Second Opinion
peterkrueck/Claude-Code-Development-Kit
Get a second opinion from OpenAI's Codex CLI running locally.
Get a rigorous read-only second opinion on finished work through the host's available reviewer capabilities, preferably from a different model provider.
Custom licenceAuto-check passed
Install Double Check
$ npx skills add citypaul/.dotfiles --skill double-check -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install citypaul/.dotfiles double-check --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .claude/skills && cp -r skills-src/claude/.claude/skills/double-check .claude/skills/double-check && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "double-check" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/double-check into .claude/skills/double-check/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "double-check", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/double-checkType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add citypaul/.dotfiles --skill double-check -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install citypaul/.dotfiles double-check --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .agents/skills && cp -r skills-src/claude/.claude/skills/double-check .agents/skills/double-check && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "double-check" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/double-check into .agents/skills/double-check/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "double-check", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add citypaul/.dotfiles --skill double-check -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install citypaul/.dotfiles double-check --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/claude/.claude/skills/double-check .cursor/skills/double-check && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "double-check" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/double-check into .cursor/skills/double-check/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "double-check", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/citypaul/.dotfiles.git --path claude/.claude/skills/double-check--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add citypaul/.dotfiles --skill double-check -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install citypaul/.dotfiles double-check --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/claude/.claude/skills/double-check .gemini/skills/double-check && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "double-check" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/double-check into .gemini/skills/double-check/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "double-check", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install citypaul/.dotfiles double-checkInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add citypaul/.dotfiles --skill double-check -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .github/skills && cp -r skills-src/claude/.claude/skills/double-check .github/skills/double-check && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "double-check" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/double-check into .github/skills/double-check/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "double-check", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add citypaul/.dotfiles --skill double-check -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install citypaul/.dotfiles double-check --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/claude/.claude/skills/double-check .opencode/skills/double-check && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "double-check" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/double-check into .opencode/skills/double-check/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "double-check", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
double-check- GitHub stars
- 740
- Token cost
- ~3.6k tokens
- SKILL.md length
- 1,906 words
- Files
- 3
- Skills in repo
- 44
- Repo updated
- First seen
- Licence
- Custom licence
At a glance
Get a rigorous read-only second opinion on finished work through the host's available reviewer capabilities, preferably from a different model provider.
- Works in 7 steps: Discover Reviewer Capabilities → Configure for Rigor and Safety → Write a Complete Brief → …
- Asked to double-check
- SKILL.md covers When to Use This Skill, Review Modes, Workflow and Reporting, plus 1 more section
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Double Check is an agent skill from citypaul/.dotfiles. Get a rigorous read-only second opinion on finished work through the host's available reviewer capabilities, preferably from a different model provider. Falls back to a fresh same-provider agent only when necessary and labels the reduced independence. Every review includes a mandatory scope-fidelity check against the original requirements — unrequested additions, unrequested removals, and deleted or weakened tests. Use when asked to double-check, verify, cross-check, or get a second opinion, and before shipping…
Its SKILL.md is about 3.6k tokens, which your agent loads only when the skill is triggered. The skill folder holds 3 other files (for example `resources/brief-template.md` and `resources/providers.md`).
When your agent uses it
- Asked to double-check
- Get a second opinion
- Before shipping high-stakes
Example prompts
- “/double-check”
Workflow steps
7 steps, taken from the step headings in SKILL.md.
- Discover Reviewer Capabilities
- Configure for Rigor and Safety
- Write a Complete Brief
- Always Check Scope Fidelity
- Require Actionable Findings
- Resolve Every Finding
- Review the Final State
What it can do on your machine
Read from SKILL.md and the folder at commit cd4028d. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Double Check loads about 3.6k tokens when it runs. Until then it costs about 140 tokens; SKILL.md has 1,906 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
Its licence (Custom licence) doesn't allow us to republish the file, so here is its outline and opening line. It has 1,906 words (~3,555 tokens).
“Review finished work from a context that did not author it. Prefer a genuinely independent reviewer from a different model provider. If none is usable, permit a fresh same-provider agent with no inherited conversation and report that weaker mode explicitly.”
- name
- double-check
Files
SKILL.md and 2 other files in claude/.claude/skills/double-check of citypaul/.dotfiles.
