Code Review Checklist
shareAI-lab/learn-claude-code
Reviews code against a five-part checklist covering security, correctness, performance, maintainability and testing, and reports findings in a fixed format.
Add a custom function tool to a Strands agent in Python or TypeScript.
Install Add Tool
$ npx skills add strands-agents/harness-sdk --skill add-tool -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install strands-agents/harness-sdk add-tool --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/strands-agents/harness-sdk.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/strands/skills/add-tool .claude/skills/add-tool && 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 "add-tool" agent skill from https://github.com/strands-agents/harness-sdk/tree/main/.agents/skills/strands/skills/add-tool into .claude/skills/add-tool/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-tool", 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/strands-agents/harness-sdk/tree/main/.agents/skills/strands/skills/add-toolType 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 strands-agents/harness-sdk --skill add-tool -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install strands-agents/harness-sdk add-tool --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/strands-agents/harness-sdk.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.agents/skills/strands/skills/add-tool .agents/skills/add-tool && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "add-tool" agent skill from https://github.com/strands-agents/harness-sdk/tree/main/.agents/skills/strands/skills/add-tool into .agents/skills/add-tool/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-tool", 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 strands-agents/harness-sdk --skill add-tool -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install strands-agents/harness-sdk add-tool --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/strands-agents/harness-sdk.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.agents/skills/strands/skills/add-tool .cursor/skills/add-tool && 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 "add-tool" agent skill from https://github.com/strands-agents/harness-sdk/tree/main/.agents/skills/strands/skills/add-tool into .cursor/skills/add-tool/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-tool", 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/strands-agents/harness-sdk.git --path .agents/skills/strands/skills/add-tool--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 strands-agents/harness-sdk --skill add-tool -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install strands-agents/harness-sdk add-tool --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/strands-agents/harness-sdk.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.agents/skills/strands/skills/add-tool .gemini/skills/add-tool && 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 "add-tool" agent skill from https://github.com/strands-agents/harness-sdk/tree/main/.agents/skills/strands/skills/add-tool into .gemini/skills/add-tool/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-tool", 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 strands-agents/harness-sdk add-toolInstalls 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 strands-agents/harness-sdk --skill add-tool -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/strands-agents/harness-sdk.git skills-src && mkdir -p .github/skills && cp -r skills-src/.agents/skills/strands/skills/add-tool .github/skills/add-tool && 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 "add-tool" agent skill from https://github.com/strands-agents/harness-sdk/tree/main/.agents/skills/strands/skills/add-tool into .github/skills/add-tool/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-tool", 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 strands-agents/harness-sdk --skill add-tool -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install strands-agents/harness-sdk add-tool --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/strands-agents/harness-sdk.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.agents/skills/strands/skills/add-tool .opencode/skills/add-tool && 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 "add-tool" agent skill from https://github.com/strands-agents/harness-sdk/tree/main/.agents/skills/strands/skills/add-tool into .opencode/skills/add-tool/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "add-tool", 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-tool- GitHub stars
- 8.7k
- Token cost
- ~171 tokens
- SKILL.md length
- 62 words
- Files
- 1
- Skills in repo
- 14
- Repo updated
- First seen
- Licence
- Apache-2.0
At a glance
Add a custom function tool to a Strands agent in Python or TypeScript.
- The user asks to let a Strands agent call application code
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
- Another deterministic capability
What it does
Add Tool is an agent skill from strands-agents/harness-sdk. Add a custom function tool to a Strands agent in Python or TypeScript. Use when the user asks to let a Strands agent call application code, an API, or another deterministic capability.
Its SKILL.md is about 170 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 Development. It works with Python and TypeScript. The repository describes itself as: Build an agent harness and control it end-to-end. Open-source SDK for production AI agents in Python & TypeScript - any model, any cloud. The licence is Apache-2.0.
When your agent uses it
- The user asks to let a Strands agent call application code
- Another deterministic capability
Example prompts
- “/add-tool”
Requirements
- Python 3
What it can do on your machine
Read from SKILL.md and the folder at commit e519d67. 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
Add Tool loads about 171 tokens when it runs. Until then it costs about 48 tokens; SKILL.md has 62 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 strands-agents/harness-sdk at commit e519d67, republished under its Apache-2.0 licence (© strands-agents). 62 words, ~171 tokens.
