Free tool

MCP Auth Checker

Connect to your MCP server with no credentials at all and see exactly what it hands over. It is rarely what people assume.

Works with streamable HTTP and SSE endpoints, for example https://mcp.example.com/mcp
This server needs authentication
Used for this one request and never stored.

Working is not the same as sellable

Once the transport is right, the remaining problem is that nobody can see what your server does. MCP Showcase turns the same URL into a live playground with documentation for every tool.

How it works

link
Paste your server URL

Deliberately without a token — that is the test.

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We connect as a stranger would

No credentials, no headers, exactly what someone who found your URL would send.

checklist
See the exposed surface

Which tools are listed, whether anything is served over plain HTTP, and how the surface grades.

What does your server hand a stranger?

This page connects to your MCP server with no credentials — no token, no headers, nothing — and reports exactly what comes back. It is the same handshake and tools/list call any MCP client makes on connecting, so it is traffic your server already accepts from every agent that uses it.

The answer is often not what people expect, because the tool list and the tool calls are usually protected separately, and only the second one gets attention.

Tool names are not nothing

A server that lists its tools anonymously and only rejects the calls has still handed over a map: internal_billing_adjust, prod_db_query, delete_tenant. That is a description of your systems, available to anyone who finds the URL. If the calls are protected, the list usually should be too.

MCP URLs are not secret

They end up in config files, in logs, in screenshots and in support tickets. Treat the endpoint as public and put the control at the server rather than relying on the address being unguessable — it will not stay unguessable.

A token is not the whole answer

A static bearer token authenticates, which is most of the job, but rotation and revocation become yours to handle, and it is only as safe as the transport carrying it. A token over plain HTTP is not protection — it is a credential broadcast to everything on the path, which is why that combination is flagged as critical in the result.

Related tools

The transport is not the hard part

Once a client can reach your server, the remaining problem is that nobody can tell what it does. A tool list is not a demonstration, and a prospect will not install a client to find out. MCP Showcase points at the same URL and produces a live playground with generated documentation for every tool, so evaluating your server takes a click.

Frequently asked questions

For a public read-only server, its tool list is fine and arguably the point. For anything that writes data, spends money or reaches internal systems, an anonymous client should get a 401 and nothing else — including no tool names, since those alone describe your internals.

It authenticates, which is most of the job, but it puts rotation and revocation on you and it is only as safe as the transport carrying it. A token over plain HTTP is not protection; it is a credential broadcast to anything on the path.

It depends entirely on what happens next. MCP endpoints are not secret — they end up in configs, logs and screenshots. Treat the URL as public and put the control at the server.

The OAuth checker is about the discovery flow: whether your server signals its authorization requirements in a way clients can follow automatically. This page is the blunter question of what a stranger gets.

Yes. This does exactly what any MCP client does on connecting — a handshake and a tools/list call — and never invokes a tool. It is the same traffic the server already accepts from every agent that uses it.

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