recon-kit-mcp 0.9.0

An MCP server that gives AI coding agents (Claude Code, Codex, Cline) safe, structured network & security reconnaissance tools — DNS, WHOIS, TLS, HTTP headers, and port scanning. For authorized testing and education only.

recon-mcp

English | 繁體中文

An MCP server that gives AI coding agents — Claude Code, Codex, Cline, and any MCP client — safe, structured network and security reconnaissance tools.

Most MCP servers wrap CRUD APIs. recon-mcp instead exposes the kind of read-only recon an engineer reaches for when investigating an asset, and returns clean JSON — with a graded verdict — so the agent can reason over results instead of parsing console output.

⚠️ Authorized use only. These tools are for security testing of assets you own or have explicit written permission to assess, for CTF practice, and for education. Do not point them at third-party infrastructure without authorization. You are responsible for how you use this software.

Tools

Tool	What it does
recon_report	Start here. One call → DNS, TLS, and HTTP headers checked together, with an overall grade
dns_recon	DNS + WHOIS + email security (SPF/DMARC/DKIM), graded
subdomain_enum	Discover subdomains via DNS brute-force and/or Certificate Transparency logs
subdomain_takeover	Check subdomains for a dangling-CNAME takeover risk against known services
tls_check	Certificate, protocols, ciphers, and known TLS vulnerabilities, graded
http_headers_audit	HTTP security headers (CSP, HSTS, X-Frame-Options, …), graded
cookie_audit	Redirect chain + cookie flags (Secure / HttpOnly / SameSite), graded
cors_check	CORS policy probe — flags arbitrary-Origin reflection and wildcard misuse
well_known_audit	Fetches & parses security.txt (RFC 9116) and robots.txt
ip_info	Resolves the host and enriches its IP via RDAP (owner, country, CIDR, abuse)
port_scan	TCP port scan of one host (≤1024 ports/call), open ports + services

Example

Just ask your agent: "run a security recon report on example.com." It calls recon_report once and gets a graded overview it can act on:

{
  "domain": "example.com",
  "overall_grade": "F",
  "summary": "Overall posture F: email A, TLS B, headers F; 13 actionable issue(s).",
  "components": {
    "email":   { "grade": "A", "issues": [] },
    "tls":     { "grade": "B", "issues": [] },
    "headers": { "grade": "F", "issues": [
      { "severity": "high", "label": "Missing Content-Security-Policy", "detail": "CSP not set; cannot restrict resource load sources" }
    ] }
  }
}

Need more detail on one area? The agent can call dns_recon, subdomain_enum, subdomain_takeover, tls_check, http_headers_audit, cookie_audit, cors_check, well_known_audit, ip_info, or port_scan directly.

Install

Requires Python ≥ 3.10. Runs on Linux, macOS, and Windows (tested in CI).

Recommended — no clone, via uv:

uvx recon-kit-mcp

Or from source (for development):

git clone https://github.com/nan786521/recon-mcp
cd recon-mcp
python -m venv .venv
# Windows
.venv\Scripts\activate
# macOS / Linux
source .venv/bin/activate
pip install -e .

Use with Claude Code

Add the server (stdio transport). With uvx you don't need an absolute path:

claude mcp add recon -- uvx recon-kit-mcp

Or add it manually to any MCP client config:

{
  "mcpServers": {
    "recon": {
      "command": "uvx",
      "args": ["recon-kit-mcp"]
    }
  }
}

(From a source checkout, point the command at /absolute/path/to/.venv/bin/recon-kit-mcp instead.)

Then just ask: "run a security recon report on example.com" — or target one area, e.g. "check the email security of example.com."

The server also ships a security_recon prompt: pick it from your client's prompt menu and pass a domain for a guided, severity-sorted audit.

