MCP Gateway

One Model Context Protocol endpoint for 139 tools across 16 MCP servers — public data APIs for research, finance, weather and software, billed at $0.0001 per tool call.

Connect an agent Browse the catalog API

Tools
139
MCP servers
16
Per call
$0.0001
Subscription
None

What is an MCP gateway?

The Model Context Protocol (MCP) is an open standard that lets an AI agent discover and call tools without bespoke integration code for each one. An MCP gateway sits in front of many MCP servers and gives an agent a single endpoint: it routes each tool call to the right upstream server, and handles the cross-cutting concerns — authentication, rate limiting, metering and billing — in one place rather than in every server.

Without a gateway, an agent that needs papers from arXiv, filings from SEC EDGAR and forecasts from the National Weather Service has to find, install, run and keep up to date three separate MCP servers, each with its own credentials and quota. With one, it connects once and calls any of them by name.

This gateway adds two things most do not: it meters every call so you pay only for what you use, and it verifies each provider's terms before listing it, so nothing here is served in breach of the upstream's rules.

MCP gateway pricing

$0.0001 per tool call. No subscription, no monthly minimum, no seat licence. Discovery is free: listing tools, reading this documentation and querying the registry never cost anything. You are charged only when a call reaches an upstream provider and comes back with a result, and a call that fails in transit is refunded automatically inside the same request.

Billing is prepaid credits drawn down per call, tracked in whole micro-dollars (1 µUSD = $0.000001) in an append-only ledger, so nothing is rounded away. A call your balance cannot cover is refused with HTTP 402 before any provider is contacted.

How per-call pricing compares
ModelTypical costCommitment
This gateway$0.0001 per callNone, prepaid credits
Subscription MCP servers$19–$149 per monthMonthly, per server
Self-hostingYour own infrastructureRun and update each server

How to connect

The gateway speaks MCP over Streamable HTTP and supports both the stateless 2026-07-28 revision and the older initialize handshake, so current and older clients both work.

POST https://gateway.mcpharbor.dev/mcp
Authorization: Bearer <your gateway API key>
Content-Type: application/json
Accept: application/json, text/event-stream
MCP-Protocol-Version: 2026-07-28

Point a client at https://gateway.mcpharbor.dev/mcp for every tool, or at https://gateway.mcpharbor.dev/mcp/<server> to narrow it to one provider. The full connection, billing and error-handling contract is in agent.txt, written for an agent to read unaided.

MCP servers in this gateway

Every entry below is live right now. The list is generated from the catalog on each request, so a provider that has been delisted disappears from this page at the same moment it stops being routable.

The same catalog is served as a standard MCP Registry API, so other registries and clients can consume it with ordinary tooling.

Every provider's terms are checked first

An API is listed here only if its terms permit commercial use and permit us to call it on behalf of paying third parties. That rules a lot out: several of the best-known “open” APIs explicitly forbid this model — some require every end user to hold their own key, others name API resellers as prohibited, and several free tiers are licensed for non-commercial use only. Open content does not imply an open pipe.

Where terms permit part of an API but not the rest, the individual tools are excluded rather than the whole server. Each entry records the terms URL, the date we checked and the decisive clauses, and a verdict that goes stale is delisted automatically rather than being served on an assumption.

The verdict for every provider we evaluated, including the ones we rejected and why, is published in the per-server documentation and in the project's compliance record.

For agents and crawlers