Frontmcp Auth UI

What it does

When your agent uses it

• Replacing the built-in FrontMCP OAuth pages (the login
• Federated-select
• Incremental-authorization
• Error pages) with your own React components

Example prompts

• “/frontmcp-auth-ui”

Requirements

• Node.js

Workflow steps

5 steps, taken from the first numbered list in SKILL.md.

1. 1Write a React component (default export) for the slot, reading the injected state via @frontmcp/ui/auth hooks (see…
2. 2Map the slot to its .tsx path under auth.ui — a RELATIVE path auto-anchored to the config file's directory (no fileURLToPath)
3. 3(Optional) Add an auth.extras[name] handler function for any mid-flow validated field
4. 4Declare both under auth: @FrontMcp({ auth: { mode: 'local', ui: { login: './…' }, extras: { … } } }) (per-app under splitByApp — put them…
5. 5Verify using the Verification Checklist below

What it can do on your machine

Read from SKILL.md and the folder at commit 8f59ba8. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • npm

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Hosts in commands or code, which the agent is likely to contact:

  • esm.sh

  Also links to:

  • docs.agentfront.dev

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Frontmcp Auth UI loads about 3.7k tokens when it runs, and up to ~7.9k if it reads all its reference files. Until then it costs about 207 tokens; SKILL.md has 1,172 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~207

When it runs · the whole SKILL.md, loaded when a task matches

~3.7k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~7.9k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from agentfront/frontmcp at commit 8f59ba8, republished under its Apache-2.0 licence (© agentfront). 1,172 words, ~3,704 tokens.

name

frontmcp-auth-ui

description

Use when customizing, branding, or replacing the built-in FrontMCP OAuth pages (the login, consent, federated-select, incremental-authorization, and error pages) with your own React components. Covers the auth.ui slot-to-file map and auth.extras name-to-handler map on the auth config (no decorator, no class); the @frontmcp/ui/auth React hooks, the AuthPageWrapper component, and mountAuthPage (client-rendered via an esm.sh import-map plus a per-file server-side transform, with no bundling and no SSR); and the framework-owned CSRF and CSP. Triggers: custom login page, brand the consent screen, replace the OAuth UI, custom authorization UI, style the auth pages, multi-step login. The skill for CUSTOM AUTHORIZATION UI (distinct from auth config in frontmcp-config and permissions in frontmcp-authorities).

tags

auth, auth-ui, login, consent, custom-ui, react, oauth, guide

category

config

targets

all

bundle

full

priority

5

visibility

both

license

Apache-2.0

metadata.docs

https://docs.agentfront.dev/frontmcp/authentication/custom-ui

// src/server.ts
import { App } from '@frontmcp/sdk'; // or @FrontMcp

@App({
  auth: {
    mode: 'local',
    // slot → RELATIVE .tsx, auto-anchored to THIS config file's directory.
    ui: { login: './auth/login.tsx' },
    // extra name → handler fn (no class).
    extras: { 'envs:add': async (input, ctx) => ({ ok: true, addedItems: [{ key: String(input.key) }] }) },
  },
})
export default class Server {}

© agentfront, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 3 other files (references) in libs/skills/catalog/frontmcp-auth-ui of agentfront/frontmcp.

• SKILL.md
• examples/custom-auth-ui/login-slot.md
• examples/custom-auth-ui/multi-step-auth-extra.md
• references/custom-auth-ui.md

Open the folder on GitHubat commit 8f59ba8