Case Review
sickn33/agentic-awesome-skills
Quality-gate review of a reverse-engineering or assessment case package: scope readiness, Evidence-to-Finding-to-Path traceability, work-item coverage, timeline consistency, and artifact hashes.
The strongest possible case AGAINST what you just wrote — argued to win, not to check a box.
MITAuto-check passed
Install Devils Twin
$ npx skills add mohitagw15856/pm-claude-skills --skill devils-twin -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install mohitagw15856/pm-claude-skills devils-twin --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/mohitagw15856/pm-claude-skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/devils-twin .claude/skills/devils-twin && 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 "devils-twin" agent skill from https://github.com/mohitagw15856/pm-claude-skills/tree/main/skills/devils-twin into .claude/skills/devils-twin/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "devils-twin", 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/mohitagw15856/pm-claude-skills/tree/main/skills/devils-twinType 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 mohitagw15856/pm-claude-skills --skill devils-twin -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install mohitagw15856/pm-claude-skills devils-twin --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mohitagw15856/pm-claude-skills.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/devils-twin .agents/skills/devils-twin && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "devils-twin" agent skill from https://github.com/mohitagw15856/pm-claude-skills/tree/main/skills/devils-twin into .agents/skills/devils-twin/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "devils-twin", 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 mohitagw15856/pm-claude-skills --skill devils-twin -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install mohitagw15856/pm-claude-skills devils-twin --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mohitagw15856/pm-claude-skills.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/devils-twin .cursor/skills/devils-twin && 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 "devils-twin" agent skill from https://github.com/mohitagw15856/pm-claude-skills/tree/main/skills/devils-twin into .cursor/skills/devils-twin/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "devils-twin", 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/mohitagw15856/pm-claude-skills.git --path skills/devils-twin--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 mohitagw15856/pm-claude-skills --skill devils-twin -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install mohitagw15856/pm-claude-skills devils-twin --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mohitagw15856/pm-claude-skills.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/devils-twin .gemini/skills/devils-twin && 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 "devils-twin" agent skill from https://github.com/mohitagw15856/pm-claude-skills/tree/main/skills/devils-twin into .gemini/skills/devils-twin/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "devils-twin", 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 mohitagw15856/pm-claude-skills devils-twinInstalls 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 mohitagw15856/pm-claude-skills --skill devils-twin -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/mohitagw15856/pm-claude-skills.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/devils-twin .github/skills/devils-twin && 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 "devils-twin" agent skill from https://github.com/mohitagw15856/pm-claude-skills/tree/main/skills/devils-twin into .github/skills/devils-twin/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "devils-twin", 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 mohitagw15856/pm-claude-skills --skill devils-twin -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install mohitagw15856/pm-claude-skills devils-twin --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mohitagw15856/pm-claude-skills.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/devils-twin .opencode/skills/devils-twin && 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 "devils-twin" agent skill from https://github.com/mohitagw15856/pm-claude-skills/tree/main/skills/devils-twin into .opencode/skills/devils-twin/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "devils-twin", 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
devils-twin- GitHub stars
- 1.4k
- Token cost
- ~965 tokens
- SKILL.md length
- 522 words
- Files
- 1
- Skills in repo
- 1,348
- Repo updated
- First seen
- Licence
- MIT
At a glance
The strongest possible case AGAINST what you just wrote — argued to win, not to check a box.
- Works in 4 steps: The opposing memo (400-600 words) —… → The battle map — your document's key… → The pre-emption — the single paragraph… → …
- A document is about to ship and everyone around it already agrees: the twin writes the oppositions best memo (not a critique of yours)
- SKILL.md covers Required Inputs, How the Twin Argues, Output Format and Quality Checks, plus 2 more sections
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Devils Twin is an agent skill from mohitagw15856/pm-claude-skills. The strongest possible case AGAINST what you just wrote — argued to win, not to check a box. Use when a document is about to ship and everyone around it already agrees: the twin writes the opposition's best memo (not a critique of yours), so you meet the real counter-argument before your audience does. Produces the opposing memo, the map of which of your claims it defeats/dents/leaves standing, and the pre-emption paragraph worth adding.
