Agent skill

Add Cheatcode

by runtimeverification in runtimeverification/kontrol

Add a new Foundry cheatcode to Kontrol (K rules, selector, Solidity test, CI registration).

BSD-3-ClauseAuto-check passedBackend & APIs

Install Add Cheatcode

skills CLI

$ npx skills add runtimeverification/kontrol --skill add-cheatcode -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install runtimeverification/kontrol add-cheatcode --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/runtimeverification/kontrol.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.claude/skills/add-cheatcode .claude/skills/add-cheatcode && rm -rf skills-src

Use ~/.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/

Paste into Claude Code

Install the "add-cheatcode" agent skill from https://github.com/runtimeverification/kontrol/tree/master/.claude/skills/add-cheatcode into .claude/skills/add-cheatcode/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-cheatcode", 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

$skill-installer install https://github.com/runtimeverification/kontrol/tree/master/.claude/skills/add-cheatcode

Type 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.

skills CLI

$ npx skills add runtimeverification/kontrol --skill add-cheatcode -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install runtimeverification/kontrol add-cheatcode --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/runtimeverification/kontrol.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.claude/skills/add-cheatcode .agents/skills/add-cheatcode && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "add-cheatcode" agent skill from https://github.com/runtimeverification/kontrol/tree/master/.claude/skills/add-cheatcode into .agents/skills/add-cheatcode/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-cheatcode", 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.

skills CLI

$ npx skills add runtimeverification/kontrol --skill add-cheatcode -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install runtimeverification/kontrol add-cheatcode --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/runtimeverification/kontrol.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.claude/skills/add-cheatcode .cursor/skills/add-cheatcode && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "add-cheatcode" agent skill from https://github.com/runtimeverification/kontrol/tree/master/.claude/skills/add-cheatcode into .cursor/skills/add-cheatcode/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-cheatcode", 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

$ gemini skills install https://github.com/runtimeverification/kontrol.git --path .claude/skills/add-cheatcode

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add runtimeverification/kontrol --skill add-cheatcode -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install runtimeverification/kontrol add-cheatcode --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/runtimeverification/kontrol.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.claude/skills/add-cheatcode .gemini/skills/add-cheatcode && rm -rf skills-src

Use ~/.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/

Paste into Gemini CLI

Install the "add-cheatcode" agent skill from https://github.com/runtimeverification/kontrol/tree/master/.claude/skills/add-cheatcode into .gemini/skills/add-cheatcode/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-cheatcode", 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.

GitHub CLI

$ gh skill install runtimeverification/kontrol add-cheatcode

Installs 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).

skills CLI

$ npx skills add runtimeverification/kontrol --skill add-cheatcode -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/runtimeverification/kontrol.git skills-src && mkdir -p .github/skills && cp -r skills-src/.claude/skills/add-cheatcode .github/skills/add-cheatcode && rm -rf skills-src

Use ~/.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/

Paste into GitHub Copilot

Install the "add-cheatcode" agent skill from https://github.com/runtimeverification/kontrol/tree/master/.claude/skills/add-cheatcode into .github/skills/add-cheatcode/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-cheatcode", 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.

skills CLI

$ npx skills add runtimeverification/kontrol --skill add-cheatcode -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install runtimeverification/kontrol add-cheatcode --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/runtimeverification/kontrol.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.claude/skills/add-cheatcode .opencode/skills/add-cheatcode && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "add-cheatcode" agent skill from https://github.com/runtimeverification/kontrol/tree/master/.claude/skills/add-cheatcode into .opencode/skills/add-cheatcode/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-cheatcode", 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: add-cheatcode
GitHub stars: 125
Token cost: ~903 tokens
SKILL.md length: 366 words
Files: 1
Skills in repo: 3
Repo updated: Oct 5, 2026
First seen: Oct 7, 2026
Licence: BSD-3-Clause

At a glance

Add a new Foundry cheatcode to Kontrol (K rules, selector, Solidity test, CI registration).

Works in 8 steps: Add the cheatcode section in… → Add the selector rule in the implemented… → Extend the subconfiguration (at the top… → …
Implementing a new vm
Calls make
Tasks that involve Smart contracts

What it does

Add Cheatcode is an agent skill from runtimeverification/kontrol. Add a new Foundry cheatcode to Kontrol (K rules, selector, Solidity test, CI registration). Use when implementing a new vm. or Kontrol-proprietary cheatcode.

