MCP Server - Validation Cloud

The Validation Cloud MCP server gives AI coding agents access to Mavrik and to your team’s Node API account through the Model Context Protocol. It is a remote server, so there is nothing to install or run locally.


Server URL	`https://mcp.validationcloud.io/mcp`
Authentication	OAuth 2.1 with your Validation Cloud account

Authentication

You connect with your Validation Cloud account. The first time a client connects, it opens a browser window: log in and click Accept on the Authorize App screen. The client stores the token and refreshes it for you.

The Authorize App screen shows a notice like External App - Verify you recognize the domain http://localhost:64483/callback. That address is your MCP client on your own machine, where it receives the login result. Accept it when you started the connection from your client.

Connect your client

The examples name the server validation-cloud; any name works.

Claude Code

claude mcp add --transport http validation-cloud https://mcp.validationcloud.io/mcp

Then run /mcp in Claude Code, select validation-cloud, choose Authenticate and log in. The server is added for the current project; add --scope user to use it in every project.

Codex

Add the server to ~/.codex/config.toml:

[mcp_servers.validation-cloud]
url = "https://mcp.validationcloud.io/mcp"

Then run codex mcp login validation-cloud and log in when the browser opens.

Cursor

Use Install in Cursor, or add the server to ~/.cursor/mcp.json and restart Cursor:

{
  "mcpServers": {
    "validation-cloud": {
      "url": "https://mcp.validationcloud.io/mcp"
    }
  }
}

Then open Customize > MCPs (Settings > Tools & MCP in some versions) and select Connect next to validation-cloud.

VS Code

Requires VS Code 1.101 or later. Use Install in VS Code, or add the server to .vscode/mcp.json:

{
  "servers": {
    "validation-cloud": {
      "type": "http",
      "url": "https://mcp.validationcloud.io/mcp"
    }
  }
}

Start it from MCP: List Servers > validation-cloud > Start Server, then select Allow when VS Code asks to authenticate.

Other clients

Point any client that supports remote MCP servers at https://mcp.validationcloud.io/mcp. The client must support OAuth 2.1 with Dynamic Client Registration. Discovery starts at https://mcp.validationcloud.io/.well-known/oauth-protected-resource/mcp, which names https://auth.validationcloud.io/ as the authorization server.

Check the connection

Ask your agent to call nodeapi.get_health. It returns your team and your role on it:

{
  "status": "ok",
  "team_id": "8b1f2c3e-1d4a-4f6b-9a2e-5c7d8e9f0a1b",
  "role": "admin"
}

Tools

Tool names are the ones the server exposes. Some clients rewrite the dot: Claude Code shows nodeapi.get_account as mcp__validation-cloud__nodeapi_get_account.

Node API

Tool	Arguments	What it returns
`nodeapi.rpc_call`	`endpoint_id`, `body`	Sends a JSON-RPC request or batch through one of your endpoints and returns the node’s response unchanged. Metered in compute units like any request to that endpoint.
`nodeapi.get_health`	none	Your team ID and role.
`nodeapi.get_account`	none	Plan, compute-unit quota, usage this billing cycle, and the cycle’s start and end.
`nodeapi.list_chains`	none	Supported chains and networks, with WebSocket and archive support.
`nodeapi.get_compute_unit_costs`	`chain_network`, for example `base/mainnet`	Compute-unit cost per RPC method for that chain and network.
`nodeapi.list_endpoints`	none	Your team’s endpoints, including API keys and RPC URLs.
`nodeapi.get_endpoint`	`id`	One endpoint, including its API key and RPC URLs.
`nodeapi.get_team_usage`	`from`, `to`, `granularity`	Compute-unit usage for the team.
`nodeapi.get_endpoint_usage`	`id`, `from`, `to`, `granularity`	Compute-unit usage for one endpoint, including deleted endpoints.
`nodeapi.create_endpoint`	`name`, `chain`, `network`	Creates an endpoint. Over your endpoint limit, it is created disabled. Not idempotent: check `nodeapi.list_endpoints` before retrying.
`nodeapi.delete_endpoint`	`id`	Deletes the endpoint and revokes its API key.

Every tool works on every plan except nodeapi.create_endpoint and nodeapi.delete_endpoint, which need the Scale plan. nodeapi.delete_endpoint also needs the team Admin role. On the Free plan, you can still create endpoints manually in the Validation Cloud app. For the usage tools, from (inclusive) and to (exclusive) are RFC 3339 timestamps and default to the current UTC month. granularity is HOUR (up to 7 days), DAY (the default, up to 92 days), WEEK or MONTH (up to 366 days). Endpoint id values, and endpoint_id for nodeapi.rpc_call, are the UUIDs returned by nodeapi.list_endpoints. body is a JSON-RPC 2.0 request object or a non-empty batch.

nodeapi.list_endpoints and nodeapi.get_endpoint return endpoint API keys, so the keys end up in your agent’s context and logs.

Mavrik

Tool	Arguments	What it returns
`mavrik.answerQuestion`	`question`; optional `generateChart`, `generateSummary`	Mavrik’s answer to a question about blockchains and digital-asset markets.

Errors

A failed call returns a tool error whose text is a JSON object:

{ "code": "plan_not_eligible", "message": "writes require the Scale plan" }

Code	Meaning
`unauthorized`	The login is missing or expired. Log in again from your client.
`forbidden`	You aren’t a member of the team, or your role can’t do this (deleting needs Admin).
`plan_not_eligible`	The tool needs the Scale plan.
`invalid_request`	An argument is missing or malformed.
`not_found`	The endpoint doesn’t exist or belongs to another team.
`rate_limited`	Too many calls. Wait `retry_after_seconds`, then retry.
`internal_error`	Something failed on our side. Retry, and contact support if it persists.

Troubleshooting

getaddrinfo ENOTFOUND mcp.validationcloud.io: check the server URL and your network.
The client shows “Needs authentication”: run its login step from Connect your client.
To switch account or team, sign out and log in again: Clear authentication under /mcp in Claude Code, codex mcp logout validation-cloud in Codex, or Sign Out on the server in VS Code.
Cursor login hangs: Cursor receives the login on port 8787, so that port must be free while you log in.

See also Teams and roles for how roles differ.

​Authentication

​Connect your client

​Claude Code

​Codex

​Cursor

​VS Code

​Other clients

​Check the connection

​Tools

​Node API

​Mavrik

​Errors

​Troubleshooting

Authentication

Connect your client

Claude Code

Codex

Cursor

VS Code

Other clients

Check the connection

Tools

Node API

Mavrik

Errors

Troubleshooting