Its SKILL.md is about 970 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
The repository describes itself as: 1255 professional Agent Skills for Claude, ChatGPT, Gemini, Cursor & Codex — PRDs, postmortems, leases, medical bills, layoffs, go-bags, new countries. Plain markdown, MIT, in… The licence is MIT.
When your agent uses it
- A document is about to ship and everyone around it already agrees: the twin writes the oppositions best memo (not a critique of yours)
- So you meet the real counter-argument before your audience does
Example prompts
- “/devils-twin”
Workflow steps
4 steps, taken from the first numbered list in SKILL.md.
- The opposing memo (400-600 words) — standalone, signed by the persona ("Memo from the office of the CFO"), good enough that a reader…
- The battle map — your document's key claims, each marked: 💀 defeated (the twin's counter is simply better) / 🩸 dented (survives with…
- The pre-emption — the single paragraph to ADD to your document that answers the twin's best point before anyone makes it, drafted in your…
- The honest verdict — one line: ship as is, repair first, or the twin's case is actually right (say so; it happens, and it's the cheapest…
What it can do on your machine
Read from SKILL.md and the folder at commit 1cbf1f0. 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
Devils Twin loads about 965 tokens when it runs. Until then it costs about 113 tokens; SKILL.md has 522 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
The full file from mohitagw15856/pm-claude-skills at commit 1cbf1f0, republished under its MIT licence (© mohitagw15856). 522 words, ~965 tokens.
Download SKILL.mdSave it as
.claude/skills/devils-twin/SKILL.md (or your agent's skills folder).- name
- devils-twin
- description
- The strongest possible case AGAINST what you just wrote — argued to win, not to check a box. Use when a document is about to ship and everyone around it already agrees: the twin writes the opposition's best memo (not a critique of yours), so you meet the real counter-argument before your audience does. Produces the opposing memo, the map of which of your claims it defeats/dents/leaves standing, and the pre-emption paragraph worth adding.
Devil's Twin
Critique finds weaknesses in your argument. The twin does something scarier: it writes the other side's argument, from their premises, at full strength — the memo your smartest opponent would circulate an hour after yours. If your document survives its twin, it will survive the meeting.
Required Inputs
- The document — full text. The twin argues against the strongest version of what you wrote, so it must see all of it.
- Who would oppose this in real life (optional but sharpening) — the CFO, the incumbent team, the sceptical customer, the regulator. The twin adopts their premises, not a generic contrarian's.
How the Twin Argues
- It starts from the opponent's values (their scoreboard, their risks), not from negations of yours — real opposition is a different worldview, not your worldview with "not" inserted.
- It concedes your strongest point early — sophisticated opponents do; conceding makes the rest of their case credible.
- It uses your own evidence where possible — the most damaging counter-memos re-read your data and reach the other conclusion.
- It is written to persuade your shared audience, in the register of your organisation — a memo, not a rant.
Output Format
- The opposing memo (400-600 words) — standalone, signed by the persona ("Memo from the office of the CFO"), good enough that a reader wouldn't know which document you commissioned.
- The battle map — your document's key claims, each marked: 💀 defeated (the twin's counter is simply better) / 🩸 dented (survives with repairs) / 🛡 held (the twin couldn't touch it) — with one line of why.
- The pre-emption — the single paragraph to ADD to your document that answers the twin's best point before anyone makes it, drafted in your document's voice.
- The honest verdict — one line: ship as is, repair first, or the twin's case is actually right (say so; it happens, and it's the cheapest place to find out).
