Check the MCP insideCursor, Claude, VS Codethe way each host connects.

We walk the same MCP URL as each named host you switched on, through handshake, catalog, call, and the job. One check counts as one run, not one per app.

Cover your blind spots

Same server

3 hosts

Cursor

Connected, listed tools, completed the call.

Held

VS Code

Connected and listed tools. Call died.

Broke

Copilot

No session. The host never got in.

No answer

Hosted Claude and ChatGPT stay off the ledger until login walks are honest.

The host is the test.

Green means the server delivered as that host. It does not mean the host chose the tool. Hosted Claude and ChatGPT stay off the ledger until login walks are honest.

Handshake

Did this host get in.

ConnectOK

CursorREACHED

VS CodeREACHED

CopilotNO ANSWER

Connects

Whether this host established a network connection to the server.

AuthHEADER

RequirementHEADER

Cursor sentYES

Copilot sentNO

Authorization

Open, configured header, or OAuth sign-in. We do not complete a user's login inside the host.

initialize

initialize → host profile

accepted

Starts up

Whether the server accepted this host's MCP version and completed initialization.

Tools

Listed is not called. Called is not the job.

CatalogPER HOST

Cursor20 TOOLS

VS Code20 TOOLS

CopilotHIDDEN

Finds tools

After startup, the host requests tools/list. Then we check whether catalog size hid any tools.

fetch

tools/call → fetch

called

Completes the call

A complete JSON-RPC result for tools/call, the requested data, and the published output shape.

search → fetch → writePATH

Completes the workflow

Each ID passed from its source step into its destination step. A broken chain stops where it breaks.

Why hosts differ

Same server. Different client name, protocol, and catalog filter.

IdentityNAME

CursorACCEPTED

VS CodeREFUSED

Client name

The host announces itself. A server that allowlists Cursor can refuse VS Code.

ShownFILTER

Advertised20

Cursor saw20

Copilot saw8

Catalog filtering

Hosts cache, rename, and hide tools before the model sees them. We are not inside the host UI.

VerdictHONEST

Server deliveredYES

Host chose itUNKNOWN

User signed inNOT US

What a green row means

The server delivered as this host. It does not mean the host chose to use that tool.

FAQ

Common questions

Question	Answer
Are you inside Cursor or Claude?	No. We present that host's name, protocol, and whether it can send a configured header. We do not see the user's prompt or which tool the model picked.
Which hosts are on the ledger?	Sixteen named hosts, including Cursor, VS Code, Copilot, Claude Code, and Codex. Hosted Claude and ChatGPT stay off until login walks are honest.
Is this the same as Connection?	No. Connection opens the server as AgentStatus. Host Compatibility opens it as each named host. Named-host rows do not replace the Connection result.
How are runs counted?	One Host Compatibility check is one run, not one run per host. Duration is the wall-clock of that fan-out.

Your biggest blind spots sit outside your logs,inside hosts you don't control.

Paste the MCP URL. We walk named hosts from home internet. Reviewable record, not a status ping.

Cover your blind spots