Nyx Developer Platform
Build on the crypto fund back office
A read-only Fund Data API, illustrative calculator endpoints, and a public MCP server — the same engines that run the Nyx Fund dashboard.
Twelve read-only, GET-only endpoints over your live shadow ledger — positions, NAV, exposure, risk, and fees.
- · Bearer-key auth, one header
- · Same money precision as the dashboard
- · Redacted at the edge, fail-closed
Seven stateless, illustrative fund-math endpoints — no auth, no fund required, deterministic in and out.
- · Fee, NAV, exposure, and cost-savings math
- · The same engines that power /tools
- · Free — 500 requests/day, no card
A public MCP server so Claude Code, Claude Desktop, Cursor, and any JSON-RPC client can call the same calculators.
- · One-command install
- · No key required for the public server
- · A fund-scoped server for real fund data
Install in your agent
One command, and your agent can query fund calculators
Claude Code
Add the Nyx Fund public MCP server with one `claude mcp add` command.
claude mcp add --transport http nyx-fund https://nyxchain.org/api/mcp/publicClaude Desktop
Paste a custom connector entry into your Claude Desktop config.
{
"nyx-fund": {
"type": "http",
"url": "https://nyxchain.org/api/mcp/public"
}
}Cursor
Install via a one-click deeplink, or paste the config JSON yourself.
{
"mcpServers": {
"nyx-fund": {
"url": "https://nyxchain.org/api/mcp/public"
}
}
}ChatGPT
Add as a custom connector where your ChatGPT plan and workspace support MCP.
ChatGPT's MCP connector support (Settings, Connectors, Add custom connector — on plans and workspaces where it's enabled) accepts an HTTP MCP server URL:
https://nyxchain.org/api/mcp/public
If a header is required, add it as a custom header: "Authorization: Bearer <your API key>". Availability depends on your ChatGPT plan and workspace configuration.Any MCP client (JSON-RPC)
Speak raw MCP JSON-RPC over HTTP — works with any spec-compliant client.
# 1. Initialize the MCP session
curl -s -X POST "https://nyxchain.org/api/mcp/public" \
-H "Content-Type: application/json" \
-H "Accept: application/json, text/event-stream" \
-d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2026-06-18","capabilities":{},"clientInfo":{"name":"example-client","version":"1.0.0"}}}'
# 2. Call a tool
curl -s -X POST "https://nyxchain.org/api/mcp/public" \
-H "Content-Type: application/json" \
-H "Accept: application/json, text/event-stream" \
-d '{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"get_fund_overview","arguments":{}}}'Pricing
See full pricing →- · 100k calculator requests included per month
- · then $0.50 per 1,000 requests
- · API keys and a usage dashboard
- · Fund Data API: 250k requests included per month
- · then $0.75 per 1,000 requests
- · Everything in Developer
FAQ
Questions, answered
Is there a crypto fund reporting API?
Yes. Nyx Fund's Developer API is a read-only REST API over Nyx Fund's live double-entry shadow ledger — twelve GET endpoints covering positions, NAV history, exposure, risk (VaR), P&L attribution, trial balance, capital accounts, expenses, and fee terms, plus seven no-auth calculator endpoints for fee and NAV math. Full docs live at nyxchain.org/developers.
Is there a hedge fund NAV API?
Yes. GET /api/v1/fund/nav/history returns Nyx's own shadow NAV history with BTC/ETH reference prices, computed from a real double-entry ledger and reconciled against your fund administrator — it is a shadow book that sits alongside your administrator, not a replacement for one, and requires an Authorization: Bearer nyx_dk_ developer key.
Do I need to sign up to try the Nyx Fund API?
No. A published demo developer key lets you call every Fund Data API endpoint against a synthetic fixture fund with zero signup, and the calculator endpoints need no key at all — see the quickstart at nyxchain.org/developers/quickstart.
What does the Nyx Fund Developer API cost?
Calculator access is free — 500 requests a day, no card required. The Fund Data API is metered: $49 a month for 100k requests (then $0.50 per 1,000), or included with the $999-a-month Nyx Fund platform plan (250k requests, then $0.75 per 1,000). Full pricing is at nyxchain.org/developers/pricing.
Can AI agents call the Nyx Fund API directly?
Yes. A public MCP server at /api/mcp/public speaks the Model Context Protocol over streamable HTTP with no authentication required, exposing the same seven calculators plus a doc-search tool to Claude Code, Claude Desktop, Cursor, ChatGPT, and any spec-compliant JSON-RPC client.
Is the Fund Data API real fund data or a demo?
Both. Every endpoint accepts the published demo key against a synthetic fixture fund for testing, and a real nyx_dk_ key (minted from your Nyx Fund dashboard) returns your own fund's live shadow-NAV data.
Get started
Start with the quickstart
One curl command against the demo key — no signup required.
Read the quickstart →