Its SKILL.md is about 900 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It sits in Backend & APIs, covering Smart contracts. It works with Solidity. The licence is BSD-3-Clause.

When your agent uses it

Implementing a new vm
Tasks that involve Smart contracts

Example prompts

“/add-cheatcode”

Workflow steps

8 steps, taken from the first numbered list in SKILL.md.

Add the cheatcode section in src/kontrol/kdist/cheatcodes.md, in the appropriate location among the other cheatcode rules.
Add the selector rule in the implemented selectors list
Extend the subconfiguration (at the top of cheatcodes.md) if the implementation requires storing new state across calls.
Add Solidity tests in src/tests/integration/test-data/test/.
Register tests in src/tests/integration/test-data/
Rebuild using the /build skill, then run the new tests under the end-to-end suite
If this is a Kontrol-proprietary cheatcode (not a standard Foundry vm.* cheatcode): notify the user that the cheatcode interface must also…
Update CLAUDE.md: add a row for the new cheatcode in the appropriate table (Foundry cheatcodes or Kontrol-proprietary cheatcodes) under…

What it can do on your machine

Read from SKILL.md and the folder at commit 1649663. 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
Shell commands in SKILL.md call:
- make
From the folder's file list and the shell code blocks in SKILL.md.
Network
Links to these hosts (documentation or services it may open):
- github.com
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

Add Cheatcode loads about 903 tokens when it runs. Until then it costs about 43 tokens; SKILL.md has 366 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~43
When it runs · the whole SKILL.md, loaded when a task matches: ~903

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 runtimeverification/kontrol at commit 1649663, republished under its BSD-3-Clause licence (© runtimeverification). 366 words, ~903 tokens.

Download SKILL.mdSave it as .claude/skills/add-cheatcode/SKILL.md (or your agent's skills folder).

name: add-cheatcode
description: Add a new Foundry cheatcode to Kontrol (K rules, selector, Solidity test, CI registration). Use when implementing a new vm.* or Kontrol-proprietary cheatcode.
argument-hint: <cheatcode_signature>

Add a new Foundry cheatcode to Kontrol. The cheatcode to implement is: $ARGUMENTS

Follow these steps:

Add the cheatcode section in src/kontrol/kdist/cheatcodes.md, in the appropriate location among the other cheatcode rules. Follow the documentation style of adjacent sections (header, Solidity signature block, prose explanation, K rule).

K rule template:
k
```
    rule [cheatcode.call.<name>]:
         <k> #cheatcode_call SELECTOR ARGS => .K ... </k>
         <output> _ => #bufStrict(32, /* result */) </output>
      requires SELECTOR ==Int selector ( "<cheatcode_signature>" )
      [preserves-definedness]
```
ABI-encoded ARGS: each parameter occupies 32 bytes. As example, #asWord(#range(ARGS, N*32, 32)) for the Nth argument (0-indexed). If the cheatcode writes state instead of returning a value, omit <output> and write to the appropriate configuration cell.
Add the selector rule in the implemented selectors list:
k
```
rule ( selector ( "<cheatcode_signature>" ) => <computed_selector_int> )
```
Compute the decimal selector with ./scripts/selector "<cheatcode_signature>". If the cheatcode was previously in the non-implemented list, move it instead of duplicating it.
Extend the subconfiguration (at the top of cheatcodes.md) if the implementation requires storing new state across calls. Document any new cell with a comment explaining its purpose.
Add Solidity tests in src/tests/integration/test-data/test/. Check first whether a test already exists. Naming: <CheatcodeName>.t.sol, contract <CheatcodeName>Test.

Choose the test strategy based on what the cheatcode affects:
- Assertion-testable (effect visible at Solidity level): use assert* calls directly. Example: computeCreateAddress can predict a value and assert it matches.
- KCFG-testable (effect is on proof structure, not a runtime value): use a golden expected-output file in test-data/show/. Examples: forgetBranch (removes a branch), symbolic variable renaming (changes KCFG node labels), console.log (emits output not visible to assertions). Add the test to end-to-end-prove-show so the snapshot is captured and compared on each run.
Register tests in src/tests/integration/test-data/:
- Add passing signatures to end-to-end-prove-all
- Add expected-failure signatures to foundry-fail (if any)
- Remove from end-to-end-prove-skip if present
Rebuild using the /build skill, then run the new tests under the end-to-end suite:
bash
```
make test-integration TEST_ARGS="-k 'test_kontrol_end_to_end and <TestClass>'"
```
If this is a Kontrol-proprietary cheatcode (not a standard Foundry vm.* cheatcode): notify the user that the cheatcode interface must also be added to the runtimeverification/kontrol-cheatcodes repository, and that this must be done as a separate PR there.
Update CLAUDE.md: add a row for the new cheatcode in the appropriate table (Foundry cheatcodes or Kontrol-proprietary cheatcodes) under the ## Cheatcodes: Foundry vs Kontrol-proprietary section. Follow the format of existing rows: | \signature` | purpose |`.

