# Cairo Starknet Types

> Explain Starknet-specific types like ContractAddress, StorageAddress, ClassHash, EthAddress, BlockInfo, and TxInfo; use when a request involves these core Starknet types in Cairo.

- Skill: `teddyjfpender/cairo-starknet-types` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add teddyjfpender/cairo-starknet-types`
- Raw SKILL.md: https://api.skillmd.com/api/skills/teddyjfpender/cairo-starknet-types/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: teddyjfpender (https://skillmd.com/u/teddyjfpender)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/teddyjfpender/cairo-starknet-types

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# Cairo Starknet Types

## Overview
Explain the core Starknet types and when to use them instead of raw felt values.

## Quick Use
- Read `references/starknet-types.md` before answering.
- Use explicit type conversions when needed (try_from, into, or constructors).
- Mention range constraints for addresses and hashes.

## Response Checklist
- Use ContractAddress for any contract address parameter or storage.
- Use StorageAddress and StorageBaseAddress for storage slot computations.
- Use ClassHash for class identifiers and EthAddress for L1 addresses.
- Use BlockInfo and TxInfo for environment context.

## Example Requests
- "How do I convert a felt into a ContractAddress?"
- "What is ClassHash used for?"
- "What is the difference between StorageAddress and StorageBaseAddress?"