Show full SKILL.md (217 more words)Show less
Quality Checks
- The memo argues FROM the opponent's premises — deleting "not" from your claims would not reconstruct it
- It concedes at least one of your points — full-spectrum opposition is a strawman wearing a suit
- At least one of your claims is marked 💀 or the twin explains why your case is unusually airtight (rare; suspicious)
- The pre-emption paragraph is drop-in ready — your voice, your document's structure, no "as some may argue" throat-clearing
- If the twin's case is stronger overall, the verdict says so plainly
Anti-Patterns
- Do not write a critique with quotations — the deliverable is the opposition's own memo, structure and all
- Do not make the twin stupid to make you feel good — a weak twin is worse than none; it inoculates you against the wrong argument
- Do not have the twin invent facts — it may reinterpret your evidence and add commonly-known context, never fabricate data
- Do not skip the verdict to stay diplomatic — "repair first" beats a polite shrug
- Do not use the twin on documents whose audience is hostile already — it's for consensus rooms, where nobody else will say this
Example Trigger Phrases
- "Argue against this as hard as you can."
- "Write the opposition's best memo."
- "Everyone agrees with this doc: what's the strongest case against it?"
- "Make the case that we should not do this."
© mohitagw15856, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
Just SKILL.md in skills/devils-twin of mohitagw15856/pm-claude-skills.
Open the folder on GitHubat commit 1cbf1f0
Compare with similar skills
Devils Twin 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 |
|---|---|---|---|---|---|---|
| Devils Twin this skillmohitagw15856/pm-claude-skills | 1.4k | — | ~965 | Automated safety check: Pass | MIT | |
| Case Reviewsickn33/agentic-awesome-skills | 47k | 1 repos | ~1.6k | Automated safety check: Pass | MIT | |
| Case Reviewzhaoxuya520/reverse-skill | 40k | 1 repos | ~1.6k | Automated safety check: Warn | MIT | |
| Clinical Case Reportnexu-io/open-design | 100k | — | ~2.2k | Automated safety check: Pass | Apache-2.0 | |
| Secops Casesgoogle/skills | 21k | — | ~3.2k | Automated safety check: Warn | Apache-2.0 | |
| Case Briefanthropics/claude-for-legal | 9.6k | 3 repos | ~1.6k | Automated safety check: Pass | Apache-2.0 |
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Questions about Devils Twin
What does Devils Twin do?
The strongest possible case AGAINST what you just wrote — argued to win, not to check a box. Devils Twin is an agent skill from mohitagw15856/pm-claude-skills. The strongest possible case AGAINST what you just wrote — argued to win, not to check a box.
When should I use Devils Twin?
Devils Twin fits situations like: A document is about to ship and everyone around it already agrees: the twin writes the oppositions best memo (not a critique of yours); so you meet the real counter-argument before your audience does.
How do I install Devils Twin in Claude Code?
Run `npx skills add mohitagw15856/pm-claude-skills --skill devils-twin -a claude-code`. Or copy the skill folder (skills/devils-twin in mohitagw15856/pm-claude-skills) into .claude/skills/devils-twin in your project. Claude Code loads it when a task matches its description.
How do I install Devils Twin in Codex?
Run `npx skills add mohitagw15856/pm-claude-skills --skill devils-twin -a codex`. Or copy the skill folder (skills/devils-twin in mohitagw15856/pm-claude-skills) into .agents/skills/devils-twin in your project. Codex loads it when a task matches its description.
Can I use Devils Twin 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 mohitagw15856/pm-claude-skills --skill devils-twin -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/devils-twin, .gemini/skills/devils-twin, .github/skills/devils-twin and .opencode/skills/devils-twin in your project.
What does Devils Twin need to run?
SKILL.md names no scripts, command-line tools or credentials: Devils Twin is instructions for the agent only.
Does Devils Twin 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 Devils Twin 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 Devils Twin use?
Devils Twin is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Devils Twin use?
About 965 tokens (SKILL.md is roughly 3.9k 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 Devils Twin?
Skills that share tags, products or a category with Devils Twin: Case Review (sickn33/agentic-awesome-skills, 47k stars), Case Review (zhaoxuya520/reverse-skill, 40k stars), Clinical Case Report (nexu-io/open-design, 100k stars) and Secops Cases (google/skills, 21k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Devils Twin?
mohitagw15856 (a GitHub user) maintains it in mohitagw15856/pm-claude-skills, which has 1,433 GitHub stars. The repository holds 1,348 skills in this directory. The repository was last updated on October 8, 2026.
Source: mohitagw15856/pm-claude-skills on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.