Agent skill

Strict API

by alirezarezvani in alirezarezvani/claude-skills

A skill your agent uses when the user says 'no hallucinations', 'verify APIs', 'reality check', or 'don't invent functions'.

MITAuto-check passedDevelopment

Install Strict API

skills CLI

$ npx skills add alirezarezvani/claude-skills --skill strict-api -a claude-code

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

GitHub CLI

$ gh skill install alirezarezvani/claude-skills strict-api --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/alirezarezvani/claude-skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/engineering/strict-api .claude/skills/strict-api && 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 "strict-api" agent skill from https://github.com/alirezarezvani/claude-skills/tree/main/engineering/strict-api into .claude/skills/strict-api/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "strict-api", 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/alirezarezvani/claude-skills/tree/main/engineering/strict-api

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 alirezarezvani/claude-skills --skill strict-api -a codex

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

GitHub CLI

$ gh skill install alirezarezvani/claude-skills strict-api --agent codex

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

Manual copy

$ git clone --depth 1 https://github.com/alirezarezvani/claude-skills.git skills-src && mkdir -p .agents/skills && cp -r skills-src/engineering/strict-api .agents/skills/strict-api && 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 "strict-api" agent skill from https://github.com/alirezarezvani/claude-skills/tree/main/engineering/strict-api into .agents/skills/strict-api/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "strict-api", 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 alirezarezvani/claude-skills --skill strict-api -a cursor

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

GitHub CLI

$ gh skill install alirezarezvani/claude-skills strict-api --agent cursor

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

Manual copy

$ git clone --depth 1 https://github.com/alirezarezvani/claude-skills.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/engineering/strict-api .cursor/skills/strict-api && 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 "strict-api" agent skill from https://github.com/alirezarezvani/claude-skills/tree/main/engineering/strict-api into .cursor/skills/strict-api/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "strict-api", 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/alirezarezvani/claude-skills.git --path engineering/strict-api

--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 alirezarezvani/claude-skills --skill strict-api -a gemini-cli

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

GitHub CLI

$ gh skill install alirezarezvani/claude-skills strict-api --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/alirezarezvani/claude-skills.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/engineering/strict-api .gemini/skills/strict-api && 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 "strict-api" agent skill from https://github.com/alirezarezvani/claude-skills/tree/main/engineering/strict-api into .gemini/skills/strict-api/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "strict-api", 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 alirezarezvani/claude-skills strict-api

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 alirezarezvani/claude-skills --skill strict-api -a github-copilot

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

Manual copy

$ git clone --depth 1 https://github.com/alirezarezvani/claude-skills.git skills-src && mkdir -p .github/skills && cp -r skills-src/engineering/strict-api .github/skills/strict-api && 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 "strict-api" agent skill from https://github.com/alirezarezvani/claude-skills/tree/main/engineering/strict-api into .github/skills/strict-api/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "strict-api", 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 alirezarezvani/claude-skills --skill strict-api -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 alirezarezvani/claude-skills strict-api --agent opencode

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

Manual copy

$ git clone --depth 1 https://github.com/alirezarezvani/claude-skills.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/engineering/strict-api .opencode/skills/strict-api && 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 "strict-api" agent skill from https://github.com/alirezarezvani/claude-skills/tree/main/engineering/strict-api into .opencode/skills/strict-api/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "strict-api", 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: strict-api
GitHub stars: 28k
Token cost: ~836 tokens
SKILL.md length: 440 words
Files: 1
Skills in repo: 342
Repo updated: Aug 30, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

A skill your agent uses when the user says 'no hallucinations', 'verify APIs', 'reality check', or 'don't invent functions'.

Works in 4 steps: Identify every API surface in the code… → Verify each one against the user's… → Flag anything uncertain with an inline… → …
The user says no hallucinations
SKILL.md covers Overview, The Only Rule, What This Blocks and Workflow, plus 2 more sections
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Strict API is an agent skill from alirezarezvani/claude-skills. Use when the user says 'no hallucinations', 'verify APIs', 'reality check', or 'don't invent functions'. Prevents the agent from calling methods, imports, or variables that do not provably exist in the user's installed version.

Its SKILL.md is about 840 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 Node.js. The repository describes itself as: 380 Claude Code skills & agent skills & plugins (30+ Agents, 70+ custom commands, 380+ skills, customizable references, scripts)for Claude Code, Codex, Gemini CLI, Cursor, and 8… The licence is MIT.

When your agent uses it

The user says no hallucinations
Dont invent functions

Example prompts

“no hallucinations”
“verify APIs”
“reality check”
“/strict-api”

Requirements

Node.js

Workflow steps

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

Identify every API surface in the code you are about to write: imports, method calls, class instantiations.
Verify each one against the user's stated version. If no version is stated, ask once.
Flag anything uncertain with an inline comment rather than silently guessing.
Prefer verbose-but-correct over terse-but-wrong.

What it can do on your machine

Read from SKILL.md and the folder at commit 19392f7. 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

Strict API loads about 836 tokens when it runs. Until then it costs about 60 tokens; SKILL.md has 440 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~60
When it runs · the whole SKILL.md, loaded when a task matches: ~836

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 alirezarezvani/claude-skills at commit 19392f7, republished under its MIT licence (© alirezarezvani). 440 words, ~836 tokens.

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

name: strict-api
description: Use when the user says 'no hallucinations', 'verify APIs', 'reality check', or 'don't invent functions'. Prevents the agent from calling methods, imports, or variables that do not provably exist in the user's installed version.

