How do I install the Stegg CLI skill?

Run npx skillmds@latest add elder-plinius/stegg-cli in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Stegg CLI safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Stegg CLI?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Stegg CLI free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Stegg CLI?

elder-plinius (@elder-plinius) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Stegg CLI by elder-plinius — Agent Skill

Name: Stegg CLI
Author: elder-plinius

Stegg CLI

Subprocess CLI for ST3GG steganography — encode/decode, steganalysis, PNG chunk/EXIF injection, and AI red-team payloads. Runs as subprocess so output stays out of context. Use when hiding data in images, analyzing images for hidden content, injecting metadata, crafting steganographic PoCs, or detecting steganographic content. Triggers on stegg, steganography, steg, LSB, hide data in image, hidden data, steganalysis.

File contents

ST3GG CLI

Subprocess steganography CLI. Output stays out of LLM context — call via python3 stegg_cli.py <command>. All output is JSON.

This is the primary interface for steganography operations. Prefer this over the MCP server for routine use (zero context cost). Fall back to MCP tools when you need results inline.

Commands

encode        -i IMAGE [-t TEXT|-f FILE] [-o OUT] [--channels C] [--bits N] [--password P]
decode        -i IMAGE [-o OUT] [--no-auto] [--channels C] [--bits N] [--password P]
analyze       IMAGE [--full]
detect        IMAGE
capacity      IMAGE [--channels C] [--bits N]
inject-chunk  -i IMAGE -o OUT --text TEXT [--type tEXt] [--keyword Comment]
read-chunks   IMAGE
inject-exif   -i IMAGE -o OUT [--comment C] [--author A] [--custom-fields JSON]
inject-name   [--template T] [--channels C] [--count N]
templates
analysis-tool IMAGE ACTION
list-tools
crypto-status

Quick Reference

Encode + Verify + Decode

# Hide text
python3 stegg_cli.py encode -i carrier.png -t "secret message" -o stegged.png
# Always verify roundtrip after encoding
python3 stegg_cli.py decode -i stegged.png

# Hide file with encryption
python3 stegg_cli.py encode -i carrier.png -f payload.bin -o stegged.png --password s3cret
python3 stegg_cli.py decode -i stegged.png --password s3cret

# Decode with manual config (non-interleaved strategies)
python3 stegg_cli.py decode -i stegged.png --no-auto --strategy sequential

Analyze + Detect

# Quick header check
python3 stegg_cli.py detect suspect.png

# Chi-square anomaly analysis
python3 stegg_cli.py analyze suspect.png

# Full 264-function sweep (PNG only)
python3 stegg_cli.py analyze suspect.png --full

# Specific analysis function
python3 stegg_cli.py analysis-tool suspect.png rs_analysis
python3 stegg_cli.py analysis-tool suspect.png sample_pairs_analysis

Metadata Injection

# PNG chunk
python3 stegg_cli.py inject-chunk -i image.png -o out.png --text "hidden metadata"

# Private chunk type
python3 stegg_cli.py inject-chunk -i image.png -o out.png --type stEg --text "private"

# EXIF fields
python3 stegg_cli.py inject-exif -i image.png -o out.png --comment "payload" --author "red-team"

# Read chunks
python3 stegg_cli.py read-chunks image.png

AI Red Team

# Generate injection filenames
python3 stegg_cli.py inject-name --template claude_decoder --channels R --count 3

# List jailbreak templates
python3 stegg_cli.py templates

Key Constraints

Use interleaved strategy (default) — only strategy with auto-detect on decode
spread and randomized have upstream decode bugs
sequential works but needs --no-auto on decode
All output is JSON; errors: {"error": "..."} with exit code 1
Always check for error key in JSON output before proceeding in multi-step operations
Always verify encode with decode before distributing stegged images

Installation

pip install stegg
# CLI is available as stegg-cli, or:
python3 /path/to/st3gg/stegg_cli.py <command>

---name: stegg-clidescription: Subprocess CLI for ST3GG steganography — encode/decode, steganalysis, PNG chunk/EXIF injection, and AI red-team payloads. Runs as subprocess so output stays out of context. Use when hiding data in images, analyzing images for hidden content, injecting metadata, crafting steganographic PoCs, or detecting steganographic content. Triggers on stegg, steganography, steg, LSB, hide data in image, hidden data, steganalysis.---# ST3GG CLISubprocess steganography CLI. Output stays out of LLM context — call via `python3 stegg_cli.py <command>`. All output is JSON.**This is the primary interface for steganography operations.** Prefer this over the MCP server for routine use (zero context cost). Fall back to MCP tools when you need results inline.## Commands```encode -i IMAGE [-t TEXT|-f FILE] [-o OUT] [--channels C] [--bits N] [--password P]decode -i IMAGE [-o OUT] [--no-auto] [--channels C] [--bits N] [--password P]analyze IMAGE [--full]detect IMAGEcapacity IMAGE [--channels C] [--bits N]inject-chunk -i IMAGE -o OUT --text TEXT [--type tEXt] [--keyword Comment]read-chunks IMAGEinject-exif -i IMAGE -o OUT [--comment C] [--author A] [--custom-fields JSON]inject-name [--template T] [--channels C] [--count N]templatesanalysis-tool IMAGE ACTIONlist-toolscrypto-status```## Quick Reference### Encode + Verify + Decode```bash# Hide textpython3 stegg_cli.py encode -i carrier.png -t "secret message" -o stegged.png# Always verify roundtrip after encodingpython3 stegg_cli.py decode -i stegged.png# Hide file with encryptionpython3 stegg_cli.py encode -i carrier.png -f payload.bin -o stegged.png --password s3cretpython3 stegg_cli.py decode -i stegged.png --password s3cret# Decode with manual config (non-interleaved strategies)python3 stegg_cli.py decode -i stegged.png --no-auto --strategy sequential```### Analyze + Detect```bash# Quick header checkpython3 stegg_cli.py detect suspect.png# Chi-square anomaly analysispython3 stegg_cli.py analyze suspect.png# Full 264-function sweep (PNG only)python3 stegg_cli.py analyze suspect.png --full# Specific analysis functionpython3 stegg_cli.py analysis-tool suspect.png rs_analysispython3 stegg_cli.py analysis-tool suspect.png sample_pairs_analysis```### Metadata Injection```bash# PNG chunkpython3 stegg_cli.py inject-chunk -i image.png -o out.png --text "hidden metadata"# Private chunk typepython3 stegg_cli.py inject-chunk -i image.png -o out.png --type stEg --text "private"# EXIF fieldspython3 stegg_cli.py inject-exif -i image.png -o out.png --comment "payload" --author "red-team"# Read chunkspython3 stegg_cli.py read-chunks image.png```### AI Red Team```bash# Generate injection filenamespython3 stegg_cli.py inject-name --template claude_decoder --channels R --count 3# List jailbreak templatespython3 stegg_cli.py templates```## Key Constraints- **Use `interleaved` strategy** (default) — only strategy with auto-detect on decode- `spread` and `randomized` have upstream decode bugs- `sequential` works but needs `--no-auto` on decode- All output is JSON; errors: `{"error": "..."}` with exit code 1- **Always check for `error` key** in JSON output before proceeding in multi-step operations- **Always verify encode with decode** before distributing stegged images## Installation```bashpip install stegg# CLI is available as stegg-cli, or:python3 /path/to/st3gg/stegg_cli.py <command>```

Frequently asked questions