MCP Server Builder
anthropics/skills
Guides the design and implementation of Model Context Protocol servers in TypeScript or Python, from tool naming and error messages to evaluation.
Evaluate arithmetic expressions using a sandboxed Python script.
Apache-2.0Auto-check passed
Install Calculator
$ npx skills add ag2ai/build-with-ag2 --skill calculator -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install ag2ai/build-with-ag2 calculator --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/ag2ai/build-with-ag2.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/calculator .claude/skills/calculator && 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 "calculator" agent skill from https://github.com/ag2ai/build-with-ag2/tree/main/.agents/skills/calculator into .claude/skills/calculator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "calculator", 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/ag2ai/build-with-ag2/tree/main/.agents/skills/calculatorType 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 ag2ai/build-with-ag2 --skill calculator -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install ag2ai/build-with-ag2 calculator --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ag2ai/build-with-ag2.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.agents/skills/calculator .agents/skills/calculator && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "calculator" agent skill from https://github.com/ag2ai/build-with-ag2/tree/main/.agents/skills/calculator into .agents/skills/calculator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "calculator", 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 ag2ai/build-with-ag2 --skill calculator -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install ag2ai/build-with-ag2 calculator --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ag2ai/build-with-ag2.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.agents/skills/calculator .cursor/skills/calculator && 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 "calculator" agent skill from https://github.com/ag2ai/build-with-ag2/tree/main/.agents/skills/calculator into .cursor/skills/calculator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "calculator", 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/ag2ai/build-with-ag2.git --path .agents/skills/calculator--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 ag2ai/build-with-ag2 --skill calculator -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install ag2ai/build-with-ag2 calculator --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ag2ai/build-with-ag2.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.agents/skills/calculator .gemini/skills/calculator && 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 "calculator" agent skill from https://github.com/ag2ai/build-with-ag2/tree/main/.agents/skills/calculator into .gemini/skills/calculator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "calculator", 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 ag2ai/build-with-ag2 calculatorInstalls 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 ag2ai/build-with-ag2 --skill calculator -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/ag2ai/build-with-ag2.git skills-src && mkdir -p .github/skills && cp -r skills-src/.agents/skills/calculator .github/skills/calculator && 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 "calculator" agent skill from https://github.com/ag2ai/build-with-ag2/tree/main/.agents/skills/calculator into .github/skills/calculator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "calculator", 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 ag2ai/build-with-ag2 --skill calculator -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install ag2ai/build-with-ag2 calculator --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ag2ai/build-with-ag2.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.agents/skills/calculator .opencode/skills/calculator && 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 "calculator" agent skill from https://github.com/ag2ai/build-with-ag2/tree/main/.agents/skills/calculator into .opencode/skills/calculator/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "calculator", 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
calculator- GitHub stars
- 252
- Token cost
- ~182 tokens
- SKILL.md length
- 80 words
- Files
- 2 (incl. scripts)
- Skills in repo
- 16
- Repo updated
- First seen
- Licence
- Apache-2.0
At a glance
Evaluate arithmetic expressions using a sandboxed Python script.
- SKILL.md covers How to use and Examples
- Runs Python scripts from its folder
What it does
Calculator is an agent skill from ag2ai/build-with-ag2. Evaluate arithmetic expressions using a sandboxed Python script.
Its SKILL.md is about 180 tokens, which your agent loads only when the skill is triggered. The skill folder holds 2 other files, including scripts (for example `scripts/calc.py`).
It works with Python. The repository describes itself as: Sample code and application showcases to get you going with AG2 (formally AutoGen). The licence is Apache-2.0.
Example prompts
- “/calculator”
Requirements
- Python 3
What it can do on your machine
Read from SKILL.md and the folder at commit 29eeac3. 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
Ships 1 file in scripts/ (Python), which the agent can run.
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
Calculator loads about 182 tokens when it runs. Until then it costs about 19 tokens; SKILL.md has 80 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); the scripts in this folder are not scanned.
SKILL.md
The full file from ag2ai/build-with-ag2 at commit 29eeac3, republished under its Apache-2.0 licence (© ag2ai). 80 words, ~182 tokens.
