# 0x API

> Step-by-step guide for executing token swaps using the 0x API (Swap API v2 and Gasless API v2). Use this skill when a user wants to: swap tokens on any EVM chain (e.g. "swap 0.5 ETH for USDC on Arbitrum", "sell 1000 ARB and get a quote", "how much WBTC for 5000 USDC on Base"); do a gasless swap without holding ETH for gas; integrate 0x into a dApp in TypeScript or Python (permit2 flow, allowanceholder flow); use 0x with a Gnosis Safe or multisig wallet; migrate from 0x Swap v1 to v2; debug 0x API errors like INSUFFICIENTASSETLIQUIDITY or allowance issues; or understand when to use AllowanceHolder vs Permit2. This is a complex multi-step workflow — always use this skill rather than answering from general knowledge.

## Facts
- Page: https://tashan.sh/capability/skill-0xproject-0x-api
- tashan id: skill:0xProject/0x-api
- Source: https://github.com/0xProject/0x-ai
- Type: skill
- Category: other
- tashan score: not scored (catalogued only — too little public evidence)
- Adoption: 9.0
- Upkeep: not measured
- Freshness: not measured
- Evidence coverage: not measured
- Health: not measured
- Instruction depth: not yet graded
- Official: no

## Install

```sh
cp -r 0x-api ~/.claude/skills/
```

## Security audit
Not scanned. We audit npm-published capabilities; this one has no npm package we can resolve, or has not reached the queue. This is not a clean bill of health.

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Measured 2026-08-14 by tashan (https://tashan.sh) from public evidence. Scorer s5.