# Channel Compatibility This guide defines the normative capability matrix across nativeMsg-supported channel types, provides channel identifier reference strings, and specifies the rules for designing experiences that degrade gracefully across channels. ## Channel Identifier Strings The following strings are used in the action `channel` property and the condition `channelTypes` field. | Identifier | Channel Type | Description | | ---------- | --------------------------- | ------------------------------------------------------------ | | `rcs` | Rich Communication Services | RCS Business Messaging over the native Android messaging app | | `dsc` | DSC | Direct-to-consumer messaging channel with rich card support | | `dlc` | DLC | 10DLC SMS/MMS messaging (limited formatting) | {% hint style="info" %} Channel identifier strings are case-sensitive. `"RCS"` and `"rcs"` are not equivalent in condition or action channel fields. {% endhint %} ## Feature × Channel Capability Matrix The table below lists every schema feature and its support status per channel. Where a feature is supported, the exact maximum or constraint is stated. Where a feature is unsupported, the degradation behavior is noted. | Feature | RCS | DSC | DLC | | ---------------------------------------- | ------------------------------- | --------------------- | ----------------------------------------------------------------------------- | | **Text message** | ✓ Max 3072 chars | ✓ Max 3072 chars | ✓ Max 160 chars per SMS segment; longer messages split into multiple segments | | **Message title** | ✓ Max 200 chars | ✓ Max 200 chars | ✗ Ignored | | **Media — image** | ✓ JPEG, PNG, GIF, WebP | ✓ JPEG, PNG, GIF | ✓ MMS only; file size limits apply per carrier | | **Media — video** | ✓ MP4, WebM | ✓ MP4 | ✗ Not supported | | **Media — audio** | ✓ MP3, OGG, WAV | ✗ Not supported | ✗ Not supported | | **Media — file** | ✓ PDF and common document types | ✓ PDF | ✗ Not supported | | **Buttons — total per message** | Max 4 | Max 4 | ✗ Not supported | | **Button type: weburl** | ✓ | ✓ | ✗ | | **Button type: postback** | ✓ | ✓ | ✗ | | **Button type: call** | ✓ | ✓ | ✗ | | **Button type: text** | ✓ | ✓ | ✗ | | **Button type: location** | ✓ | ✗ | ✗ | | **Button type: viewLocation** | ✓ | ✗ | ✗ | | **Button type: calendar** | ✓ | ✗ | ✗ | | **Button type: datetime** | ✓ | ✗ | ✗ | | **Button title max** | 25 chars | 25 chars | N/A | | **Button payload max** | 1000 chars | 1000 chars | N/A | | **Quick replies** | ✓ Max 13 | ✓ Max 13 | ✗ Not supported | | **Quick reply title max** | 25 chars | 25 chars | N/A | | **Quick reply — image** | ✓ (`imageUrl`) | ✓ (`imageUrl`) | ✗ | | **Quick reply type: location** | ✓ | ✗ | ✗ | | **Quick reply type: datetime** | ✓ | ✗ | ✗ | | **Quick reply type: calendar** | ✓ | ✗ | ✗ | | **Carousel** | ✓ Min 2, Max 10 cards | ✓ Min 2, Max 10 cards | ✗ Not supported | | **List** | ✓ Min 2, Max 4 items | ✓ Min 2, Max 4 items | ✗ Not supported | | **Rich card (standalone)** | ✓ | ✓ | ✗ Not supported | | **Rich card — VERTICAL orientation** | ✓ | ✓ | ✗ | | **Rich card — HORIZONTAL orientation** | ✓ | ✓ | ✗ | | **Rich card title max** | 200 chars | 200 chars | N/A | | **Rich card description max** | 2000 chars | 2000 chars | N/A | | **Rich card buttons max** | 4 | 4 | N/A | | **mediaHeight: SHORT** | ✓ | ✓ | ✗ | | **mediaHeight: MEDIUM** | ✓ | ✓ | ✗ | | **mediaHeight: TALL** | ✓ | ✓ | ✗ | | **imageAlignment: LEFT / RIGHT** | ✓ (HORIZONTAL only) | ✓ (HORIZONTAL only) | ✗ | | **waitFor: text** | ✓ | ✓ | ✓ | | **waitFor: number** | ✓ | ✓ | ✓ | | **waitFor: datetime** | ✓ | ✓ | ✓ (typed by user) | | **waitFor: coordinates** | ✓ | ✓ | ✗ | | **waitFor: file** | ✓ | ✓ | ✗ | | **waitFor: quick reply** | ✓ | ✓ | ✗ | | **waitFor: multi select** | ✓ | ✓ | ✗ | | **send.email** | ✓ | ✓ | ✓ | | **send.request** | ✓ | ✓ | ✓ | | **send.note** | ✓ | ✓ | ✓ | | **send.rss** | ✓ | ✓ | ✗ | | **assignTags** | ✓ | ✓ | ✓ | | **assignAttributes** | ✓ | ✓ | ✓ | | **updateSettings.conversation.priority** | ✓ | ✓ | ✓ | | **updateSettings.rcsExperience.enabled** | ✓ | ✗ | ✗ | | **subscribe** | ✓ | ✓ | ✓ | | **Webview (webviewViewMode)** | ✓ full, half, tall | ✓ full, half, tall | ✗ | {% hint style="warning" %} Features listed as ✗ for a channel are silently ignored or cause a degraded experience — they do not produce a runtime error. Always test your experience on each target channel before deploying. {% endhint %} ## Designing for Cross-Channel Compatibility ### Normative Rules 1. **Channel-restrict rich actions.