BananaCrystal: FX rates, swaps and payments in 140+ currencies

Name: BananaCrystal: FX rates, swaps and payments in 140+ currencies
Author: BananaCrystal

by BananaCrystalversion 1.1.0i★ –iRuns in the cloud

Registry namecom.bananacrystal/mcp

Install

Overview

Description from the maker (original English)

Give your AI agent a wallet: live FX rates, swaps and payments in 140+ local currencies.

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

User voiceiNo reviews yetReviews open together with accounts in a later step
Our basic checksi3 of 3 passedChecked from public information; code not scanned yet
UsageiNot measured yet★ –

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

Connection: Runs in the cloud
Transport: Streamable HTTP
Category: Other
You need to fill in: x-api-key

Install

Pick the AI app you use, then copy the settings.

Before you install

Basic checks: 3 of 3 passed
Runs on the maker’s server: what you ask it goes through their server.
You fill in yourself: x-api-key

Values marked secret are keys to your account. Never share them or paste them into a chat.

You need

Runs in the cloudNothing to install; it connects over the internet

Which app do you use?

ClaudeClaude CodeCursorVS CodeChatGPT

Pick your app above. We remember it, so next time the button says “Install in …”.

This address needs a key in a request header, which the add-connector menu cannot set. Use Claude Code, Cursor or VS Code instead.

Run this in your terminal

claude mcp add --transport http bananacrystal https://agentic.bananacrystal.com/mcp --header 'x-api-key: your-value'

Fill in the empty values before running it.

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "bananacrystal": {
      "url": "https://agentic.bananacrystal.com/mcp",
      "headers": {
        "x-api-key": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "bananacrystal": {
      "type": "http",
      "url": "https://agentic.bananacrystal.com/mcp",
      "headers": {
        "x-api-key": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This address needs a key in a request header, which the add-connector menu cannot set. Use Claude Code, Cursor or VS Code instead.

Your choice stays on this device in a cookie; no account needed.

Values you fill in

x-api-key secret HTTP header
API key from agents.bananacrystal.com/account. Sandbox keys start with bc_test_. Leave empty to sign in with OAuth instead.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

The server asks you to sign in before it lists its tools.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 8, 2026

✓ Pass
Maker matches the repo
The registry name was verified against the domain bananacrystal.com (the registry checks domain ownership)
… Not checked yet
Still maintained
We have not read this repo from GitHub yet
… Not checked yet
Has a licence
We have not read this repo from GitHub yet
✓ Pass
Endpoint responds
Responded in 102 ms (HTTP 401)
✓ Pass
Sign-in with OAuth
Declares OAuth sign-in, so your AI app can take you to log in
… Not checked yet
No hidden instructions in tool descriptions
Not checked yet; we read the tool list when we check the endpoint

Compared with others in Otheri

More stars than 0% of the other 18437 servers in this category
Published to the registry more recently than 97% of the other 18437 servers in this category
Basic checks equal to or better than 100% of the other 18437 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is BananaCrystal: FX rates, swaps and payments in 140+ currencies safe?

It passed 3 of 3 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

You need to fill in: x-api-key

Does it run on my computer or in the cloud?

It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.1.0) reached the registry yesterday.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.

What can I use instead?

In the same category: Spec Driven Development, Remote Desktop Commander, ProAgentStore

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Spec Driven Development

by formulahendry

MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.

Runs on your computer★ 440MITUpdated 14 months ago

Install

Remote Desktop Commander

by desktop-commander

Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.

Runs in the cloud★ 211Updated 3 days ago

Install

ProAgentStore

by ProAgentStore

MCP-first control plane for ProAgentStore agents and private instances.

Runs in the cloudUpdated today

Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

BananaCrystal MCP Server

Give your AI agent a wallet: live FX rates, swaps and payments in 140+ local currencies.

One hosted MCP endpoint. 40 tools. Free sandbox. Settles on Hedera in under 5 seconds.

https://agentic.bananacrystal.com/mcp

Docs · Get a free sandbox key · API reference · Security policy

What this is

BananaCrystal is a hosted MCP server that gives an AI agent a wallet it can actually spend from. The agent can check balances, get a live exchange rate, swap between 140+ local-currency stablecoins, send money to another user, and move funds in and out of fiat, all through standard MCP tool calls. Limits are enforced on our side, so the agent never holds a private key and can never spend past the cap you set.

This repository holds the configuration files for connecting an MCP client to the hosted server. There is nothing to install or run locally. The server itself is hosted and maintained by BananaCrystal.

