Question 1

Which characters does Telegram MarkdownV2 require to be escaped?

Accepted Answer

Eighteen characters in normal text: _, *, [, ], (, ), ~, ` `, >, #, +, -, =, |, {, }, ., !. Inside ` and `` code blocks only ` and \ need escaping; inside the URL part of an inline link text only ) and \` need escaping. The list is published verbatim in the Bot API formatting documentation.

Question 2

Why does my Telegram bot post nothing — no error, no message?

Accepted Answer

Telegram is returning HTTP 400 ok: false with a precise description field, but your code is swallowing it. Three usual suspects: a try: ... except Exception block that catches the wrapper's BadRequest, a direct requests.post that ignores response.json()["ok"], or a queue worker that acks the job before checking the Telegram response. Add body["ok"] checks and a structured log line and the silence stops.

Question 3

Can I just use Python's `re.escape` to escape MarkdownV2?

Accepted Answer

No. re.escape is built for the regex grammar, not Telegram's MarkdownV2 grammar — it escapes @, :, /, ^, $, and others that MarkdownV2 leaves alone. The re.escape output reaches Telegram with foreign backslashes and triggers a different 400 (Character '\' is reserved and must be escaped). Use the explicit 18-char regex from Step 2 instead.

Question 4

How do I escape a URL inside a Telegram MarkdownV2 inline link?

Accepted Answer

Inside the parentheses of text only two characters need escaping: ) and \. The text segment outside the parens is normal text and follows the full 18-character rule. A URL like https://en.wikipedia.org/wiki/Telegram_(software) becomes https://en.wikipedia.org/wiki/Telegram_(software\) inside the parens — only the closing paren is escaped, the underscore and the opening paren stay literal.

Question 5

Do code blocks follow the same MarkdownV2 escaping rules?

Accepted Answer

No. Inside a ` inline or fenced code block, only the backtick ` and the backslash \ are reserved. Every other character — including all 16 other normal-text reserved chars — is literal. If you reuse the normal-text escape helper inside a code block, subscribers see def\ foo` with literal backslashes and your snippet looks broken.

Question 6

What's the safest way to send a MarkdownV2 message in production?

Accepted Answer

Three layers: (1) an escape_markdown_v2(text) helper imported once and applied to every user-supplied segment, (2) an HTTP wrapper that always inspects response.json()["ok"] and raises with the offending preview substring, (3) a fixture suite of awkward strings (dots, exclamations, parens-in-URL, code blocks, emoji) that runs in CI on every escape-helper or wrapper-library change. The Step 5 fixture above is a working starting point.