Channel Post

1---
2name: channel-post
3description: Compose and post formatted content to a Telegram channel -- MarkdownV2 escaping, message splitting, media ordering
4argument-hint: "[content to post]"
5---
6 
7# Channel Post
8 
9Compose and post formatted content to a Telegram channel with correct formatting.
10 
11## Steps
12 
131. **Identify target channel**:
14   - `chats(action="list")` to find the channel
15   - Channel chat_id is a negative number (e.g., -1001234567890) or @username
16 
172. **Compose content** with the user:
18   - Draft the message text
19   - Apply MarkdownV2 formatting (see escaping rules below)
20   - Determine if media attachments are needed
21 
223. **Handle media attachments** (if any):
23   - Photo with caption: `media(action="send_photo", chat_id="...", file_path="...", caption="...")` -- caption goes WITH the photo, not as a separate message
24   - Document: `media(action="send_document", chat_id="...", file_path="...")`
25   - Multiple photos: send as media group, first photo carries the caption
26 
274. **Split long messages** if content exceeds 4096 characters:
28   - Split at paragraph boundaries (double newline) to preserve readability
29   - Each chunk must be independently valid MarkdownV2 (no unclosed formatting)
30   - Send chunks sequentially with the same parse_mode
31 
325. **Send and verify**:
33   - `messages(action="send", chat_id="<channel>", text="<content>", parse_mode="MarkdownV2")`
34   - Verify the message appears correctly in the channel
35   - If formatting breaks, check the escaping rules below
36 
37## MarkdownV2 Escaping Rules
38 
39All these characters MUST be escaped with `\` when used as literal text (outside formatting markup):
40 
41```
42_ * [ ] ( ) ~ ` > # + - = | { } . !
43```
44 
45### Common patterns
46 
47| Intent | Correct MarkdownV2 |
48|---|---|
49| Bold text | `*bold*` |
50| Italic text | `_italic_` |
51| Code inline | `` `code` `` |
52| Code block | ```` ```language\ncode\n``` ```` |
53| Link | `[text](https://url)` |
54| Literal dot in "v2.0" | `v2\.0` |
55| Literal dash in list | `\- item` |
56| Price "$9.99" | `\$9\.99` |
57| Exclamation "Done!" | `Done\!` |
58| Parenthetical "(note)" | `\(note\)` |
59| Hashtag "#topic" | `\#topic` |
60 
61### Formatting inside formatting
62 
63When nesting, the inner delimiter must also be escaped:
64- Bold italic: `*_bold italic_*` -- the `_` inside `*...*` does NOT need escaping
65- But literal `_` inside bold: `*score\_value*` -- MUST escape
66 
67### Frequent mistakes
68 
69- Forgetting to escape `.` in URLs used as plain text (not inside `[](...)`)
70- Forgetting to escape `!` at end of sentences
71- Forgetting to escape `-` in bulleted lists (use `\-` or switch to HTML `<li>`)
72- Unescaped `(` `)` in regular text (Telegram interprets them as link syntax)
73 
74## When to Use
75 
76- Publishing announcements, updates, or newsletters to a Telegram channel
77- Posting formatted content (code snippets, tables, lists) to channels
78- Sending content with images or documents to channels
79- Any message that needs careful MarkdownV2 formatting
80