---
title: "MCP server: JSON-RPC 2.0 over streamable HTTP (keyless and free-plan calls not billed; paid-plan calls metered)"
method: POST
path: "/mcp"
tags: ["free"]
---

# MCP server: JSON-RPC 2.0 over streamable HTTP (keyless and free-plan calls not billed; paid-plan calls metered)

`POST /mcp`

## Request

- Base URL: `https://coinlobster.com`
- URL: `https://coinlobster.com/mcp`
- Auth: none required

The Model Context Protocol server over streamable HTTP. Stateless: every POST is a fresh session. Two URLs, same tools: https://coinlobster.com/mcp/connector signs the user in over OAuth (a free account is live), https://coinlobster.com/mcp is keyless (answers 30 minutes old). Registers 21 tools: coin_brief, market_now, whale_activity, whale_radar, market_screener, liquidations, traders, wallet, signals, situations, history, options, orderbook, news, sectors, big_catch, watch, my_alerts, watchlist_brief, my_access, coin_search. 41 older tool names still answer, each routed to the tool above that now owns it. whale_tape is a deprecated alias of whale_activity, still callable. All read-only except watch, which arms and removes alerts posted to the caller's webhook (Starter and up). my_access reports what the calling connection can see, the caps in force on it and what lifts each one; it is free and never spends credits. Keyless and free-plan calls are never billed: 100 calls a day without an account, 200 calls a day with a free account. The free plans answer BTC in full and any other coin as a headline with its price, 24h change and news, over the last 24 hours. A paid plan (Starter $15, Pro $29, Alpha $99 a month), as an OAuth-connected account or a cl_ key in X-API-Key, answers every coin in full; each successful tools/call then spends 20 to 100 credits, priced by workload, from the balance the website and REST API share. Discovery (initialize, tools/list, ping), failed calls and no-data answers cost nothing. Descriptive market data only, no forecast language.

## Headers

- `X-API-Key` string

## Request body

- object

## Response `200`

JSON-RPC 2.0 response (or an SSE stream, per Accept header)

- object
  - `success` true, required
  - `data` object, required: Endpoint-specific payload. Every field it carries is documented in llms-full.txt and returned by /discover.
  - `meta` Meta: Present on every /api/ai/v1 response.
    - `timestamp` string, date-time: When this response was assembled, not when the data was measured.
    - `credits_used` integer: Credits this call spent. Absent on free surfaces and on keyless calls.
    - `credits_remaining` integer: Account balance after this call.
    - `deprecation` string: Present when the request used a deprecated form, e.g. the key in the query string.

## Other responses

- `403`: Origin not allowed
- `429`: Rate limit reached (Retry-After header set)

---

[API](https://skmtc.dev/coinlobster/apis/coinlobster-crypto-data-api.md) · [All operations](https://skmtc.dev/coinlobster/apis/coinlobster-crypto-data-api/llms.txt) · [OpenAPI document](https://skmtc.dev/coinlobster/apis/coinlobster-crypto-data-api/revisions/a62c3a47523a?raw)