Files

SKILL.mdagentsreferencesscripts

Install

Install the containing plugin

/plugin install shared-skills@llm-skills

Invoke this skill after installation

/shared-skills:ssh-client

Download ssh-client-skill.zip

This skill is bundled inside shared-skills. Install the plugin once, then Claude Code can use any of its included skills. Browse the full plugin repository at github.com/alisonaquinas/llm-shared-skills.

SKILL.md

name: ssh-client description: Establish secure SSH connections with strict host verification and key management. Use when the agent needs remote access, Git-over-SSH operations, or key pair validation.

ssh (client)

Secure remote access with strict host key verification and known_hosts management.

Prerequisite Check

Run this before proposing remote access steps:

command -v ssh >/dev/null 2>&1 || ssh -V

If ssh is missing, surface that first and point to scripts/install.sh or scripts/install.ps1. Do not suggest insecure fallbacks such as disabling host verification or using plaintext remote shells.

Quick Start

Verify ssh is available: ssh -V or man ssh
Establish the command surface: man ssh or ssh -h
Start with connectivity check: ssh -o BatchMode=yes -o StrictHostKeyChecking=accept-new host

Intent Router

Load only the reference file needed for the active request.

references/install-and-setup.md — Installing OpenSSH on macOS, Linux, Windows
references/cheatsheet.md — Common options, authentication, host key management
references/advanced-usage.md — Strict verification, key forwarding, config files
references/troubleshooting.md — Authentication errors, host key issues, permission problems

Core Workflow

Verify ssh is available: ssh -V
Capture host keys before first connection: ssh-keyscan host >> ~/.ssh/known_hosts
Use strict host checking: ssh -o StrictHostKeyChecking=accept-new user@host
Debug with verbose logging: ssh -vvv user@host

Quick Command Reference

ssh -V                                 # Check version
ssh-keyscan -p 22 github.com >> ~/.ssh/known_hosts  # Capture host keys
ssh -o StrictHostKeyChecking=accept-new user@host   # Connect with verification
ssh -o StrictHostKeyChecking=yes user@host          # Strict verification
ssh -vvv user@host                     # Verbose debugging (3x)
ssh-keygen -R hostname                 # Remove hostname from known_hosts
man ssh                                # Full manual

# Probe connectivity without interactive password prompts
ssh -o BatchMode=yes -o StrictHostKeyChecking=accept-new user@host true

# Inspect the host key before a first connection
ssh-keyscan -p 22 host | tee -a ~/.ssh/known_hosts

Safety Notes

Area	Guardrail
Host key verification	Always use StrictHostKeyChecking=accept-new or yes. Never use no. Prevents MITM attacks.
Private key permissions	Restrict to 600 (chmod 600 ~/.ssh/id_rsa). SSH refuses keys with wrong permissions.
known_hosts management	Verify host keys before adding. Use ssh-keyscan carefully from trusted networks only.
Key passphrase	Protect private keys with strong passphrases. Use ssh-agent for convenient access.
Agent forwarding	Be cautious with -A. Forwarding agent is high-risk on untrusted hosts.
Config file	Restrict permissions (chmod 600 ~/.ssh/config). May contain sensitive information.

Recovery note: if the runtime has no ssh client, stop at install guidance. Do not route around that by suggesting telnet-like substitutes or StrictHostKeyChecking=no.

Source Policy

Treat the installed ssh behavior and man ssh as runtime truth.
Use OpenSSH documentation for security best practices.

Resource Index

scripts/install.sh — Install OpenSSH on macOS or Linux.
scripts/install.ps1 — Install OpenSSH on Windows or any platform via PowerShell.