core-data

core-data is a skill for Claude Code from dpearson2699/swift-ios-skills. It costs 130 tokens per session (3,635 once invoked), scanned A, original, no licence file.

A guide to storing and querying app data with Core Data, Apple's persistence framework for apps that use managed objects instead of SwiftData.

In plain words
What is it for?
Use it for NSManagedObject models, fetched-result-driven lists, bulk inserts, deletes or updates, and persistent change-history processing.
Why use it?
It helps manage database-like data, list updates, large changes, and history tracking without designing every persistence operation yourself.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the swift-core-skills plugin — 10 skills shipped together , and of all-ios-skills

Good fit Use it for NSManagedObject models, fetched-result-driven lists, bulk inserts, deletes or updates, and persistent change-history processing.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/dpearson2699/swift-ios-skills/core-data
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add dpearson2699/swift-ios-skills --skill core-data
Clone the repo
git clone --depth 1 https://github.com/dpearson2699/swift-ios-skills

Made for: Claude Code.

Or install swift-core-skills, the plugin that ships this one along with the rest of its 10 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for core-data

README.md
[![agentmods](https://agentmods.dev/badge/skills/dpearson2699/swift-ios-skills/core-data.svg)](https://agentmods.dev/skills/dpearson2699/swift-ios-skills/core-data)
Your own site
<a href="https://agentmods.dev/skills/dpearson2699/swift-ios-skills/core-data"><img src="https://agentmods.dev/badge/skills/dpearson2699/swift-ios-skills/core-data.svg" alt="Measured on agentmods" height="20"></a>
Per session 130 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,635 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 23 Apr 2026
  • Snyk pass 23 Apr 2026
How audits are shown
Origin unknown No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00130 $0.03635
Opus 5 $0.00065 $0.01818
Sonnet 5 $0.00026 $0.00727
Haiku 4.5 $0.00013 $0.00364

Measured 8d ago against content hash be0f9b2bc5f9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

core-data scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

let trips = try context.fetch(request)
skills/core-data/SKILL.md · 414 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 8d ago First seen · 414 lines · 130 tokens per session scan A be0f9b2bc5f9

Subscribe to this mod's changes

core-data is a skill published in the GitHub repository dpearson2699/swift-ios-skills (1,086 stars, last pushed 1mo ago), with no licence file. It adds 130 tokens to every session and 3,635 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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