Strict API Verification

Inventing a function that doesn't exist is the opposite of efficiency. You wrote a line that looks minimal. You shipped a bug that takes an hour to debug. The true minimal path is: use only what is provably there.

Overview

This skill is a reality-check layer applied before any code is written. It is not about being slow — it is about being correct the first time. Use it alongside minimalist when the user wants both less code and verified code.

The Only Rule

Before you write any function call, import, or method access, you must be able to answer:

"Does this exist in the version the user is running?"

If the answer is "probably" or "I think so" — stop. You don't know. Say so.

What This Blocks

Made-up methods:

fs.readFileLines() does not exist in Node.js.
path.combine() is .NET, not Node.js.
csv.read_csv() is pandas, not Python's csv module.

Writing these is not minimal code — it is confident garbage.

Framework confusion. Every framework has a twin that sounds like it:

render_template (Flask) vs render() (Django)
useForm() (react-hook-form) vs nothing built into React
app.listen() (Express) vs server.listen() (raw Node.js http)

Deprecated APIs. Writing a deprecated method is writing code that will break on the next upgrade.

Show full SKILL.md (204 more words)Show less

Workflow

Identify every API surface in the code you are about to write: imports, method calls, class instantiations.
Verify each one against the user's stated version. If no version is stated, ask once.
Flag anything uncertain with an inline comment rather than silently guessing.
Prefer verbose-but-correct over terse-but-wrong.

When you are not sure if a method exists, annotate it inline:

// verify fs.openAsBlob exists in your Node.js version (>= 20.0)
const blob = await fs.openAsBlob(path);

One comment costs nothing. A silent wrong call costs an hour of the user's time.

If the uncertainty is too high to write correct code without guessing, say:

"I'd need to check whether X exists in version Y before using it. What version are you on?"

Anti-Patterns

Anti-Pattern	What to do instead
Writing a method call you vaguely remember	Stop and verify the exact signature
Silently using a deprecated API	Use the current API and note the deprecation
Assuming API parity across frameworks	Explicitly name the framework and version
Guessing import paths	Check the package's actual export structure
Using an API from a different language's stdlib	Verify it exists in this language
Writing "it should work" without checking	Ask what version the user is on

Cross-References

Related: engineering/minimalist — use together: minimalist reduces code volume; strict-api ensures what is written is correct.
Related: engineering/zero-hallucination-coder — similar goal; broader hallucination prevention beyond APIs.
Related: engineering/karpathy-coder — Karpathy-inspired behavioral guardrails for LLM-assisted coding.

Files

Just SKILL.md in engineering/strict-api of alirezarezvani/claude-skills.

Open the folder on GitHubat commit 19392f7

Compare with similar skills

Strict API 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.

Strict API compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Strict API this skillalirezarezvani/claude-skills	28k	—	~836	Automated safety check: Pass	MIT	1 mo ago
Electron Multi-Process ArchitectureiOfficeAI/AionUi	33k	1 repos	~1.8k	Automated safety check: Pass	Apache-2.0	28 days ago
Generate Release Notesteambit/bit	18k	—	~2.2k	Automated safety check: Pass	Custom licence	yesterday
Code Simplification for ego-litecitrolabs/ego-lite	17k	—	~1.2k	Automated safety check: Pass	MIT	14 days ago
Review Implement Phaseprisma/orm	48k	—	~1.7k	Automated safety check: Pass	Apache-2.0	yesterday
Release Skillsnexmoe/eve	421	3 repos	~3.3k	Automated safety check: Pass	None	6 mo ago

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Works with

Node.js

Questions about Strict API

What does Strict API do?

A skill your agent uses when the user says 'no hallucinations', 'verify APIs', 'reality check', or 'don't invent functions'. Strict API is an agent skill from alirezarezvani/claude-skills. Use when the user says 'no hallucinations', 'verify APIs', 'reality check', or 'don't invent functions'.

When should I use Strict API?

Strict API fits situations like: the user says no hallucinations; dont invent functions.

How do I install Strict API in Claude Code?

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

How do I install Strict API in Codex?

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

Can I use Strict API 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 alirezarezvani/claude-skills --skill strict-api -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/strict-api, .gemini/skills/strict-api, .github/skills/strict-api and .opencode/skills/strict-api in your project.

What does Strict API need to run?

SKILL.md names no scripts, command-line tools or credentials: Strict API is instructions for the agent only. Our summary lists: Node.js.

Does Strict API 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 Strict API 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 Strict API use?

Strict API 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 Strict API use?

About 836 tokens (SKILL.md is roughly 3.3k 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 Strict API?

Skills that share tags, products or a category with Strict API: Electron Multi-Process Architecture (iOfficeAI/AionUi, 33k stars), Generate Release Notes (teambit/bit, 18k stars), Code Simplification for ego-lite (citrolabs/ego-lite, 17k stars) and Review Implement Phase (prisma/orm, 48k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Strict API?

alirezarezvani (a GitHub user) maintains it in alirezarezvani/claude-skills, which has 27,788 GitHub stars. The repository holds 342 skills in this directory. The repository was last updated on August 30, 2026.

Source: alirezarezvani/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.

Install Strict API

Facts

At a glance

What it does

When your agent uses it

Example prompts

Requirements

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Strict API Verification

Overview

The Only Rule

What This Blocks

Workflow

Anti-Patterns

Cross-References

Files

Compare with similar skills

Similar skills

More from alirezarezvani/claude-skills

Related

Questions about Strict API