trypostit · paulocastellano · Sep 13, 2026 · Sep 12, 2026 · Sep 12, 2026 · Sep 12, 2026
diff --git a/ai/tools-reference.mdx b/ai/tools-reference.mdx
@@ -102,7 +102,7 @@ Attach a library file to a post. Does **not** upload a new file. REST: [`POST /p
 
 | Tool | Description |
 |------|-------------|
-| **list-content-types-tool** | Returns `{ platforms: [...] }` — same catalog as [`GET /content-types`](/api-reference/endpoint/list-content-types). Each platform has `max_content_length`, `recommended_content_length`, `allowed_media_types`, `default_content_type`, and `content_types[]` rows with `max_media_count`, `min_media_count`, `requires_media`, `accept_images` / `accept_videos` / `accept_documents` / `accepts_gif`, `forbids_mixed_media`, and per-type byte caps. **20** content types total — there is no `linkedin_carousel` / `instagram_carousel`. Use before `create-post-tool` / `update-post-tool`. |
+| **list-content-types-tool** | Returns `{ platforms: [...] }` — same catalog as [`GET /content-types`](/api-reference/endpoint/list-content-types). Each platform has `max_content_length`, `recommended_content_length`, `allowed_media_types`, `default_content_type`, and `content_types[]` rows with `max_media_count`, `min_media_count`, `requires_media`, `accept_images` / `accept_videos` / `accept_documents` / `accepts_gif` / `accepts_mov`, `forbids_mixed_media`, and per-type byte caps. **20** content types total — there is no `linkedin_carousel` / `instagram_carousel`. Use before `create-post-tool` / `update-post-tool`. |
 
 ## Signatures
 

diff --git a/api-reference/endpoint/attach-media-from-url.mdx b/api-reference/endpoint/attach-media-from-url.mdx
@@ -41,7 +41,7 @@ For uploading a file directly from your machine instead of fetching a URL, use [
 
 - The post must belong to the caller's current workspace; otherwise the response is `404`.
 - Allowed media types are **intersected with the platforms enabled on the post**. If an enabled platform doesn't support the file type (e.g. video on a platform that's image-only), that file is rejected and listed in `failed_urls`.
-- Successful attachments are appended to the post's `media[]` array (image `alt` becomes `media[].meta.alt_text`).
+- Successful attachments are appended to the post's `media[]` array with `size` and `meta` (image `alt` becomes `media[].meta.alt_text`; videos carry `meta.duration` read from the file). Per-network size, duration, GIF and MOV caps are enforced when the post is scheduled or published — see [Media → Enforced on the server](/knowledge-base/media#enforced-on-the-server-not-just-in-the-editor).
 
 ## Response
 

diff --git a/api-reference/endpoint/list-content-types.mdx b/api-reference/endpoint/list-content-types.mdx
@@ -40,12 +40,15 @@ Returns `{ "platforms": [ ... ] }` — one object per social platform.
 | `accept_videos` | Whether videos are allowed. |
 | `accept_documents` | Whether PDFs are allowed (e.g. LinkedIn document posts). |
 | `accepts_gif` | Whether GIF is accepted as an image. |
+| `accepts_mov` | Whether QuickTime/MOV is accepted. `false` on Bluesky (MP4 only). |
 | `forbids_mixed_media` | When `true`, do not mix images and videos in one post. |
-| `max_video_duration_sec` | Max video length in seconds, or `null`. |
-| `max_image_bytes` | Max image size in bytes, or `null`. |
-| `max_video_bytes` | Max video size in bytes, or `null`. |
+| `max_video_duration_sec` | Max video length in seconds, or `null`. TikTok reports the 10-minute API ceiling; `creator_info` may lower it per account. |
+| `max_image_bytes` | Max image size in bytes, or `null`. Already clamped to the instance upload cap. |
+| `max_video_bytes` | Max video size in bytes, or `null`. Already clamped to the instance upload cap (Cloud: 1 GB, so X's 8 GB reads as 1 GB here). |
 | `max_document_bytes` | Max PDF size in bytes, or `null`. |
 
+Byte and duration caps are enforced server-side on publish/schedule as well as in the editor — see [Media → Enforced on the server](/knowledge-base/media#enforced-on-the-server-not-just-in-the-editor).
+
 ### Current `content_type` values (20)
 
 | Platform | Values |
@@ -91,6 +94,7 @@ Returns `{ "platforms": [ ... ] }` — one object per social platform.
           "accept_videos": true,
           "accept_documents": true,
           "accepts_gif": false,
+          "accepts_mov": true,
           "forbids_mixed_media": true,
           "max_video_duration_sec": 600,
           "max_image_bytes": 5242880,

diff --git a/api-reference/endpoint/request-media-upload.mdx b/api-reference/endpoint/request-media-upload.mdx
@@ -49,7 +49,7 @@ Send as `multipart/form-data` with a single `media` field.
 
