caption-writer-sms

caption-writer-sms is a skill for Claude Code, Codex from blacktwist/social-media-skills. It costs 168 tokens per session (4,966 once invoked), scanned A, original, MIT.

A set of instructions for writing text that accompanies images and videos on platforms such as Instagram, TikTok, YouTube, Pinterest, and Facebook. It treats the visual as the main content and the caption as supporting text.

In plain words
What is it for?
Use it to write captions for photos, videos, Reels, TikToks, pins, YouTube videos, and related visual posts.
Why use it?
It helps match the wording to the platform and the type of visual, instead of using a generic post format.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to write captions for photos, videos, Reels, TikToks, pins, YouTube videos, and related visual posts.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/blacktwist/social-media-skills/caption-writer-sms
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add blacktwist/social-media-skills --skill caption-writer-sms
Clone the repo
git clone --depth 1 https://github.com/blacktwist/social-media-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for caption-writer-sms

README.md
[![agentmods](https://agentmods.dev/badge/skills/blacktwist/social-media-skills/caption-writer-sms/github.svg)](https://agentmods.dev/skills/blacktwist/social-media-skills/caption-writer-sms)
Your own site
<a href="https://agentmods.dev/skills/blacktwist/social-media-skills/caption-writer-sms"><img src="https://agentmods.dev/badge/skills/blacktwist/social-media-skills/caption-writer-sms/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for caption-writer-sms

Your own site · 80×15
<a href="https://agentmods.dev/skills/blacktwist/social-media-skills/caption-writer-sms"><img src="https://agentmods.dev/badge/skills/blacktwist/social-media-skills/caption-writer-sms.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 168 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,966 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 1 May 2026
  • Snyk pass 1 May 2026
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00168 $0.04966
Opus 5 $0.00084 $0.02483
Sonnet 5 $0.00034 $0.00993
Haiku 4.5 $0.00017 $0.00497

Measured 13d ago against content hash d159f75b4b55, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

caption-writer-sms scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 13d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/caption-writer-sms/SKILL.md · 397 lines

How it starts

The opening of the file, as written. The whole thing — 397 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Caption Writer

When to Use

  • User asks to write a caption for an image, video, Reel, Short, or pin
  • User mentions "Instagram caption," "IG caption," "Reels caption," or "TikTok caption"
  • User mentions "Pinterest description," "pin caption," "Facebook caption," or "YouTube description"
  • User wants a YouTube title, video description, Shorts caption, or Community post text
  • User shares a visual asset (photo, video, graphic) and wants supporting copy
  • User wants to publish a Reel, TikTok, carousel post, pin, or YouTube video and needs the words that go with it
  • User says "what should I write under this," "caption this," or "give me a description for this"

This skill is for visual-first platforms where the image or video is the primary content and the caption supports it. For text-first platforms (LinkedIn, Twitter/X, Threads, Bluesky), use post-writer-sms instead.

Role

You are an expert caption writer who knows that on visual platforms, the visual stops the scroll and the caption closes the loop. You write captions that earn the tap on "more," reward the pause, and convert lurkers into savers, sharers, and followers. You understand that each platform — Facebook, Instagram, TikTok, Pinterest — has its own grammar, hook mechanics, hashtag rules, and search behavior, and you write to those rules instead of fighting them.

Context Check

Before writing, read .agents/social-media-context-sms.md to understand the user's voice, content pillars, target audience, and example captions if provided. Match vocabulary, sentence rhythm, emoji habits, and emotional register.

If the file does not exist, say:

"I don't see a social media context file yet. Run the social-media-context-sms skill first to capture your voice and preferences — it takes about 5 minutes and makes every caption I write sound like you."

If the user wants to proceed without it, use neutral defaults and flag the limitation.


Input Gathering

Ask only for what the user has not already provided:

Read the full file on GitHub · 397 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 13d ago First seen · 397 lines · 168 tokens per session scan A d159f75b4b55

Subscribe to this mod's changes

caption-writer-sms is a skill published in the GitHub repository blacktwist/social-media-skills (498 stars, last pushed 4mo ago), licensed MIT. It adds 168 tokens to every session and 4,966 once invoked, about $0.0008 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

humanizer-ru

A Russian-text editor that removes bureaucratic wording, filler, copied chatbot patterns and signs of AI writing while keeping facts and examples.

smixs/humanizer-ru · 263 tokens

sansheng-write

A Chinese-language writing workflow creates, edits, formats, and repurposes long articles, including public-account posts and social-media versions.

sanshengai/sansheng-write · 113 tokens

sfumatoai-writing-skill

Turn keywords, long text, articles, URLs, files, screenshots, or mixed media into verified Xiaohongshu knowledge-explainer image posts for AI-interested beginners. Use when Codex must analyze the input instead of blindly summarizing it, choose the strongest topic, research ambiguous or technical claims with…

sunshine-lang/sfumatoAI-writing-skill · 134 tokens

publisher-wechatsync

A publishing workflow that sends a finished Markdown blog draft to several Chinese content platforms through the Wechatsync command-line tool.

xiaomoBoy/claude-writing-skills · 90 tokens

research-collector

A research workflow that collects YouTube videos and web articles into a NotebookLM notebook, then saves analysis results as Markdown.

xiaomoBoy/claude-writing-skills · 98 tokens

yt-dlp-direct

Use when the user wants to download or inspect online audio/video directly with the installed yt-dlp CLI. Best for single videos, playlists, audio extraction, subtitle download, format inspection, output templates, cookies-from-browser flows, and practical troubleshooting of yt-dlp commands.

xiaomoBoy/claude-writing-skills · 63 tokens