Tool reference

recon_report(domain, timeout?) -> dict

Runs DNS/email, TLS, and HTTP-header checks together and returns overall_grade (as weak as the weakest component), a one-line summary, and components (email / tls / headers), each with its grade and actionable issues. Uses a fast single-handshake TLS check for speed — call tls_check for the full cipher/vulnerability analysis. The best starting point; use the tools below for raw detail.

dns_recon(domain, checks?, timeout?) -> dict

• records — A, AAAA, MX, NS, TXT, SOA, CNAME, CAA records
• whois — parsed registration fields + raw WHOIS text
• email — SPF, DMARC, and DKIM posture, plus a graded assessment (letter grade A–F, a summary, and per-check findings with severity and a recommended fix)

checks is any subset of ["records", "whois", "email"]; omit it to run all.

subdomain_enum(domain, wordlist?, source="dns", timeout?) -> dict

Discovers subdomains from two complementary sources:

• source="dns" (default) — resolves candidate labels via DNS. wordlist is comma-separated labels ("www,api,dev"); omit it for a built-in common list. Capped at 512 candidates per call. Returns resolved ips.
• source="ct" — queries public Certificate Transparency logs (crt.sh) for every name ever certified for the domain. Fully passive; finds real hosts no wordlist would guess.
• source="both" — runs both and merges, recording which source(s) saw each host.

Returns sources, found_count, and found (each with subdomain, the sources that saw it, and ips when resolved).

subdomain_takeover(hosts, timeout?) -> dict

Checks subdomains for a dangling-CNAME takeover — a subdomain that CNAMEs to a third-party service (GitHub Pages, S3, Heroku, Azure, Fastly, Shopify, …) whose resource was deleted or never claimed, letting anyone who registers that resource serve content on the victim's subdomain. For each host it resolves the CNAME, recognizes known takeover-prone services, fetches the page, and flags the provider's "unclaimed resource" fingerprint and/or a CNAME target that no longer resolves. hosts is one hostname or a comma-separated list (capped at 100). Read-only — DNS lookups plus one HTTP GET per host. Pair it with subdomain_enum: enumerate first, then check the interesting hosts.

Returns checked, vulnerable_count, and results (each with host, cname, service, status, vulnerable, severity, and detail). status is one of not_applicable, not_vulnerable, potential, dangling_cname, or vulnerable.

tls_check(host, port=443, timeout?) -> dict

Returns grade, certificate (validity / expiry / key algorithm), protocols (flags legacy SSLv3 / TLS 1.0 / 1.1), cipher info, forward_secrecy, hsts, vulnerabilities (each with a vulnerable flag), and a findings list.

http_headers_audit(host, port?, use_ssl=True, timeout?) -> dict

Returns grade, score, the observed security headers, and a findings list with a recommendation per header. Defaults to HTTPS (port 443).

cookie_audit(host, port?, use_ssl=True, timeout?) -> dict

Follows the redirect chain from the host (capped at 10 hops, flagging any HTTPS→HTTP downgrade) and audits every Set-Cookie seen for the Secure, HttpOnly, and SameSite flags. Returns redirect_chain, final_url, cookies (flags only — values are never returned), cookie_grade, cookie_score, and a findings list.

cors_check(host, port?, use_ssl=True, timeout?) -> dict

Sends one GET with an untrusted Origin and inspects the Access-Control-Allow-Origin / -Allow-Credentials response. Reflecting an arbitrary Origin with credentials is high severity (any site can read authenticated responses); a wildcard or trusted null origin are lesser issues. Returns acao, allows_credentials, reflects_origin, wildcard, severity, and findings.

well_known_audit(host, timeout?) -> dict

Fetches and parses security.txt (RFC 9116, tried at /.well-known/ then the legacy path) and robots.txt. Returns security_txt (parsed fields, structural issues, location) and robots_txt (sitemaps, disallow/allow paths, user_agents), each with a present flag.

ip_info(host, timeout?) -> dict

Resolves the host's IP and looks it up in the public RDAP registry (via rdap.org's bootstrap to the right RIR). Returns ip and rdap (handle, name, country, cidr, org, abuse_email).

port_scan(host, ports?, timeout?) -> dict

TCP connect scan of a single host. ports is a string — "22,80,443", a range "1-1024", or a mix — and omitting it scans a built-in common-port set. Hard-capped at 1024 ports per call (single-host recon, not mass scanning). Returns host, ip, scanned, open_count, and open_ports (port + service). Scan only hosts you are authorized to assess.

License

MIT