feat(schema): add 3gp, mpeg and m4v to video containers (#8107)

.changeset/video-containers-3gp-mpeg-m4v.md

@@ -0,0 +1,5 @@
+---
+"adcontextprotocol": minor
+---
+
+Add `3gp`, `mpeg`, and `m4v` to the `containers` enum of the video asset requirements (`core/requirements/video-asset-requirements.json`), so a seller that accepts those files can declare them. Three additive enum values: no existing value changes, and clients already tolerate unknown enum values. Proposed for 3.3 by consent (adcp#8107).

docs/reference/3-3-beta.mdx

@@ -198,7 +198,7 @@ Four proposed records document surfaces merged for beta.0 and await working-grou
 | Creative and brand | [#5375](https://github.com/adcontextprotocol/adcp/issues/5375) | `build_creative` refinement scope | — | Compliance carries forward across refinement (#7937) |
 | Creative and brand | [#4282](https://github.com/adcontextprotocol/adcp/issues/4282) | Provenance on listed and delivered creative variants | — | Creative-level `provenance` on `list_creatives` (#8063) |
 | Creative and brand | [#8048](https://github.com/adcontextprotocol/adcp/issues/8048) | Brand-wide `prohibited_terms` in brand.json | — | `prohibited_terms` on the brand.json brand definition (#8056) |
-| Creative and brand | [#8107](https://github.com/adcontextprotocol/adcp/issues/8107) | `3gp`, `mpeg`, and `m4v` video containers | — | — |
+| Creative and brand | [#8107](https://github.com/adcontextprotocol/adcp/issues/8107) | `3gp`, `mpeg`, and `m4v` video containers | — | `3gp`, `mpeg`, and `m4v` added to the video `containers` enum (proposed by consent, objections by 2026-11-06) |
 | Creative and brand | [#8092](https://github.com/adcontextprotocol/adcp/issues/8092) | Creator and show cards on collections | — | Collection cards, follower counts, response collections, and `list_collections` (#8094, #8098, #8141, #8279) |
 | Creative and brand | [#6348](https://github.com/adcontextprotocol/adcp/issues/6348) | Anchored creative feedback and per-party review records | — | — |
 | Signals, audiences, catalogs | [#8023](https://github.com/adcontextprotocol/adcp/issues/8023) | Audience overlap read | [#8031](https://github.com/adcontextprotocol/adcp/pull/8031) (draft) | Audience size ranges (#8024) |

static/schemas/source/core/requirements/video-asset-requirements.json

@@ -44,9 +44,9 @@
       "type": "array",
       "items": {
         "type": "string",
-        "enum": ["mp4", "webm", "mov", "avi", "mkv"]
+        "enum": ["mp4", "webm", "mov", "avi", "mkv", "3gp", "mpeg", "m4v"]
       },
-      "description": "Accepted video container formats"
+      "description": "Accepted video container formats. The `3gp`, `mpeg`, and `m4v` values were added in AdCP 3.3. `mpeg` is an MPEG-1 or MPEG-2 program stream (`video/mpeg`), not an MPEG transport stream."
     },
     "codecs": {
       "type": "array",

tests/x-added-in-3-3-sweep.test.cjs

@@ -182,6 +182,7 @@ test('added enum values are noted in the enum description', () => {
   const video = load('formats/canonical/video_hosted.json').properties;
   assert.match(video.video_codecs.description, /`mpeg2`, `avc_intra`, and `xavc`.*3\.3/);
   assert.match(video.containers.description, /`mxf`.*3\.3/);
+  assert.match(load('core/requirements/video-asset-requirements.json').properties.containers.description, /`3gp`, `mpeg`, and `m4v`.*3\.3/);
 });
 
 test('surfaces shipped in 3.2 are not marked 3.3', () => {