- SKILL.md
- resources/brief-template.md
- resources/providers.md
Open the folder on GitHubat commit cd4028d
Compare with similar skills
Double Check next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Double Check this skillcitypaul/.dotfiles | 740 | — | ~3.6k | Automated safety check: Pass | Custom licence | |
| Second Opinionpeterkrueck/Claude-Code-Development-Kit | 1.4k | — | ~2.4k | Automated safety check: Warn | MIT | |
| The Second Opinionmohitagw15856/pm-claude-skills | 1.4k | — | ~916 | Automated safety check: Pass | MIT | |
| Second Opinion Code Reviewtrailofbits/skills | 7.5k | — | ~1.3k | Automated safety check: Notes | CC-BY-SA-4.0 | |
| Second Opinion Requestmohitagw15856/pm-claude-skills | 1.4k | — | ~1.6k | Automated safety check: Pass | MIT | |
| Second Opinion Geminipeterkrueck/Claude-Code-Development-Kit | 1.4k | — | ~2.3k | Automated safety check: Warn | MIT |
Similar skills
The Second Opinion
mohitagw15856/pm-claude-skills
Deliberately take the opposite position from your leaning and make you defend yours — a forced second opinion that isn't just an echo.
- Official
Second Opinion Code Review
trailofbits/skills
Runs an independent review of uncommitted changes, a branch diff or one commit through the Codex or Antigravity CLI, or both, and reports their findings.
Second Opinion Request
mohitagw15856/pm-claude-skills
Get a second medical opinion without torching the first relationship — when it's warranted, how to raise it with the current doctor, the records package the consulting doctor needs, and how to weigh…
Second Opinion Gemini
peterkrueck/Claude-Code-Development-Kit
Get a second opinion from Google's Gemini Pro via the locally installed Gemini CLI (defaults to gemini-3.1-pro-preview; override with the CLAUDESECONDOPINIONMODEL env var).
Claudex Second Opinion
ccplugins/awesome-claude-code-plugins
Suggests a cross-model second opinion after substantial or risky code changes.
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Questions about Double Check
What does Double Check do?
Get a rigorous read-only second opinion on finished work through the host's available reviewer capabilities, preferably from a different model provider. dotfiles. Get a rigorous read-only second opinion on finished work through the host's available reviewer capabilities, preferably from a different model provider.
When should I use Double Check?
Double Check fits situations like: asked to double-check; get a second opinion; before shipping high-stakes.
How do I install Double Check in Claude Code?
Run `npx skills add citypaul/.dotfiles --skill double-check -a claude-code`. Or copy the skill folder (claude/.claude/skills/double-check in citypaul/.dotfiles) into .claude/skills/double-check in your project. Claude Code loads it when a task matches its description.
How do I install Double Check in Codex?
Run `npx skills add citypaul/.dotfiles --skill double-check -a codex`. Or copy the skill folder (claude/.claude/skills/double-check in citypaul/.dotfiles) into .agents/skills/double-check in your project. Codex loads it when a task matches its description.
Can I use Double Check in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add citypaul/.dotfiles --skill double-check -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/double-check, .gemini/skills/double-check, .github/skills/double-check and .opencode/skills/double-check in your project.
What does Double Check need to run?
SKILL.md names no scripts, command-line tools or credentials: Double Check is instructions for the agent only.
Does Double Check access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Double Check safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Double Check use?
Double Check has a licence file (the repository's licence) that doesn't match a standard licence. Read it on GitHub before reusing the skill.
How many tokens does Double Check use?
About 3.6k tokens (SKILL.md is roughly 14k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Double Check?
Skills that share tags, products or a category with Double Check: Second Opinion (peterkrueck/Claude-Code-Development-Kit, 1.4k stars), The Second Opinion (mohitagw15856/pm-claude-skills, 1.4k stars), Second Opinion Code Review (trailofbits/skills, 7.5k stars) and Second Opinion Request (mohitagw15856/pm-claude-skills, 1.4k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Double Check?
citypaul (a GitHub user) maintains it in citypaul/.dotfiles, which has 740 GitHub stars. The repository holds 44 skills in this directory. The repository was last updated on October 9, 2026.
Source: citypaul/.dotfiles on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.