Cursor - Niadra

Cursor connects to MCP servers over Streamable HTTP and takes headers in mcp.json, with environment variables interpolated as ${env:NAME}. Use a key of the sandbox space (nia_sk_test_...), never a live one.

What the connection needs

Header	Value	Where it comes from
`Authorization`	`Bearer` and the source key	The Console, under Agents and keys, in the sandbox space
`Niadra-Subject-Token`	A signed token that binds the connection to a test customer	`POST /v1/subject-tokens`, with the same key; valid for 15 minutes

Connect

In .cursor/mcp.json in the project (or ~/.cursor/mcp.json for every project):

{
  "mcpServers": {
    "niadra": {
      "url": "https://acme-sandbox.us-east-2.api.niadra.com/mcp",
      "headers": {
        "Authorization": "Bearer ${env:NIADRA_API_KEY}",
        "Niadra-Subject-Token": "${env:NIADRA_SUBJECT_TOKEN}"
      }
    }
  }
}

Export NIADRA_API_KEY and NIADRA_SUBJECT_TOKEN in the environment Cursor is opened from, and turn the server on under Cursor Settings > MCP. The tools become available to Cursor’s agent; with agent memory on in the space, search_agent_memory (and remember, with the agent_memory:write scope) show up next to the seven customer tools.

Limits

The token lasts 15 minutes: once it expires, the customer tools answer unauthenticated. Mint another, update the variable and reload the server. The two agent memory tools work without a token.
The customer is always the token’s. The server answers POST only.
Every tool call leaves a receipt in the space.

Next steps

MCP with any LLM

the tools, the token and what each one requires.

Coding assistants

the skill that teaches Cursor to connect a repository to Niadra.