An authentication and access-control toolkit for TypeScript applications, covering ways users sign in and what they are allowed to do.

Use it to add email and password accounts, email verification, sign-in with services such as Google or GitHub, two-step verification, and passkeys.

It provides common account and sign-in mechanisms without requiring you to build each one yourself.

How mrgoonie/claudekit-skills configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to mrgoonie/claudekit-skills. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/mrgoonie/claudekit-skills/main/.claude/skills/better-auth/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/mrgoonie/claudekit-skills

Made for: Claude Code.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/mrgoonie/claudekit-skills/better-auth/github.svg)](https://agentmods.dev/skills/mrgoonie/claudekit-skills/better-auth)

Your own site

<a href="https://agentmods.dev/skills/mrgoonie/claudekit-skills/better-auth"><img src="https://agentmods.dev/badge/skills/mrgoonie/claudekit-skills/better-auth/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/mrgoonie/claudekit-skills/better-auth"><img src="https://agentmods.dev/badge/skills/mrgoonie/claudekit-skills/better-auth.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 111 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,699 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits

Socket pass 18 Mar 2026
Snyk pass 15 Feb 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.

Model	Per session	Once invoked
Fable 5.1	$0.00111	$0.01699
Opus 5.5	$0.00044	$0.00680
Sonnet 5.5	$0.00022	$0.00340
Haiku 4.5	$0.00011	$0.00170

Measured 2mo ago against content hash bdf843e14e06, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

better-auth scanned grade A with 0 findings 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 2mo ago.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/better_auth_init.py, scripts/tests/test_better_auth_init.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/better-auth/SKILL.md · 205 lines

The source is not reproduced here

No licence file

Read it on GitHub

Files

What ships with it

9 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.

2mo ago First seen · 205 lines · 111 tokens per session scan A bdf843e14e06

Subscribe to this mod's changes

better-auth is a skill published in the GitHub repository mrgoonie/claudekit-skills (2,235 stars, last pushed 7mo ago), with no licence file. It adds 111 tokens to every session and 1,699 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Backend and APIs Security

better-auth next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
better-authmrgoonie/claudekit-skills	Skill	2.2k	7mo ago	none	A	111	Claude Code
mem0-oss-to-platformmem0ai/mem0	Skill	68k	2d ago	Apache-2.0	A	217	Claude Code, Codex
azure-mgmt-botservice-dotnetmicrosoft/skills	Skill	3.2k	yesterday	MIT	A	78	Claude Code
fastapi-router-pymicrosoft/skills	Skill	3.2k	yesterday	MIT	A	46	Claude Code
dev-runtimelangwatch/langwatch	Skill	5.0k	yesterday	Apache-2.0	A	172	Claude Code
api-designericrisco/rsc-harness	Skill	503	2d ago	MIT	A	105	Claude Code, Codex
migrate-segw-to-raparc-mcp/arc-1	Skill	252	yesterday	MIT	A	106	Claude Code

claudekit-skills: Skill for Claude Code