Download SKILL.mdSave it as
.claude/skills/calculator/SKILL.md (or your agent's skills folder). This skill also uses 1 other file; get the full folder from GitHub.- name
- calculator
- description
- Evaluate arithmetic expressions using a sandboxed Python script.
- version
- 0.1.0
Calculator
Use this skill whenever the user asks for an arithmetic calculation (addition, subtraction, multiplication, division, exponentiation, modulo, or any expression that combines them).
How to use
Call the run_skill_script tool with:
name:"calculator"script:"calc.py"args: a single-element list containing the expression as a string, e.g.["(2 + 3) * 4"].
The script prints the result of the expression. Report the printed value back to the user verbatim.
Examples
- "What's 17 * 23?" →
args=["17 * 23"] - "Compute (100 - 7) / 3" →
args=["(100 - 7) / 3"]
© ag2ai, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
SKILL.md and 1 other file (scripts) in .agents/skills/calculator of ag2ai/build-with-ag2.
- SKILL.md
- scripts/calc.py
Open the folder on GitHubat commit 29eeac3
Compare with similar skills
Calculator 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 |
|---|---|---|---|---|---|---|
| Calculator this skillag2ai/build-with-ag2 | 252 | — | ~182 | Automated safety check: Pass | Apache-2.0 | |
| MCP Server Builderanthropics/skills | 180k | 63 repos | ~2.3k | Automated safety check: Pass | Apache-2.0 | |
| PDF Processinganthropics/skills | 180k | 48 repos | ~2k | Automated safety check: Pass | Proprietary | |
| NotebookLM Research AssistantPleasePrompto/notebooklm-skill | 7.8k | 14 repos | ~2.4k | Automated safety check: Notes | MIT | |
| Manim Video Productionbrowser-use/video-use | 28k | 6 repos | ~3k | Automated safety check: Pass | MIT | |
| Code Review ChecklistshareAI-lab/learn-claude-code | 78k | 5 repos | ~1.1k | Automated safety check: Pass | MIT |
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- Official
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Related
Works with
Questions about Calculator
What does Calculator do?
Evaluate arithmetic expressions using a sandboxed Python script. Calculator is an agent skill from ag2ai/build-with-ag2. Evaluate arithmetic expressions using a sandboxed Python script.
How do I install Calculator in Claude Code?
Run `npx skills add ag2ai/build-with-ag2 --skill calculator -a claude-code`. Or copy the skill folder (.agents/skills/calculator in ag2ai/build-with-ag2) into .claude/skills/calculator in your project. Claude Code loads it when a task matches its description.
How do I install Calculator in Codex?
Run `npx skills add ag2ai/build-with-ag2 --skill calculator -a codex`. Or copy the skill folder (.agents/skills/calculator in ag2ai/build-with-ag2) into .agents/skills/calculator in your project. Codex loads it when a task matches its description.
Can I use Calculator 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 ag2ai/build-with-ag2 --skill calculator -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/calculator, .gemini/skills/calculator, .github/skills/calculator and .opencode/skills/calculator in your project.
What does Calculator need to run?
Going by SKILL.md and its folder, Calculator needs Python for the scripts in its folder. Our summary lists: Python 3.
Does Calculator 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 Calculator 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. The check reads SKILL.md only: the scripts in the folder are not scanned, so read them before running anything.
What licence does Calculator use?
Calculator is published under the Apache-2.0 licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Calculator use?
About 182 tokens (SKILL.md is roughly 728 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 Calculator?
Skills that share tags, products or a category with Calculator: MCP Server Builder (anthropics/skills, 180k stars), PDF Processing (anthropics/skills, 180k stars), NotebookLM Research Assistant (PleasePrompto/notebooklm-skill, 7.8k stars) and Manim Video Production (browser-use/video-use, 28k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Calculator?
ag2ai (a GitHub organization) maintains it in ag2ai/build-with-ag2, which has 252 GitHub stars. The repository holds 16 skills in this directory. The repository was last updated on September 6, 2026.
Source: ag2ai/build-with-ag2 on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.