cryptokit SKILL.md skillA
cryptokit from jordancoin/ios-skills-collection is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add jordancoin/ios-skills-collection/cryptokit@git:20260329.893209fPins git:20260329.893209f in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- jordancoin/ios-skills-collection
- Path
skills/dpearson2699--cryptokit/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260329.893209f, committed Mar 29, 2026
- Size
- 12,235 bytes
- Repository stars
- 6
- License
- a license file GitHub does not identify
Perform cryptographic operations using Apple CryptoKit. Use when hashing data with SHA256/SHA384/SHA512, generating HMAC authentication codes, encrypting with AES-GCM or ChaChaPoly, signing with P256/P384/P521/Curve25519 keys, performing ECDH key agreement, storing keys in the Secure Enclave, or migrating from CommonCrypto to CryptoKit.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# CryptoKit
Apple CryptoKit provides a Swift-native API for cryptographic operations:
hashing, message authentication, symmetric encryption, public-key signing,
key agreement, and Secure Enclave key storage. Available on iOS 13+.
Prefer CryptoKit over CommonCrypto or raw Security framework APIs in all
new code targeting Swift 6.3+.
## Contents
- [Hashing](#hashing)
- [HMAC](#hmac)
- [Symmetric Encryption](#symmetric-encryption)
- [Public-Key Signing](#public-key-signing)
- [Key Agreement](#key-agreement)
- [Secure Enclave](#secure-enclave)
- [Common Mistakes](#common-mistakes)
- [Review Checklist](#review-checklist)
- [References](#references)
## Hashing
CryptoKit provides SHA256, SHA384, and SHA512 hash functions. All conform
to the `HashFunction` protocol.
### One-shot hashing
```swift
import CryptoKit
let data = Data("Hello, world!".utf8)
let digest = SHA256.hash(data: data)
let hex = digest.compactMap { String(format: "%02x", $0) }.joined()
```
SHA384 and SHA512 work identically -- substitute the type name.
### Incremental hashing
For large data or streaming input, hash incrementally:
```swift
var hasher = SHA256()
hasher.update(data: chunk1)
…Read the whole file at its exact version.
How to install
mdr add jordancoin/ios-skills-collection/cryptokit@sha256:1c9aa05e18b55bcfThe line at the top of this page pins the label git:20260329.893209f, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_a4rsa5djm7zbmpmb)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Mar 29, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (12235 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
jordancoin/ios-skills-collection · 6 stars · license a license file GitHub does not identify · pushed 2026-09-10 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_a4rsa5djm7zbmpmb GET https://markdownregistry.com/api/v1/resolve?ref=jordancoin/ios-skills-collection/cryptokit GET https://markdownregistry.com/api/v1/blob/1c9aa05e18b55bcfeefb8440ef8fe4533538a7bb7bf02c7f409c48de1d1e047b
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.