MCP server

#Connecting

A URL and a header. The server is closed by default: without a valid X-API-KEY, no tool is announced and every request is refused with 401 (X-Deny-Reason: missing_api_key when the header is absent, invalid_api_key when the key is unknown or revoked).

{
  "mcpServers": {
    "bytnode": {
      "type": "http",
      "url": "https://api.bytnode.com/mcp",
      "headers": { "X-API-KEY": "your_key" }
    }
  }
}

The exact shape of the configuration file depends on the agent, but the principle does not change.

#The three tools

All three are read-only, free of side effects and idempotent: an agent can replay them without risk.

await c.call_tool("get_market_indicators", {
    "symbol": "BTCUSDT",
    "timeframe": "1h",
    "limit": 60,
    "indicators": [
        {"id": "rsi_7", "type": "rsi", "period": 7},
        {"id": "rsi_21", "type": "rsi", "period": 21},
        {"id": "macd", "type": "macd", "fast": 12, "slow": 26, "signal": 9},
        {"id": "adx_14", "type": "adx", "period": 14},
    ],
})

#Current value or history

The mode follows from a single thing: the presence of a dated window. Without since_ms or until_ms, get_market_data answers with the current value; with one of them, every requested field answers with its history over the window — several dated metrics in one call.

#Targeting

Each field declares its target: a pair (symbol), an asset (asset), a catalogue series (series) or none, for whole-market data. Anything that does not fit is refused before the first network call, never absorbed, and every problem is listed in the same message.

#The 60 fields

The names are those of the API, the same for the current value and the history, with these differences: the global market is global_market here and global in the REST snapshot (global is a reserved word in Python, and every field is a parameter of the tool); the market is a parameter here (market: "spot") and a path suffix in REST (/v1/cvd/spot); the catalogues are options_expiries and symbol_capabilities (REST: /v1/options/expiry, /v1/capabilities?symbol=…); and a history says the step the tool used in timeframe_applied, since it may choose it. The detail of each field — what it contains, what N counts, its ceiling, its routes — is in its description, which the agent reads in the tool’s schema, and in the data catalogue.

#The response

The data comes back as the API returns it, under one key per field. A field with a timeframe is keyed field@tf. unavailable and out_of_plan_fields are those of the snapshot.

{
  "mode": "latest",
  "data": {
    "klines@1h": [ … ],
    "cvd@1h": [ … ],
    "options_summary": { … },
    "fear_greed": { … }
  },
  "scopes": {
    "symbol:BTCUSDT": ["klines@1h", "cvd@1h"],
    "asset:BTC": ["options_summary"],
    "market": ["fear_greed"]
  },
  "timeframe_applied": "1h",
  "unavailable": { … }
}

• scopes: the real scope of each key — symbol:X, asset:X, series:X or market. A whole-market index asked for alongside a symbol is labelled market, never with the symbol.
• mode: latest or history; in history, window repeats the bounds and ranges gives, per series, what is really covered: step, points, first and last date, and truncated, with how to fetch the rest.
• timeframe_applied: the step actually applied, as soon as a field used it; live: present when the candle still forming was asked for.
• errors and partial: a field in error does not block the others. It is reported under errors and the response carries partial: true.

#Errors

Every error starts with Error (HTTP NNN): message. When the API answered, it ends with [code: …], the API’s stable error.code; a request the server refuses before calling the API (an unknown field, a missing target, a window it cannot serve) has no code. A failed tool call is flagged as an MCP error (isError), never returned as data.