The X agent skill

Eleven Claude skills that run an X account. Free, MIT, no signup, no API key, nothing to connect.

They write your posts, comment on other people's threads, handle your replies, fix your profile and plan your week. And one of them is the virality skill: it finds the posts that are actually outperforming in your niche, breaks each one down into hook, structure and format, and recreates the winners in your voice, for your audience.

Under the skills are nine tools that actually run. One counts a post the way X counts it (links are 23, emoji are 2). One scores your first line before you post it. One cuts a draft into a thread that fits. One reads X's own published ranking code and tells you what it rewards this week. One reads your analytics export and tells you what worked, with the sample size on every claim.

Nothing is posted until you approve it. These skills write. You post.

Install

Paste this into Claude:

https://github.com/Jakeschincariol/x-agent-skill

Install this skill, then confirm /x-post works.

Or do it yourself, in Claude Code:

git clone https://github.com/Jakeschincariol/x-agent-skill.git
cp -r x-agent-skill/skills/x-* ~/.claude/skills/

Or as a plugin:

/plugin marketplace add Jakeschincariol/x-agent-skill
/plugin install x-agent

Project-local instead of global: copy the same folders into your repo's .claude/skills/. No Claude Code at all? Paste any single SKILL.md at the top of a chat and it runs as a mode. You lose the Python tools, which is most of the point of /x-post, /x-viral and /x-human, but the rest works.

Then spend ten minutes on templates/voice.md. Copy it to ~/.claude/x/voice.md and fill it in, or paste five of your own posts into Claude and say "write my voice.md from these". Every skill reads that file. Skip it and everything comes out sounding like everyone else on the timeline.

The eleven

The nine tools

Every one runs on a clean Python 3 with no dependencies. Seven never touch the network. pull.py calls X's documented oEmbed API and weights.py reads a public GitHub file; neither needs an account or a key.

python3 skills/x-post/count.py post.txt                   # X's weighted count + six lints
python3 skills/x-post/hookscore.py hooks.txt              # score and rank first lines, name the formula
python3 skills/x-thread/thread.py draft.txt --number      # cut a draft into a thread that fits
python3 skills/x-human/humanize.py draft.txt --report     # strip the fingerprint
python3 skills/x-human/detect.py before.txt after.txt     # five-check panel, before and after
python3 skills/x-viral/pull.py urls.txt > swipe.tsv       # post URLs you picked -> text, format, date
python3 skills/x-viral/swipe.py swipe.tsv                 # outliers, broken down, as a swipe file
python3 skills/x-audit/audit.py analytics.csv             # what worked, with n on every claim
python3 skills/x-plan/weights.py                          # what X's ranker rewards, live from X's code

Counting the way X counts

X does not count characters. It counts weighted characters: every link is 23 however long it is, every emoji is 2 (a family emoji built from seven code points is still 2), Chinese, Japanese and Korean are 2, and "…" is 2, which is more than the three dots it replaces. count.py implements those rules, then draws the post the way the timeline shows it:

  WHAT FITS
  +------------------------------------------------------+
  | Most people use AI to post more. I used it to post   |
  | less.                                                |
  |                                                      |
  | In March I cut from 3 posts a day to 1. Followers    |
  | went from 2,100 to 6,800 by August.                  |
  |                                                      |
  | The system: one idea a day, drafted with Claude, cut |
  | in half by me, and I'm there for the first hour of   |
  | replies.                                             |
  |                                                      |
  | Showing up beats post                                |
  +------------------------------------ cut here, 4 over +

  FAIL  LENGTH      284 / 280, 4 over. X will not let you post it.
  PASS  FIRST LINE  56 characters, reads in one glance
  PASS  LINKS       none
  PASS  HASHTAGS    0
  PASS  MENTIONS    0
  PASS  ENDING      no reflex bait

With --premium the limit is 25,000 and the box shows where the timeline cuts a long post to "Show more", at about 280. It also flags an @mention past that point, because X does not notify it.

The hook

On X the first line is not the start of the post. It is most of the post. hookscore.py scores it on five properties (length, specificity, stakes, whether the payoff is up front, who it is aimed at), flags the dealbreakers, and names which of the 21 formulas it uses:

HOOK RANKING
==============================================================================
-> 100.0 STRONG  Nobody tells you your first 1,000 followers come from rep...
        #6 Nobody Tells You  ·  weakest: LENGTH (100)
    78.4 STRONG  I posted every day for 90 days. Here's what actually move...
        #2 Number Reveal  ·  weakest: FRONTLOAD (70)
    52.2 OK      The hottest new marketing hire is a skill file.
        #7 The Hottest New  ·  weakest: SPECIFICITY (15)
    36.2 WEAK    Hey guys, here are some thoughts on growing on X
        #21 The One-Liner  ·  weakest: STAKES (20)
        dealbreaker: Greeting. Nobody opened X to be greeted.
     4.8 WEAK    A thread 🧵
        #16 Thread Promise  ·  weakest: FRONTLOAD (0)
        dealbreaker: Opens on the word "thread". That is packaging. Put the
                     payoff in line 1 and let X's own UI say it is a thread.

Every formula in hooks.json carries a template, a filled example, what it is for, how it usually gets ruined, and a regex, so the same 21 names describe a hook you are writing and a hook you found in someone else's feed. That is what lets /x-viral say "the top third of your niche is The Hottest New and Field Report" instead of "posts that did well".

The virality engine

python3 skills/x-viral/pull.py urls.txt > swipe.tsv
# fill in the views column from the posts, they are public on every post
python3 skills/x-viral/swipe.py swipe.tsv --out ~/.claude/x/swipe.md

Raw numbers are not evidence. An account with 900,000 followers doing 400,000 views had an ordinary Tuesday; an account with 6,000 doing the same found something copyable. So swipe.py ranks on the outlier multiple, each post's views over its own account's median, computed from the 10 to 15 posts you collected per account. Accounts with too few posts are skipped instead of ranked on noise. Then each post gets broken down:

• hook: which of the 21 formulas, and its score
• structure: one line, one paragraph, short lines, a list, a long post, a thread
• format: text, media, link, long

It compares the top third with the bottom third on all three, lists the hooks it could not classify (read those, they are where a new formula is hiding) and writes a swipe file with the reusable shape of each winner. /x-viral then recreates the top three in your voice: the found post's structure, none of its words.

What X rewards, from X

X open-sourced its current recommendation system in January 2026 and has published the production ranking weights in it since August. They move: two of them changed in the week this pack was written. So weights.py reads the file live and prints it with the date of its last change:

X FOR YOU RANKER  ·  action weights  ·  live from GitHub, last changed 2026-09-29 (commit a707cc2)
==============================================================================
REWARDED                                  weight   vs a like
  share by copying the link                     20     40.0x
  + added to a reply between mutuals            15     30.0x
  reply                                          5     10.0x
  share by DM                                    5     10.0x
  quote                                          5     10.0x
  follow the author                              4