"Free APIs and services without commercial fees" matching MCP servers:

MCP server that exposes Avangenio's service status by fetching and parsing status.avangenio.com/data.txt into normalized JSON.

Enables MCP-compatible clients to list verified free HTTP, SOCKS4, and SOCKS5 proxies, pick top-ranked ones, and summarize the current proxy snapshot through three read-only tools, without forwarding traffic or accepting arbitrary URLs.

Bridge that connects AI assistants to a Netmon appliance, enabling read-only access to devices, interfaces, logs, alerts, and Windows-agent data via MCP tools.

Domain security reconnaissance for AI agents — 13 tools (DNS+DNSSEC, SSL/TLS, HTTP security headers, SPF/DKIM/DMARC email auth, port scan, ASN, RDAP/WHOIS) plus a one-shot security_scan returning a 0–100 Health Score (A–F). Free, no API key.

Self-hostable MCP server for WhisperGraph — a graph of 7.39B nodes / 39B edges mapping DNS, BGP, GeoIP, WHOIS, and threat intelligence. Six read-only tools (Cypher query + schema introspection + threat assessment), six resources, eight investigation prompts. stdio and Streamable HTTP transports.

A read-only MCP server that enables Claude to audit Firewalla network security configurations and monitor network activity. It provides tools to inspect devices, rules, alarms, and traffic flows without making any changes to the Firewalla system.

Uptime monitoring for websites, APIs, SSL certificates, domain expiry, ping and TCP/UDP ports. 15 tools to list, create, pause and delete monitors, pull incident timelines with error codes, and read hourly or daily uptime and response-time statistics.

VMware AVI Load Balancer (NSX Advanced Load Balancer) management plus AKO Kubernetes integration. 29 MCP tools across virtual services, pools, analytics, and AKO lifecycle, with double-confirmation gates and audit logging for destructive operations.

MCP server for IntoDNS.ai providing 36 free tools for DNS, DMARC, SPF, DKIM, BIMI, DNSSEC, MTA-STS, FCrDNS, blacklist and email security checks. Citation-grade report snapshots with content hashes. No API key required.

Enables an LLM agent to investigate a Kong Gateway through fourteen read-only, schema-validated tools and a deterministic diagnostic engine, so it can trace routes, services, plugins and upstream health and explain faults such as why authentication is failing on a path. Every fact comes from the gateway itself, and the model only selects tools and writes the evidence-backed explanation.

MCP server that parses 3GPP .docx specifications into structured sections with full-text search, letting LLMs browse, search, and follow cross-references without a vector database.

Enables LLM agents to read 3x-ui panel data and perform full CRUD operations on inbounds and clients.

Enables querying telecom routing data (LRN, CNAM, DNO, LERG, toll-free routing) directly from AI assistants like Claude, ChatGPT.

MCP server for discovering Kubernetes services and running kubectl port-forward sessions, optionally with separate log windows.

MCP server that exposes mDNS service discovery functionality via the Model Context Protocol, enabling LLMs to discover and query zero-configuration network services on the local network.

An MCP server that lets Claude monitor and manage a TrueNAS box in plain English. It is deliberately read-only, providing tools to check alerts, storage pools, snapshots, services, and more.

MCP server for live IP and domain reputation checks via DNS lookups, providing abuse scores and network type without requiring an API key.

Enables AI agents to explore licensed IP intelligence databases through four read-only tools: listing the databases an organization is licensed for, inspecting a database's columns, sample rows, row count and build date, fetching published checksums for verifying a local copy, and reviewing recent download attempts. It covers VPN, proxy, hosting, CDN and relay address space data without transferring the multi-gigabyte files themselves.

Enables MCP-speaking agents to claim and manage free subdomains under makes.fyi or agentdomains.co, including DNS records, HTTPS, URL forwarding, reverse proxying, and account management.

MCP server that lets AI agents use the Online Cyber Tools catalogue as a set of native MCP tools.