--- name: whatsapp-text-formatting source: https://app.decimal.ai/s/whatsapp-text-formatting@1/SKILL.md source_sha256: 16265d583fd9 --- # WhatsApp text formatting ## Contract Enforces WhatsApp's native text markup on every message you send into a WhatsApp chat: single-character emphasis delimiters, bare auto-linked URLs, and no heading syntax. Apply whenever the reply is destined for WhatsApp (a 1:1 chat or a group). The base model's default is standard Markdown, which WhatsApp does NOT render — doubled delimiters and `[text](url)` links arrive as literal characters. ## Rules WhatsApp emphasis uses ONE delimiter character on each side, not two. This is the whole point: the form is deliberately different from Markdown. 1. **Bold** — wrap the text in a SINGLE asterisk: `*text*`. Never `**text**`. A doubled asterisk is NOT bold on WhatsApp; it renders as a literal `*` plus italic plus a literal `*`. 2. **Italic** — wrap the text in a SINGLE underscore: `_text_`. Never `*text*` for italic (that is bold here) and never `__text__` (doubled underscores render literally). 3. **Strikethrough** — wrap the text in a SINGLE tilde: `~text~`. Never `~~text~~`; the doubled-tilde Markdown form renders as literal tildes around the words. 4. **Inline monospace** — wrap in single backticks: `` `text` ``. Use it for short code, identifiers, commands, or values that must not be auto-formatted. 5. **Monospace block** — wrap a multi-line snippet in triple backticks on their own lines. Use it for code, logs, or anything where line breaks and spacing must be preserved. 6. **Links — paste the BARE URL.** Write `https://example.com` on its own and WhatsApp auto-links it. NEVER use Markdown link syntax `[label](https://example.com)` — WhatsApp does not parse it, so the recipient sees the literal characters `[label](https://example.com)` and gets no clickable link. If you want a label, put the words and the bare URL near each other. 7. **No headings.** WhatsApp has no `#`/`##` heading syntax. A line that starts with `# Title` shows the literal `#`. To make a heading-like line, BOLD it instead: a bold title line. 8. **Delimiter placement.** The delimiter must hug the text with no inner spaces — the run must start and end against a non-space character. Put whitespace (or the message start/end) on the OUTSIDE of the delimiters so WhatsApp recognizes the span. 9. **Combining styles** — nest single delimiters: bold + italic is one asterisk pair wrapping one underscore pair. Keep every delimiter balanced (one opener, one closer). 10. **Lists & quotes (optional).** A line beginning `- ` (or `* `) becomes a bullet; `1. ` becomes a numbered item; `> ` becomes a quote. These match Markdown and are safe to use; the emphasis markup inside them still follows rules 1-3. ## Worked examples One BEFORE (the Markdown the base defaults to) → AFTER (the WhatsApp-native form). **Bold — server notice.** Tell the channel maintenance is over, "resolved" emphasized. ``` BEFORE: Maintenance is **resolved** — all systems are back online. AFTER: Maintenance is *resolved* — all systems are back online. ``` Double asterisk → single asterisk. **Italic — a soft caveat.** ``` BEFORE: We'll aim for Friday, *though that may slip*. AFTER: We'll aim for Friday, _though that may slip_. ``` Markdown italic-by-asterisk → WhatsApp italic-by-underscore (asterisks would render bold). **Strikethrough — a corrected figure.** ``` BEFORE: The fee is ~~$40~~ now $25. AFTER: The fee is ~$40~ now $25. ``` Double tilde → single tilde. **Link — share a page.** ``` BEFORE: Sign up here: [the registration page](https://acme.example/signup) AFTER: Sign up here: https://acme.example/signup ``` Markdown link (renders as literal text on WhatsApp) → bare auto-linked URL. **Heading — a titled announcement.** ``` BEFORE: # Release 2.0 is live New dashboard and faster sync. AFTER: *Release 2.0 is live* New dashboard and faster sync. ``` `#` heading (shows a literal `#`) → a bold title line. **Combined — bold name + italic note.** ``` BEFORE: **Priya** will lead the call *(bring your notes)*. AFTER: *Priya* will lead the call _(bring your notes)_. ``` Each style switched to its single-character WhatsApp delimiter. **Monospace block — a snippet.** ```` BEFORE: Run `npm run deploy` then check the log. (inline is fine) AFTER: Run `npm run deploy` then check the log. ```` Inline single backticks are the same on both; reserve triple backticks for multi-line blocks. ## Edge cases & exceptions - **Asterisk that is NOT emphasis** (a math `2 * 3`, a literal bullet glyph in prose): leave a space on at least one inner side so WhatsApp does not treat it as a delimiter, e.g. `2 * 3`. - **Underscores inside a URL or identifier** (`my_file.py`, a query string) are not italic — WhatsApp only treats `_x_` as italic when the underscores bound a word run with outer whitespace; inside a token they stay literal. Don't try to "fix" them. - **A delimiter with an inner space** (`* text *`) does NOT render — WhatsApp ignores it and shows the literal asterisks. Always hug the text: `*text*`. - **Want a literal `*`, `_`, or `~`** with no formatting: separate it from word characters with a space, or rephrase; WhatsApp has no backslash escape. - **Long code / config**: use the triple-backtick block, not inline backticks, so wrapping and indentation survive. - **A label you really want on a link**: WhatsApp can't hide a URL behind link text — put the human words and then the bare URL; never the `[label](url)` form. - **Mixed Markdown habits**: `**bold** _italic_` is half-wrong — the bold half won't render. Convert every emphasis run, not just some. ## Do / Don't - DON'T write `**bold**`. ALWAYS write `*bold*` (single asterisk). - DON'T write `~~strike~~`. ALWAYS write `~strike~` (single tilde). - DON'T use `*text*` for italic. ALWAYS use `_text_` (asterisks are bold here). - DON'T write `[label](url)`. ALWAYS paste the bare URL. - DON'T start a line with `#` for a heading. ALWAYS use a bold line instead. - DON'T put spaces just inside the delimiters (`* x *`). ALWAYS hug the text (`*x*`). - DON'T leave some emphasis in Markdown form. ALWAYS convert every run to single-delimiter form. ## Common mistakes (the base model's wrong defaults) - Emitting `**bold**` out of Markdown habit — the most common failure; it renders wrong. - Using `~~strikethrough~~` (GitHub-flavored Markdown) instead of single `~`. - Reaching for `[text](url)` links, which WhatsApp shows as raw characters with no link. - Opening a message with a `#`/`##` heading line that displays a literal `#`. - Using `*emphasis*` meaning italic — on WhatsApp that is bold, so the intent flips. - Padding delimiters with inner spaces so nothing renders at all. ## Quick checklist - [ ] Bold is a SINGLE asterisk `*x*`, never `**x**`. - [ ] Italic is a SINGLE underscore `_x_`, never `*x*` or `__x__`. - [ ] Strikethrough is a SINGLE tilde `~x~`, never `~~x~~`. - [ ] Links are BARE URLs, never `[label](url)`. - [ ] No `#`/`##` heading lines — a bold line stands in for a heading. - [ ] Delimiters hug the text (no inner spaces); every pair is balanced.