   The FormRequest upper bound is the video ceiling; the per-type cap is enforced after MIME detection. MIME is detected from the file's magic bytes (not the extension or `Content-Type` header).
 
-  `request-media-upload-tool` also returns these limits as `max_bytes` (video ceiling) and `max_bytes_by_type`.
+  `request-media-upload-tool` also returns these limits as `max_bytes` (video ceiling) and `max_bytes_by_type`. These are the workspace-wide ceilings; each network's own size, duration, GIF and MOV caps (`list-content-types-tool`) are enforced when the post is scheduled or published. A video's `duration` is read from the file on the server and stored in `meta`.
 </ParamField>
 
 ## Authentication

diff --git a/api-reference/endpoint/update-post.mdx b/api-reference/endpoint/update-post.mdx
@@ -67,6 +67,7 @@ description: "Update a post's content, schedule, enabled platforms, or labels
 - On update, `meta` is **merged** into the platform's existing object. Send a key as `null` to remove it (e.g. `"title": null`).
 - Required-to-publish keys are enforced on this request when `status` is `scheduled` or `publishing` **and** you include a `platforms[]` array in the body (each submitted row is checked). Drafts are not checked. A missing key returns `422` on `platforms.{i}.meta.{field}` (e.g. `platforms.0.meta.channel_id`).
 - If you publish with only `{ "status": "publishing" }` (no `platforms[]`), this endpoint does **not** re-validate stored meta — ensure `board_id` / `privacy_level` / `channel_id` were saved earlier. The MCP `publish-post-tool` always validates stored meta before publishing.
+- **Media compatibility is always re-checked** on `scheduled` / `publishing`, with or without `platforms[]`: every enabled platform's effective `content_type` is validated against the post's effective media (media kind, GIF/MOV acceptance, byte cap via `size`, and video duration read from the file on upload). A failure is `422` on `platforms.{i}.content_type`, e.g. `Video exceeds the 300 MB limit for this post type (yours is 900.0 MB).` — see [Media → Enforced on the server](/knowledge-base/media#enforced-on-the-server-not-just-in-the-editor).
 - Enum-like fields are **JSON strings** — send the exact literal (e.g. `"privacy_level": "PUBLIC_TO_EVERYONE"`), not an integer or a different casing.
 - Platforms with **no** `meta` keys: X, YouTube, Threads, Bluesky, Mastodon, Telegram.
 

diff --git a/api-reference/endpoint/upload-media.mdx b/api-reference/endpoint/upload-media.mdx
@@ -30,7 +30,7 @@ Send as `multipart/form-data` with a single `media` field.
 - The file's MIME type is **intersected with the platforms enabled on the post**. For example, uploading an image to a TikTok-only post returns `422` unless the post targets `tiktok_photo`. Uploading a PDF only succeeds on platforms that accept documents (e.g. LinkedIn `linkedin_post`).
 - Per-type size caps are enforced after MIME detection. The FormRequest uses the video ceiling as an overall bound; per-type limits still apply.
 - PNG and WebP still images are normalized to **JPEG (q100)** at storage time for universal platform compatibility. GIF is preserved (animation kept for X / Bluesky / Mastodon / Telegram / Discord). MP4, MOV, and PDF are stored as-is.
-- The new media is stored under `medias/{uuid}.{ext}` on the configured filesystem disk (`local`, `s3`, or `r2`) and appended to the post's `media[]` array.
+- The new media is stored under `medias/{uuid}.{ext}` on the configured filesystem disk (`local`, `s3`, or `r2`) and appended to the post's `media[]` array with its `size` and `meta` (image `width`/`height`, video `duration` in seconds read from the file). Per-network size, duration, GIF and MOV caps are enforced when the post is scheduled or published — see [Media → Enforced on the server](/knowledge-base/media#enforced-on-the-server-not-just-in-the-editor).
 
 ## Response