Connect in five minutes

Create a free account at agents.bananacrystal.com/account and copy a sandbox key. Sandbox keys start with bc_test_ and come with test balances, so nothing real moves.
Add the server to your MCP client.
Ask your agent: *"What is my USDb balance?"*

Claude Desktop, Claude Code, Cursor, Windsurf, VS Code

Add this to your client's MCP config (claude_desktop_config.json, ~/.cursor/mcp.json, .vscode/mcp.json, or the equivalent):

"mcpServers": { "bananacrystal": { "url": "https://agentic.bananacrystal.com/mcp", "headers": { "x-api-key": "bc_test_your_key" } } } }

Clients that do not yet accept a url entry directly (older Claude Desktop builds) can use mcp-remote:

"mcpServers": { "bananacrystal": { "command": "npx", "args": [ "-y", "mcp-remote", "https://agentic.bananacrystal.com/mcp", "--header", "x-api-key:${BANANACRYSTAL_API_KEY}" ], "env": { "BANANACRYSTAL_API_KEY": "bc_test_your_key" } } } }

Claude Code (one line)

claude mcp add --transport http bananacrystal https://agentic.bananacrystal.com/mcp --header "x-api-key: bc_test_your_key"

Gemini CLI

gemini extensions install https://github.com/BananaCrystal/mcp-server-bananacrystal

export BANANACRYSTAL_API_KEY=bc_test_your_key

ChatGPT, Claude.ai connectors, and OAuth clients

Add https://agentic.bananacrystal.com/mcp as a custom connector or remote MCP server. Leave the API key empty and the client will walk you through OAuth 2.0 sign-in. The server advertises its authorization server at /.well-known/oauth-protected-resource.

Any language, no SDK

The server speaks Streamable HTTP, so any MCP client library works. The only thing you need is the URL and a key.

curl -s https://agentic.bananacrystal.com/mcp \

-H "content-type: application/json" \ -H "x-api-key: bc_test_your_key" \ -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

What your agent can do

Group	Tools	Fee
Read-only	`get_balances`, `get_exchange_rate`, `get_transaction_history`, `get_my_limits`, `estimate_swap_fees` and 19 more	Free
Transfer	`request_transfer_otp`, `transfer_tokens`	0.3%
Swap	`swap_currency` across 140+ local-currency stablecoins	0.5%
Fiat	`initiate_kyc`, `initiate_deposit`, `request_withdrawal`	Partner rate shown before you confirm
Offers and trades	`create_offer`, `update_offer`, `engage_offer`, `cancel_trade` and 2 more	Free to list
Agent to agent	`request_agent_transaction`, `execute_approved_transaction` and 1 more	0.3%

The full list with input schemas is at agents.bananacrystal.com/docs/mcp. Every tool also returns its schema through tools/list.

Example: pay an invoice in rupiah

User:  Pay Putri's invoice: Rp 1,500,000 from my USD balance.

Agent: get_exchange_rate(USD, IDR) -> 1 USD = 16,360 IDR swap_currency(91.69 USDb -> IDRb) -> 1,500,000 IDRb, fee 0.5% request_transfer_otp() -> code sent to your email [you enter the 6-digit code] transfer_tokens(1,500,000 IDRb, @putri) -> settled in 3.4s

Paid. Total cost $0.73. Receipt saved.

Guardrails

Everything that limits spending lives on the server, not in the agent's prompt.

Scoped API keys. Each key gets only the scopes it needs: read, transfer, swap, fiat. A read-only key cannot move money, whatever the prompt says.
Per-transaction maximum and rolling 24-hour cap, set per key in your account and enforced server-side. A runaway loop stops at the number you chose.
Email one-time code on transfers, swaps and withdrawals, on by default. The agent can request the code; only you can supply it.
Idempotent requests. Retrying a call never pays twice.
Sandbox is a separate environment. bc_test_ keys never touch real balances.

Pricing

Reads are free. Transfers cost 0.3% and swaps 0.5%, charged in the currency you send. There is no monthly fee, no minimum and no per-call charge. Fiat deposits and withdrawals carry the partner's rate, which the agent sees before it confirms.

Sandbox and production

	Sandbox	Production
Key format	`bc_test_` prefix	64 hex characters, no prefix
Balances	Test funds, reset on request	Real
KYC	Not required	Required before fiat tools
Rate limit	Returned by `get_my_limits`	Returned by `get_my_limits`

About BananaCrystal

BananaCrystal is a registered money services business in the United States (FinCEN) and Canada (FINTRAC). Stablecoins are issued on Hedera and each local-currency token is backed one to one by the deposits that minted it. Learn more at bananacrystal.com.

Support and security

Questions and integration help: support@bananacrystal.com
Security reports: security@bananacrystal.com. Please read SECURITY.md before reporting.
Privacy policy: bananacrystal.com/privacy

License

The configuration files in this repository are released under the MIT License. Use of the hosted server is governed by the BananaCrystal Terms and Conditions.

BananaCrystal: FX rates, swaps and payments in 140+ currencies

Overview

PopNx MCP’s three pillars

What you can do with it

Install

Before you install

Values you fill in

What it can do

Basic checksi

Maker matches the repo

Still maintained

Has a licence

Endpoint responds

Sign-in with OAuth

No hidden instructions in tool descriptions

Compared with others in Otheri

Common questions

Alternatives

Spec Driven Development

Remote Desktop Commander

ProAgentStore

README from the maker

BananaCrystal MCP Server

What this is

Connect in five minutes

Claude Desktop, Claude Code, Cursor, Windsurf, VS Code

Claude Code (one line)

Gemini CLI

ChatGPT, Claude.ai connectors, and OAuth clients

Any language, no SDK

What your agent can do

Example: pay an invoice in rupiah

Guardrails

Pricing

Sandbox and production

About BananaCrystal

Support and security

License