Show full SKILL.md (12 more words)Show less

After all steps, summarise what was added and which files were changed.

Files

Just SKILL.md in .claude/skills/add-cheatcode of runtimeverification/kontrol.

Open the folder on GitHubat commit 1649663

Compare with similar skills

Add Cheatcode 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.

Add Cheatcode compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Add Cheatcode this skillruntimeverification/kontrol	125	—	~903	Automated safety check: Pass	BSD-3-Clause	2 days ago
Fizz Convertpashov/skills	1.2k	2 repos	~3.7k	Automated safety check: Pass	MIT	2 days ago
Feynman Auditor0xiehnnkta/nemesis-auditor	244	1 repos	~11k	Automated safety check: Pass	MIT	6 mo ago
Smart Contract Auditgreatpie/smart-contract-audit-skill	101	—	~1.1k	Automated safety check: Pass	None	7 mo ago
RadarAuditware/radar	154	—	~2.1k	Automated safety check: Pass	GPL-3.0	1 mo ago
Solidity AuditorGabson0x/bountyforge	443	—	~3.7k	Automated safety check: Pass	None	20 days ago

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Works with

Solidity

Questions about Add Cheatcode

What does Add Cheatcode do?

Add a new Foundry cheatcode to Kontrol (K rules, selector, Solidity test, CI registration). Add Cheatcode is an agent skill from runtimeverification/kontrol. Add a new Foundry cheatcode to Kontrol (K rules, selector, Solidity test, CI registration).

When should I use Add Cheatcode?

Add Cheatcode fits situations like: implementing a new vm; tasks that involve Smart contracts.

How do I install Add Cheatcode in Claude Code?

Run `npx skills add runtimeverification/kontrol --skill add-cheatcode -a claude-code`. Or copy the skill folder (.claude/skills/add-cheatcode in runtimeverification/kontrol) into .claude/skills/add-cheatcode in your project. Claude Code loads it when a task matches its description.

How do I install Add Cheatcode in Codex?

Run `npx skills add runtimeverification/kontrol --skill add-cheatcode -a codex`. Or copy the skill folder (.claude/skills/add-cheatcode in runtimeverification/kontrol) into .agents/skills/add-cheatcode in your project. Codex loads it when a task matches its description.

Can I use Add Cheatcode 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 runtimeverification/kontrol --skill add-cheatcode -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/add-cheatcode, .gemini/skills/add-cheatcode, .github/skills/add-cheatcode and .opencode/skills/add-cheatcode in your project.

What does Add Cheatcode need to run?

Going by SKILL.md and its folder, Add Cheatcode needs the command-line tools its instructions call (make).

Does Add Cheatcode access the network?

SKILL.md names 1 domain. As links in the text: github.com. This is read from the text; nothing was executed.

Is Add Cheatcode 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 Add Cheatcode use?

Add Cheatcode is published under the BSD-3-Clause licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Add Cheatcode use?

About 903 tokens (SKILL.md is roughly 3.6k 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 Add Cheatcode?

Skills that share tags, products or a category with Add Cheatcode: Fizz Convert (pashov/skills, 1.2k stars), Feynman Auditor (0xiehnnkta/nemesis-auditor, 244 stars), Smart Contract Audit (greatpie/smart-contract-audit-skill, 101 stars) and Radar (Auditware/radar, 154 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Add Cheatcode?

runtimeverification (a GitHub organization) maintains it in runtimeverification/kontrol, which has 125 GitHub stars. The repository holds 3 skills in this directory. The repository was last updated on October 5, 2026.

Source: runtimeverification/kontrol on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Install Add Cheatcode

Facts

At a glance

What it does

When your agent uses it

Example prompts

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Files

Compare with similar skills

Similar skills

More from runtimeverification/kontrol

Related

Questions about Add Cheatcode