post.

2. No way to update the publish date of an existing post

postSettingsTool explicitly only changes provider settings - "the content and the publish date stay exactly as they are." There is no equivalent tool to reschedule an existing draft/scheduled post to a new date. The only current workaround is deleting the post and recreating it from scratch (and deletion itself isn't possible via the API either - see #4) - meaning a simple "push my whole campaign back by a week" requires recreating every single post.

3. No alt text field for image attachments

integrationSchema for linkedin / linkedin-page returns no field for image alt text in its settings schema, and postsAndComments[].attachments only accepts an array of URLs with no accompanying metadata. LinkedIn's own API supports alt text on media, and it matters for accessibility. Could attachments accept {url, altText} objects instead of (or in addition to) plain strings?

4. No way to set post tags/labels via the API

The Postiz calendar UI has a tagging/labeling feature for organizing posts, but neither integrationSchedulePostTool nor postSettingsTool exposes a tags field. Would be useful to set/update tags programmatically when bulk-scheduling a large campaign (50+ posts), to keep them organized by category without manually tagging each one afterward in the UI.

5. No way to delete a post via the API

Both postsListTool's description and documentation state explicitly that posts cannot be deleted through the API/MCP tools - only through the UI. When scripting a bulk draft/schedule workflow, having to manually delete mistakes (e.g., a wrong pilot post, duplicate, or test entry) one-by-one in the UI is the main friction point. A posts:delete equivalent exposed via the API/MCP tools (matching the CLI's postiz posts:delete , if that's already wired to a real endpoint) would close this gap.

Context: found while scheduling a 51-post LinkedIn Page drafting campaign via the postiz MCP server / CLI tools.

[arslan2012]

Two of the five exist in the public REST API already. The MCP tools just don't expose them, so you can call these directly with the same API key:

1. Delete: DELETE /public/v1/posts/{id} (documented at docs.postiz.com/public-api/posts/delete). Note that deleting a post deletes its whole group. There's also DELETE /public/v1/posts/group/{group}.
2. Reschedule or edit: there's no PATCH, but POST /public/v1/posts updates in place when you pass the existing post's id. A maintainer confirmed this in [Feature Request] Public API: Add PATCH /posts/{id} endpoint for updating/rescheduling queued posts #1218. So pushing the campaign back a week is a POST with the same id and a new date, not delete and recreate.
3. Local file upload: POST /public/v1/upload takes multipart/form-data with the file in a field named file. It's the same route the UI uses, so your script can send the bytes and use the returned path in the post, with no public URL needed. If the instance sets RESTRICT_UPLOAD_DOMAINS, media has to come through this route anyway.
4. Alt text and tags: I can't find these in the public post schema either. Those look like real gaps, so they're worth separate feature requests.

Disclosure: I'm the developer of qpost.dev and its MCP server, qpost-mcp, a publishing API for YouTube, TikTok and Instagram, so it doesn't help with your LinkedIn campaign. I'm not affiliated with Postiz. I ran into the same agent-versus-UI gaps when designing it.