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 authentication-portal-apigit 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/authentication-portal-api)<a href="https://agentmods.dev/skills/greenpau/caddy-security/authentication-portal-api"><img src="https://agentmods.dev/badge/skills/greenpau/caddy-security/authentication-portal-api/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/authentication-portal-api"><img src="https://agentmods.dev/badge/skills/greenpau/caddy-security/authentication-portal-api.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 | $0.00044 | $0.03154 |
| Opus 5.5 | $0.00018 | $0.01262 |
| Sonnet 5.5 | $0.00009 | $0.00631 |
| Haiku 4.5 | $0.00004 | $0.00315 |
Grade A, and why
authentication-portal-api 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 — 263 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Authentication Portal API
Purpose
Use this skill for HTTP/JSON interactions with a configured authentication portal. Surrounding Caddyfile declarations belong to configuration-authentication; route mounting belongs to configuration-http-integrations. These are configuration boundaries, not prerequisites for an HTTP client task.
For user-owned profile keys, legacy PGP/RSA metadata, ownership isolation, and canonical profile identity and transformed-claim isolation, read profile public keys. For conditional login selection, authoritative AMR and profile policy preview/ replacement, read authentication flows. For password/MFA mutations and refresh/OIDC invalidation, read local identity compatibility. For authored schemas, mounted endpoint contracts and wire-format exceptions, read OpenAPI contracts. For encrypted file operations, current local browser-session authority, sharing and client key recovery, read Documents API. For explicit external-account connection, fresh browser proofs and one-use confirmation, read connected accounts.
For the standalone caddy-authenticator CLI, profile configuration, terminal
input and private storage, use the
command maintenance reference.
Keep fresh login delegated to the public authclient package; the command owns
cached-token scheduling and its explicit native refresh request.
Read these files when details matter:
../go-authcrunch/pkg/authn/handle_json_*.gofor JSON handlers and response shapes.../go-authcrunch/pkg/authn/handle_http_*.gofor browser versus JSON behavior.caddyfile_authn.goandcaddyfile_authn_admin_api.gofor admin directives.../go-authcrunch/pkg/authn/admin_api/parser/parser.go,admin_api_config.go,respond_api.go, andhandle_api_private_keys.gofor the admin configuration and authorization boundary (the latter three files are directly underpkg/authn).
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.
- agents/openai.yaml 253 B
- references/admin-api.md 7.3 KB
- references/authentication-flows.md 5.2 KB
- references/browser-refresh.md 12 KB
- references/connected-accounts.md 6.1 KB
- references/documents.md 8.1 KB
- references/native-client.md 15 KB
- references/openapi-contracts.md 5.1 KB
- references/profile-public-keys.md 4.7 KB
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 · 263 lines · 44 tokens per session scan A 140f98e98699
authentication-portal-api is a skill published in the GitHub repository greenpau/caddy-security (2,263 stars, last pushed today), licensed Apache-2.0. It adds 44 tokens to every session and 3,154 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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