Download SKILL.mdSave it as
.claude/skills/add-tool/SKILL.md (or your agent's skills folder).- name
- add-tool
- description
- Add a custom function tool to a Strands agent in Python or TypeScript. Use when the user asks to let a Strands agent call application code, an API, or another deterministic capability.
Add a tool to a Strands agent
Read the shared Strands skill and the tool guide completely.
Inspect the existing agent and implement one narrow tool with a model-readable description and typed input schema. Keep secrets and caller identity out of model-visible parameters. Test the deterministic capability directly, then exercise an agent request that requires the tool when model credentials are available.
© strands-agents, 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
Just SKILL.md in .agents/skills/strands/skills/add-tool of strands-agents/harness-sdk.
Open the folder on GitHubat commit e519d67
Compare with similar skills
Add Tool 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 |
|---|---|---|---|---|---|---|
| Add Tool this skillstrands-agents/harness-sdk | 8.7k | — | ~171 | Automated safety check: Pass | Apache-2.0 | |
| Code Review ChecklistshareAI-lab/learn-claude-code | 78k | 5 repos | ~1.1k | Automated safety check: Pass | MIT | |
| Skyvern Version BumpSkyvern-AI/skyvern | 23k | — | ~1k | Automated safety check: Notes | AGPL-3.0 | |
| Mirage VFS Adapter Authoringstrukto-ai/mirage | 3.7k | — | ~2.5k | Automated safety check: Pass | Apache-2.0 | |
| jscpd Code Migration Trackerkucherenko/jscpd | 6.4k | — | ~5k | Automated safety check: Pass | MIT | |
| Code Reviewerjewbetcha/opentrace | 116 | 2 repos | ~1.1k | Automated safety check: Notes | MIT |
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Measures a code port between languages or frameworks with jscpd's function-level comparison, porting tests before code and tracking what is left unmatched.
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Questions about Add Tool
What does Add Tool do?
Add a custom function tool to a Strands agent in Python or TypeScript. Add Tool is an agent skill from strands-agents/harness-sdk. Add a custom function tool to a Strands agent in Python or TypeScript.
When should I use Add Tool?
Add Tool fits situations like: the user asks to let a Strands agent call application code; another deterministic capability.
How do I install Add Tool in Claude Code?
Run `npx skills add strands-agents/harness-sdk --skill add-tool -a claude-code`. Or copy the skill folder (.agents/skills/strands/skills/add-tool in strands-agents/harness-sdk) into .claude/skills/add-tool in your project. Claude Code loads it when a task matches its description.
How do I install Add Tool in Codex?
Run `npx skills add strands-agents/harness-sdk --skill add-tool -a codex`. Or copy the skill folder (.agents/skills/strands/skills/add-tool in strands-agents/harness-sdk) into .agents/skills/add-tool in your project. Codex loads it when a task matches its description.
Can I use Add Tool 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 strands-agents/harness-sdk --skill add-tool -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-tool, .gemini/skills/add-tool, .github/skills/add-tool and .opencode/skills/add-tool in your project.
What does Add Tool need to run?
SKILL.md names no scripts, command-line tools or credentials: Add Tool is instructions for the agent only. Our summary lists: Python 3.
Does Add Tool 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 Add Tool 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 Tool use?
Add Tool 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 Add Tool use?
About 171 tokens (SKILL.md is roughly 684 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 Tool?
Skills that share tags, products or a category with Add Tool: Code Review Checklist (shareAI-lab/learn-claude-code, 78k stars), Skyvern Version Bump (Skyvern-AI/skyvern, 23k stars), Mirage VFS Adapter Authoring (strukto-ai/mirage, 3.7k stars) and jscpd Code Migration Tracker (kucherenko/jscpd, 6.4k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Add Tool?
strands-agents (a GitHub organization) maintains it in strands-agents/harness-sdk, which has 8,731 GitHub stars. The repository holds 14 skills in this directory. The repository was last updated on October 7, 2026.
Source: strands-agents/harness-sdk on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.