# MCP quickstart

Three steps take an agent from no account to a first answer from Arche's MCP
server at `https://api.arche.fi/mcp`: get a key, connect a client, call a tool.

## Get a sandbox key

An agent can open a Free account for its owner and receive a sandbox key in the
same response, with no browser step:

```bash
curl -X POST "https://api.arche.fi/v1/agent/signup" \
  -H "Content-Type: application/json" \
  -d '{"email": "owner@yourcompany.com", "agent_name": "research-assistant"}'
```

The key is returned once as `data.api_key`, so store it at once. A sandbox key
reads the same data as a production key. The owner is emailed and can take the
account over later; see [Agent signup](https://docs.arche.fi/agent-signup). Export the key for the
steps below:

```bash
export ARCHE_API_KEY="ak_test_…"
```

## Connect Claude Code

```bash
claude mcp add --transport http arche https://api.arche.fi/mcp \
  --header "X-Api-Key: $ARCHE_API_KEY"
```

Then ask Claude something the tools answer, for example "What were Apple's
total assets on its latest balance sheet, and which filing are they from?"

## Connect Cursor

Add the server to `~/.cursor/mcp.json`, or to `.cursor/mcp.json` in a project:

```json
{
  "mcpServers": {
    "arche": {
      "url": "https://api.arche.fi/mcp",
      "headers": { "X-Api-Key": "YOUR_API_KEY" }
    }
  }
}
```

Keep the key out of configuration you commit.

## Call it over HTTP

Any HTTP client can call the server with JSON-RPC 2.0. Resolve a ticker:

```bash
curl -X POST "https://api.arche.fi/mcp" \
  -H "X-Api-Key: $ARCHE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": {"name": "companies_resolve", "arguments": {"ticker": "AAPL"}}}'
```

The result's `content[0].text` holds the tool's JSON output, here Apple's CIK,
`0000320193`. Pass that CIK to `financials_get_as_of_snapshot` to read its
statements as they were known on a date, with a `replay_token` that
`replay_verify` checks later.

## Next

- [MCP](https://docs.arche.fi/mcp): every tool, its arguments and plan, errors and limits.
- [Python SDK](https://docs.arche.fi/sdks/python): the same data from Python.
- [Verifiable agent answers](https://docs.arche.fi/guides/verifiable-agent-answers): have an agent
  cite and verify what it read.