gco-2nd
Get a second opinion from GitHub Copilot CLI on a plan or approach. Use when: (1) Planning phase of /x-as-pr or /x-wt-teams to validate the approach, (2) User says 'gco 2nd', 'copilot 2nd', or 'copilot opinion', (3) Wanting an alternative perspective before committing to a plan.
Best use case
gco-2nd is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
Get a second opinion from GitHub Copilot CLI on a plan or approach. Use when: (1) Planning phase of /x-as-pr or /x-wt-teams to validate the approach, (2) User says 'gco 2nd', 'copilot 2nd', or 'copilot opinion', (3) Wanting an alternative perspective before committing to a plan.
Teams using gco-2nd should expect a more consistent output, faster repeated execution, less prompt rewriting.
When to use this skill
- You want a reusable workflow that can be run more than once with consistent structure.
When not to use this skill
- You only need a quick one-off answer and do not need a reusable workflow.
- You cannot install or maintain the underlying files, dependencies, or repository context.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/gco-2nd/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How gco-2nd Compares
| Feature / Agent | gco-2nd | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
Get a second opinion from GitHub Copilot CLI on a plan or approach. Use when: (1) Planning phase of /x-as-pr or /x-wt-teams to validate the approach, (2) User says 'gco 2nd', 'copilot 2nd', or 'copilot opinion', (3) Wanting an alternative perspective before committing to a plan.
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
SKILL.md Source
# GCO 2nd Opinion
Get a second opinion from GitHub Copilot CLI on a plan, approach, or codebase exploration.
## Process
### Step 0: Pre-flight Rate Limit Check
Before doing anything, check if Copilot is currently in degraded mode:
```bash
RATE_CHECK=$(node $HOME/.claude/scripts/gco-rate-limit.js check 2>&1)
```
If the output starts with `degraded:`, **notify the user** that Copilot is in low-cost mode (auto-downgraded model) but **proceed with Copilot anyway** — it is still usable. Do NOT skip.
### Step 1: Build Context Prompt
Construct a prompt that includes:
- The current plan or approach being considered
- Key files or areas of the codebase involved
- Specific questions or concerns
```
You are reviewing a development plan. Provide a second opinion.
## Context
<what the project is, what repo we're in>
## Current Plan
<the plan or approach being considered>
## Questions
1. Are there any risks, edge cases, or issues with this approach?
2. Is there a simpler or better alternative?
3. Are there any files or areas of the codebase that should be considered but aren't mentioned?
4. Any other suggestions or concerns?
Be concise and practical. Focus on actionable feedback. If the plan looks solid, say so briefly — don't invent problems.
```
### Step 2: Run Copilot
```bash
LOGDIR=$(node $HOME/.claude/scripts/get-logdir.js)
mkdir -p "$LOGDIR"
DATETIME=$(date +%Y%m%d_%H%M%S)
bash $HOME/.claude/skills/gco/scripts/gco-run.sh \
"<prompt>" \
"$LOGDIR/${DATETIME}-gco-2nd.md" \
"$LOGDIR/${DATETIME}-gco-2nd-stderr.log"
```
**Timeout: 15 minutes.**
### Step 3: Collect Results
1. Read the output file
2. If empty or missing, check stderr log for errors (a 402 no-quota error means Copilot Premium is exhausted — treat it as a failure)
3. If Copilot timed out, failed, or produced no output, skip — the plan proceeds without the second opinion
### Step 4: Return Feedback
Return the Copilot feedback to the caller. The caller decides whether to incorporate it into the plan.
**No fallback needed.** If Copilot fails, skip — the plan proceeds without the second opinion. This is advisory, not critical.
## When Called by /x-as-pr or /x-wt-teams
1. After forming an initial plan, send it to Copilot for feedback
2. If useful feedback is returned, update the plan
3. Optionally re-run with the updated plan (up to 3 iterations total)
4. Finalize and proceed with implementation
## Important Notes
- Copilot reads workspace files for context — no need to paste file contents into the prompt
- All file writing done by Claude Code, never by Copilot
- This is advisory — never block the workflow if Copilot is unresponsive
- NEVER use `~` in paths — use `$HOME`Related Skills
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watch-ci
Watch GitHub PR CI checks in the background and notify on completion. Use when: (1) User wants to monitor CI/CD status, (2) User says 'watch CI', 'check CI', 'monitor checks', or 'wait for CI', (3) User wants to know when checks pass or fail. Runs a background gh polling shell loop (NOT a subagent — near-zero token cost), sends macOS notification on completion. Also handles merged PRs by watching the target branch CI.
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