** Any action that uses a feature not supported on all target channels MUST include either a `channel` property (restricting execution to the capable channel) or a `conditions` array with a `channelTypes` filter. 2. **Always provide a text fallback.** For every rich-content action (`carousel`, `list`, `richCard`, `buttons`), a parallel action restricted to non-rich channels MUST be defined, sending equivalent information as plain text. 3. **Do not rely on button-triggered `execute` on DLC.** On DLC channels, buttons are not rendered and their `execute` callbacks never fire. All workflow branching on DLC MUST be driven by user-typed text or keyword matching. 4. **Quick replies MUST NOT be the only navigation mechanism.** Any workflow that relies on quick reply selection for progression MUST include a `waitFor` step accepting `"text"` in addition to `"quick reply"`, so text-only channel users can respond. 5. **Test DLC text length.** Messages intended for DLC MUST be designed to fit within 160 characters where possible, or explicitly planned for multi-segment delivery. Attribute placeholder substitution happens before length evaluation; account for the expanded text length. ### Channel-Restriction Pattern Use the `channel` property on actions to serve channel-appropriate content from a single workflow: ```json { "name": "Cross-Channel Announcement", "workflows": [ { "name": "send-announcement", "intents": ["announcement"], "actions": [ { "name": "rich-announcement-rcs", "channel": "rcs", "send": { "message": { "title": "New Feature: Live Order Tracking", "text": "Track your order in real time with our new interactive map.", "mediaType": "image", "media": "https://cdn.acme.com/features/live-tracking-preview.jpg", "richCard": { "cardOrientation": "VERTICAL", "mediaHeight": "MEDIUM" }, "buttons": [ { "type": "weburl", "title": "Try it now", "payload": "https://shop.acme.com/track" } ] } } }, { "name": "rich-announcement-dsc", "channel": "dsc", "send": { "message": { "title": "New Feature: Live Order Tracking", "text": "Track your order in real time with our new interactive map.", "buttons": [ { "type": "weburl", "title": "Try it now", "payload": "https://shop.acme.com/track" } ] } } }, { "name": "text-announcement-dlc", "channel": "dlc", "send": { "message": { "text": "New: Live order tracking is here! Visit acme.com/track to try it. Reply STOP to opt out." } } } ] } ] } ``` ### Condition-Based Channel Routing Use `conditions` with `channelTypes` when you need to branch execution logic (not just content) by channel: ```json { "name": "check-rcs-capable", "conditions": [ { "channelTypes": ["rcs", "dsc"] } ], "send": { "message": { "text": "Choose an option below:", "quickReplies": [ { "type": "text", "title": "Option A", "payload": "opt_a" }, { "type": "text", "title": "Option B", "payload": "opt_b" } ] } } } ``` ```json { "name": "dlc-text-prompt", "conditions": [ { "channelTypes": "dlc" } ], "send": { "message": { "text": "Reply A for Option A or B for Option B." } } } ``` ### RSS Feed Channel Restriction RSS feed rendering (`send.rss`) is only supported on RCS and DSC. Always restrict this action and provide a fallback: ```json { "name": "send-news-rcs", "channel": "rcs", "send": { "rss": { "url": "https://blog.acme.com/feed.xml", "preferedLayout": "carousel" } } } ``` ```json { "name": "send-news-dlc", "channel": "dlc", "send": { "message": { "text": "Read our latest articles at blog.acme.com" } } } ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://playbook.nativemsg.com/rcs-experience-schema/guides/channel-compatibility.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. 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