slack-gif-creator Skill for Claude: Make Animated GIFs for Slack

Makes Claude build animated GIFs sized for Slack emoji and messages, using bundled Python helpers and a validator.

Installs: 77.4K; on skills.sh
Stars: 186.4K; on GitHub
Files: 6; besides SKILL.md
Updated: Oct 2026; last repo commit

slack-gif-creator makes Claude draw and animate a GIF from a request like "make me a GIF of X doing Y for Slack". It follows Slack's size rules (128x128 for emoji, 480x480 for messages), builds frames with Python and the Pillow library, and checks the result with a validator.

It needs Python with a few packages, and it runs the bundled helper code to write the GIF file. If you upload an image, it can use it directly or as a style guide.

Good for

Slack users who want a custom animated emoji or reaction GIF
Team admins who need GIFs that pass Slack's size limits
Developers who want a small PIL and Python GIF toolkit for Claude

Install slack-gif-creator

Claude Code

Copy this prompt.

Install the slack-gif-creator skill in Claude Code. Run this command:

npx skills add anthropics/skills --skill slack-gif-creator -a claude-code

Then check that it loaded and tell me how to use it.

2
Paste it into Claude Code. It shows the change and asks before running it.

Requires Node.js, Python with pillow, imageio, numpy.

The plugin route installs all 12 skills in the example-skills plugin, not only this one. Before first use, install the Python packages: pip install pillow imageio numpy (the bundled requirements.txt also lists imageio-ffmpeg).

From the vendor's docs. Source.

What's in the skill

When it loads

Knowledge and utilities for creating animated GIFs optimized for Slack. Provides constraints, validation tools, and animation concepts. Use when users request animated GIFs for Slack like "make me a GIF of X doing Y for Slack."

Sections in SKILL.md

Slack Requirements
Core Workflow
Drawing Graphics
Working with User-Uploaded Images
Drawing from Scratch
Making Graphics Look Good
Available Utilities
GIFBuilder (core.gif_builder)
Validators (core.validators)
Easing Functions (core.easing)
Frame Helpers (core.frame_composer)
Animation Concepts
Shake/Vibrate
Pulse/Heartbeat
Bounce
Spin/Rotate

Key facts

Author: Anthropic
Repo: anthropics/skills
License: Apache License 2.0, per the LICENSE.txt in the skill folder
Installs on skills.sh: 77,402 (Nov 2, 2026)
GitHub stars (whole repo): 186,362 (Nov 2, 2026)
Last commit to the repo: Oct 28, 2026
skills.sh audits: Gen Agent Trust Hub pass, Socket pass, Snyk pass
Skill folder: 7 files: SKILL.md, LICENSE.txt, requirements.txt and 4 Python modules in core/ (counted from the GitHub folder)
Needs: Python packages: pillow, imageio, numpy (SKILL.md) and imageio-ffmpeg (requirements.txt)
Repo note: The README says the repo's skills are for demonstration and educational use; test them before relying on them

What it includes

Sizes and limits the GIF must meet
Emoji GIFs 128x128 (recommended), message GIFs 480x480, 10 to 30 FPS, 48 to 128 colors, and under 3 seconds for emoji.
Slack requirements
Collects frames and saves an optimized GIF
add_frame and add_frames take Pillow images. save() takes num_colors, optimize_for_emoji and remove_duplicates.
Runs code · GIFBuilder (core/gif_builder.py)
Checks a GIF against Slack's limits
validate_gif returns a pass flag and details. is_slack_ready is a quick yes or no.
Runs code · Validators (core/validators.py)
Smooth motion curves for animation
Options: linear, ease_in, ease_out, ease_in_out, bounce_out, elastic_out and back_out.
Runs code · Easing (core/easing.py)
Blank frames, gradients, circles, text and stars
Helpers named create_blank_frame, create_gradient_background, draw_circle, draw_text and draw_star.
Runs code · Frame helpers (core/frame_composer.py)
Recipes for 8 common effects
Shake, pulse or heartbeat, bounce, spin, fade, slide, zoom and particle burst.
Animation concepts
Uses your picture directly or as inspiration
Claude asks itself which you meant, then loads the file with Pillow.
Files · Uploaded images
Shrinks a GIF, only when you ask
Fewer frames, fewer colors, smaller size, duplicate removal and emoji mode.
Optimization strategies

From the official docs

Permissions

Medium risk

The skill makes Claude run bundled Python code and write GIF files, and it asks for a few Python packages. Install the packages in a virtual environment and approve each command.

What it can do

Read your data
Create and change things
Delete things
Read-only mode

Watch out for

It runs bundled Python code
Claude imports the core modules to build and check GIFs. Read the four files in core/ if you want to know what runs.
It asks you to pip install packages
The SKILL.md lists pillow, imageio and numpy, and requirements.txt adds imageio-ffmpeg. Install them in a virtual environment.
It writes GIF files to disk
Output files such as out.gif are saved in the working folder. Check the path before you share them.
The plugin route installs 12 skills
The README's plugin install adds the whole example-skills plugin, which lists slack-gif-creator among 12 skills. Use the per-skill command in the install box to take only this one.

Technical details

Talks to	pip install pillow imageio numpy fetches packages from your package index

Questions

How do I install slack-gif-creator?

Use the install box above. The skill lives in Anthropic's skills repo, whose README also documents registering the repo as a Claude Code plugin marketplace. Install the Python packages the skill lists before first use.

Does slack-gif-creator work in the Claude app or Codex?

The anthropics/skills README says the repo's example skills are already available to paid plans in Claude.ai, but it does not list which skills. Codex is not mentioned in that README.

What do I need installed?

Python with pillow, imageio and numpy, which the SKILL.md lists. The bundled requirements.txt also lists imageio-ffmpeg. No API key is named.

Can it turn my own image into a GIF?

Yes. The skill says that if you upload an image Claude should decide whether you want it used directly, such as "animate this", or as inspiration, and then load it with Pillow.

Will it use emoji fonts or ready-made art?

No. The skill says not to use emoji fonts and says it ships no pre-made graphics. Claude draws shapes from scratch with Pillow.

Is slack-gif-creator safe?

The skill bundles Python code that Claude runs to make and check GIF files, and it asks you to pip install packages. Read the code in core/ if you want to know what runs, and approve commands as they come.

Information

updated Nov 2, 2026

Repository: anthropics/skills
Folder: skills/slack-gif-creator

anthropics/skills skills.sh

Sources

Docs, issue trackers and discussions this page is built from.

Show all 6

anthropics/skills README · github.com
anthropics/skills marketplace.json · github.com
skills CLI commands · github.com
slack-gif-creator SKILL.md · github.com
slack-gif-creator on skills.sh · skills.sh
anthropics/skills · github.com