Prereq Check Agent Skill

Prerequisites Check

Validate that the local environment has the CLI tools and auth sessions needed to run Git-Ape skills. Print platform-specific install commands and PATH-repair guidance for anything missing or version-stale.

Quick Reference

| Property | Value |

|----------|-------|

| Best for | First-time setup, command not found triage, dev container validation |

| Required binaries | az ≥ 2.50, gh ≥ 2.0, jq ≥ 1.6, git (any) |

| Required auth | az login, gh auth login |

| Shell | bash on macOS/Linux, PowerShell 7+ on Windows |

| MCP tools | None — runs locally via shell |

| Related skills | git-ape-onboarding (next step), azure-validate (deployment-time checks) |

| Side effects | Read-only — never installs or modifies anything |

When to Use

• Before first-time onboarding (/git-ape-onboarding)
• When any Git-Ape skill fails with command not found
• When the user reports a missing binary in their prompt (e.g., az: command not found)
• After switching machines, shells, or dev containers
• When the user asks "what do I need to install?"

Rules

• Run read-only — never brew install, apt-get install, or any state-changing command. Print the commands; the user runs them.
• Trust user reports — if the user reports a tool missing, treat it as ⚠️ even when this terminal can find it (different shell, PATH, container, or machine).
• Stop at first blocking failure — do not continue to auth checks while any tool is ❌.
• Do not chain into other skills — never auto-invoke git-ape-onboarding; tell the user to run it after READY.

Steps

| # | Action | Reference |

|---|--------|-----------|

| 1 | Detect Platform — uname -s / uname -m on bash, $PSVersionTable.OS on PowerShell → macOS / Linux (apt vs dnf) / Windows (PowerShell 7+) | inline |

| 2 | Scan Prompt for Reported Missing Tools — match <tool>: command not found, command not found: <tool>, <tool> is not installed | inline |

| 3 | Run Tool Check — macOS/Linux: bash scripts/check-tools.sh · Windows: pwsh -File scripts/check-tools.ps1 | scripts/check-tools.sh, scripts/check-tools.ps1 |

| 4 | Present Status Table — pass/fail with found vs. minimum version | See Status Table |

| 5 | Show Install / PATH Repair — only for ❌ and ⚠️ entries, scoped to platform | references/install-commands.md |

| 6 | Check Auth Sessions — only if Step 4 reports all tools ✅ | See Auth Checks |

| 7 | Emit Verdict — exactly one of READY / TOOLS MISSING / REPORTED MISSING / AUTH MISSING | See Outputs |

Status Table

scripts/check-tools.sh emits TSV rows of tool<TAB>status<TAB>found<TAB>minimum. Render them as:

| Tool | Status | Found | Required |

|------|--------|-------|----------|

| az | ✅ / ⚠️ / ❌ | x.y.z | 2.50 |

| gh | ✅ / ⚠️ / ❌ | x.y.z | 2.0 |

| jq | ✅ / ⚠️ / ❌ | x.y | 1.6 |

| git | ✅ / ❌ | x.y.z | any |

Status mapping:

• OK → ✅
• OUTDATED or MISSING → ❌
• Reported missing in Step 2 but OK in this terminal → ⚠️ with note reported missing by user

Auth Checks

macOS / Linux (bash):

az account show --query "{name:name,id:id,tenantId:tenantId}" -o table 2>/dev/null \
  || echo "❌ Not logged in to Azure. Run: az login"

gh auth status 2>/dev/null \
  || echo "❌ Not logged in to GitHub. Run: gh auth login"

Windows (PowerShell 7+):

az account show --query "{name:name,id:id,tenantId:tenantId}" -o table 2>$null
if (-not $?) { Write-Output "❌ Not logged in to Azure. Run: az login" }

gh auth status 2>$null
if (-not $?) { Write-Output "❌ Not logged in to GitHub. Run: gh auth login" }

Outputs

A single chat message containing:

• Status table from Step 4.
• Install / PATH repair commands for ❌ and ⚠️ entries — pulled from references/install-commands.md, scoped to the detected platform.
• Auth status (Azure subscription + GitHub user) from Step 6, only when all tools ✅.
• Final verdict — exactly one of:
• ✅ READY — all tools installed, versions OK, auth sessions active. Render the handoff chip from ## Next so the user can click into onboarding.
• ⚠️ TOOLS MISSING — list what to install. Do not continue.
• ⚠️ REPORTED MISSING — this terminal finds the tool but the user reported it missing. Print install / PATH repair + verification block.
• ⚠️ AUTH MISSING — tools OK but az login and/or gh auth login required.

Error Handling

| Error | Cause | Fix |

|-------|-------|-----|

| az --version hangs | Stale telemetry / extension cache | az config set core.collect_telemetry=false; reinstall if persistent |

| gh auth status says "not logged into any hosts" | No GitHub session | gh auth login --web |

| az account show returns Please run 'az login' | Expired or missing session | az login (use --use-device-code in headless shells) |

| User reports missing tool but this terminal finds it | Different shell / PATH / container / machine | Treat as ⚠️ REPORTED MISSING — print install + PATH repair, do not contradict |

| jq --version starts with 1.5 | Below minimum (1.6) | Upgrade via platform package manager |

| check-tools.sh: Permission denied | Script not executable | chmod +x .github/skills/prereq-check/scripts/check-tools.sh |

| check-tools.ps1 cannot be loaded because running scripts is disabled | PowerShell execution policy | Run via pwsh -File scripts/check-tools.ps1 (bypasses script-block policy), or Set-ExecutionPolicy -Scope Process RemoteSigned |

| pwsh: command not found on Windows | PowerShell 7+ not installed | winget install Microsoft.PowerShell — Windows PowerShell 5.1 also works but ship pwsh for parity |

Constraints

Always:

• Print install commands; let the user run them
• Detect platform before printing recipes
• Honor user-reported missing tools even when this terminal finds them
• Stop at the first blocking failure
• Verify with command -v <tool> + <tool> --version after suggested fixes

Never:

• Run brew install, apt-get install, winget install, or any state-changing command
• Require git-bash on Windows — use the PowerShell script (scripts/check-tools.ps1) instead
• Auto-invoke git-ape-onboarding after a READY verdict
• Silently drop a reported-missing tool because this terminal finds it
• Continue to auth checks while any tool is ❌
• Recommend sudo on macOS (Homebrew handles non-root install)

Next

After a ✅ READY verdict, render this line verbatim so the chat surface turns it into a clickable handoff:

> Next: @Git-Ape Onboarding — or run /git-ape-onboarding to start setup.

VS Code Copilot Chat renders @AgentName mentions and /skill-name slash commands as clickable chips — the user clicks once to dispatch. Do not auto-invoke (Rule 4).

For deployment-time validation of an Azure project, use azure-validate instead.