caddy-security is a security application and set of plugins for Caddy v2, a web server, that handles user authentication and controls access to HTTP requests. It supports methods including local, LDAP, OpenID Connect, OAuth 2.0, SAML, JWT, and PASETO, and is used to protect web services behind Caddy.
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.
npx skills add greenpau/caddy-security --skill configuration-authentication-uigit clone --depth 1 https://github.com/greenpau/caddy-securityWrote 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.
[](https://agentmods.dev/skills/greenpau/caddy-security/configuration-authentication-ui)<a href="https://agentmods.dev/skills/greenpau/caddy-security/configuration-authentication-ui"><img src="https://agentmods.dev/badge/skills/greenpau/caddy-security/configuration-authentication-ui/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.
<a href="https://agentmods.dev/skills/greenpau/caddy-security/configuration-authentication-ui"><img src="https://agentmods.dev/badge/skills/greenpau/caddy-security/configuration-authentication-ui.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00043 | $0.01774 |
| Opus 5.5 | $0.00017 | $0.00710 |
| Sonnet 5.5 | $0.00009 | $0.00355 |
| Haiku 4.5 | $0.00004 | $0.00177 |
Grade A, and why
configuration-authentication-ui 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 today.
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.
How it starts
The opening of the file, as written. The whole thing — 196 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Configuration Authentication UI
Published UI contract
The selected embedded portal and OIDC pages supply their themed layouts and
browser color preference behavior automatically. theme basic remains the
only registered Caddy theme; do not invent theme dark or theme light.
Profile assets include profile/images/banner.svg, favicon.svg and
logo.svg. Custom static PNG assets remain supported. Avoid pinning internal
hashed assets when customizing templates; inspect the selected embedded UI.
Conditional flow selection and profile policy editing need no extra UI setting;
see authentication flows.
Purpose
Use this skill for ui blocks inside authentication portal <name> blocks.
Read these files when details matter:
caddyfile_authn_ui.gofor accepted Caddyfile UI syntax.../go-authcrunch/pkg/authn/ui/params.gofor authcrunch UI parameters.../go-authcrunch/pkg/authn/portal.gofor UI defaults, template loading, static assets, theme and language validation.../go-authcrunch/pkg/authn/ui/static.gofor static asset loading and content-type handling.
The surrounding portal belongs to
configuration-authentication.
Transform-generated ui link entries belong to
configuration-authentication-user-transforms;
they are separate from static links in this UI block.
Supported UI Forms
The Caddyfile ui parser supports templates, metadata, private links, static
assets, themes, languages, logos, auto_redirect_url, and custom CSS,
JavaScript, or HTML-header injection. Use parser-supported forms:
authentication portal myportal {
ui {
theme basic
language en
meta title "Example Authentication Portal"
meta author "Example"
meta description "Example sign-in portal"
template login ui/login.template
static_asset "assets/images/logo.png" "image/png" ui/logo.png
logo url "/auth/assets/images/logo.png"
logo description "Example"
auto_redirect_url /auth/portal
links {
"My Identity" "/auth/whoami" icon "las la-user"
"Docs" "https://docs.example.com/" target_blank
}
}
}
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.
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.
- today First seen · 196 lines · 43 tokens per session scan A 017aaf468ef1
configuration-authentication-ui is a skill published in the GitHub repository greenpau/caddy-security (2,263 stars, last pushed today), licensed Apache-2.0. It adds 43 tokens to every session and 1,774 once invoked, about $0.0002 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 2026-10-25.
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