challenge
Get details for a specific challenge by name or ID.
LABSCO SUMMARY
The instance is a runtime setting, not a config file edit.
CTFs come and go weekly, and the base URL, the token and the cookie can all be set from inside the session — so joining a new event does not mean restarting a client. The read side is the useful half: challenges and progress in the same place as the work.
What it is
A client for any CTFd instance. It authenticates three ways, lists and opens challenges, submits flags, and reports where you stand — with the target instance set at runtime rather than baked in.
What you get
- The base URL set from inside the session, so one install works across events
- Three ways in: an API token, a session cookie, or a plain username and password login
- Challenges listed, optionally narrowed to one category, and any of them opened by name or by ID
- Flags submitted against a challenge identified either way
- The scoreboard, and your own solves and progress
- A health check on the connection, for when something stops answering mid-event
Requirements
Node, run over stdio from npm as ctfd-mcp-server through npx or a global install. Point it at a CTFd instance with BASE_URL and give it a credential — CTFD_TOKEN in the environment, or a cookie or username and password supplied in the session. It is validated against the official demo instance at https://demo.ctfd.io.
Setup effort
One command plus a key — npx ctfd-mcp-server, then supply credentials
USE CASES
01
Joining an event that just started
Point the server at the instance and authenticate with whichever credential you have — token, cookie or login.
02
Picking what to work on
List the challenges in the category you are strongest in, then open the promising ones for their full text.
03
Submitting a flag you just cracked
Send it against the challenge by name or ID and read whether it was accepted.
04
Seeing where the team stands
Read the scoreboard and your own solves together, so effort goes where the points still are.
05
Working out why nothing is responding
Check the connection health before assuming the platform is down or the session has expired.
10 tools
Counted once with only startup setup. Other versions, modes or optional credentials may expose a different list.
challenges
List all challenges from CTFd, with optional category filter.
health
Check health status of the CTFd connection.
login
Login to CTFd with username and password.
progress
Get the current user's progress and solves.
scoreboard
Get the CTFd scoreboard.
set_base_url
Set the base URL for the CTFd instance.
set_cookie
Set session cookie for CTFd authentication.
set_token
Set authentication token for CTFd API.
submit_flag
Submit a flag for a challenge.
BEFORE YOU INSTALL
What to know first
Tools you get
10 tools when we connected. set_base_url, set_token, set_cookie and login configure the server mid-session rather than exposing CTFd features; submit_flag is the tool that scores.
Requires
- npx on PATH
- CTFD_TOKEN in your environment
Where it runs
All 4 documented clients run the server on your machine.
CONTEXT COST
Light Standing cost
Rated by the size of the 10 tool definitions that ride along on every turn, not by how many there are
INSTALLATION
Connect your client
Server setup
TERMINAL
npx ctfd-mcp-serverMCP Clients
Claude Desktop, Gemini CLI
JSON
{
"mcpServers": {
"ctfd": {
"command": "npx",
"args": [
"-y",
"ctfd-mcp-server"
],
"env": {
"BASE_URL": "https://demo.ctfd.io",
"CTFD_TOKEN": "<YOUR_CTFD_TOKEN>"
}
}
}
}Codex
CODEX · TERMINAL
codex mcp add ctfd -- npx -y ctfd-mcp-serverAmp
AMP · JSON
{
"amp.mcpServers": {
"ctfd": {
"command": "npx",
"args": [
"-y",
"ctfd-mcp-server"
],
"env": {
"BASE_URL": "https://demo.ctfd.io",
"CTFD_TOKEN": "<YOUR_CTFD_TOKEN>"
}
}
}
}
