MCP tools are native tool calls. The agent does not write HTTP client code — the LLM client calls the tool directly, the same way it would call any other function. Purple Flea ships three MCP servers that give AI agents a complete financial toolkit: free starting funds, trustless payments, and a casino.
Why MCP Matters for Financially Capable Agents
The Model Context Protocol (MCP) is the emerging standard for giving AI agents direct access to external capabilities. When a server exposes an MCP endpoint, any compatible client — Claude Desktop, Cursor, Windsurf, a custom agent built on the Anthropic SDK — can discover its tools and call them exactly as if those tools were built into the model itself.
This distinction is critical. Before MCP, developers wrote API wrapper code: fetch, authenticate, parse, handle errors, retry. That scaffolding runs outside the model. The model reasons about what to do; the developer's code handles doing it. MCP collapses this separation. The model calls faucet_claim the same way it calls read_file. There is no glue code. There is no client library to install.
For financial operations, this is genuinely transformative. An agent that needs to claim startup funds, lock payment in escrow, and check a casino balance can do all three inside a single chain of thought, using nothing but tool calls — without the developer having written a single line of HTTP client code.
What is StreamableHTTP? All Purple Flea MCP servers use the StreamableHTTP transport, the current MCP spec standard. Unlike the older SSE transport, StreamableHTTP supports proper bidirectional communication and lower latency. Most MCP clients support it with a simple "transport": "streamable-http" field.
Purple Flea's Three MCP Servers
Purple Flea operates three live MCP endpoints. Each is a StreamableHTTP server, reachable directly over HTTPS, with no installation required on the client side.
Agent Faucet
Dispenses $1 USDC to newly registered agents. No authentication required to check stats; a unique agent_id is required to claim. Each identity can claim once. The faucet is the entry point for agents that have no existing funds — it removes the cold-start problem entirely.
Agent Escrow
Trustless agent-to-agent payments via on-chain escrow contracts. One agent locks funds with a condition; another agent fulfills the condition; the escrow releases automatically. Fee: 1% of the escrowed amount. Referral commission: 15% of fees earned. Requires a Bearer API key for escrow_create and escrow_release.
Casino
Provably fair gambling for agents. Supports coin flip, dice roll, and crash — each game is verifiably random using on-chain entropy. The casino is also the primary way agents deploy faucet funds: the intended flow is claim → play → compound. A balance tool lets trading agents include casino positions in portfolio overviews.
Tool Reference: What Each Tool Does
| Tool | Auth Required | Purpose |
|---|---|---|
| faucet_stats | None | Returns total claims, available balance, and claim amount |
| faucet_claim | agent_id | Registers a new agent and transfers $1 USDC to its wallet |
| escrow_stats | None | Returns active escrow count, total locked value, and fee rate |
| escrow_create | Bearer key | Locks funds in escrow with a payee address and release condition |
| escrow_release | Bearer key | Releases escrowed funds to payee upon condition fulfillment |
| casino_balance | Bearer key | Returns wallet balance and current game history for the agent |
| casino_flip | Bearer key | Places a coin-flip bet (heads/tails, 1x payout) |
| casino_dice | Bearer key | Rolls a provably fair die; over/under betting supported |
| casino_crash | Bearer key | Places a crash-game bet with a configurable cash-out multiplier |
Setting Up in Claude Desktop
Claude Desktop reads MCP server configuration from ~/Library/Application Support/Claude/claude_desktop_config.json on macOS (or the equivalent AppData path on Windows). Add the Purple Flea servers to the mcpServers object:
{
"mcpServers": {
"purple-flea-faucet": {
"url": "https://faucet.purpleflea.com/mcp",
"transport": "streamable-http"
},
"purple-flea-escrow": {
"url": "https://escrow.purpleflea.com/mcp",
"transport": "streamable-http",
"headers": {
"Authorization": "Bearer sk_live_YOUR_KEY"
}
},
"purple-flea-casino": {
"url": "https://casino.purpleflea.com/mcp",
"transport": "streamable-http",
"headers": {
"Authorization": "Bearer sk_live_YOUR_KEY"
}
}
}
}
After saving the file and restarting Claude Desktop, the tools appear in the tool picker. You can then ask Claude to check the faucet balance, claim funds for a new agent, or create an escrow — and it will call the tools directly, with no additional code on your part.
No API key needed for stats. The faucet_stats and escrow_stats tools are unauthenticated. You can add the faucet server without any headers and immediately ask Claude for live faucet statistics without signing up for anything.
Setting Up in Cursor
Cursor uses the same MCP JSON format, stored at .cursor/mcp.json in your project root (project-scoped) or ~/.cursor/mcp.json (global). The config schema is identical to Claude Desktop:
{
"mcpServers": {
"purple-flea-faucet": {
"url": "https://faucet.purpleflea.com/mcp",
"transport": "streamable-http"
},
"purple-flea-escrow": {
"url": "https://escrow.purpleflea.com/mcp",
"transport": "streamable-http",
"headers": {
"Authorization": "Bearer sk_live_YOUR_KEY"
}
}
}
}
Reload Cursor's MCP configuration from the settings panel (MCP tab) after saving. Cursor's Composer and Agent modes will pick up the new tools on the next session. You can verify connectivity by asking the agent to call faucet_stats — it should return live data without any additional configuration.
Why StreamableHTTP Over SSE
The original MCP transport was Server-Sent Events (SSE). SSE works but carries meaningful limitations: it is a one-way push channel, server to client, with a separate HTTP POST channel back the other way. This means two connections, more complex session management, and architectural friction when the client is behind a proxy or load balancer.
StreamableHTTP replaces this with a single, properly bidirectional HTTP stream. The client opens one connection; messages flow in both directions over that connection. The result is lower latency, simpler infrastructure, and correct behavior in environments where long-lived SSE connections are unreliable — including serverless runtimes and most corporate proxies.
All three Purple Flea MCP servers are StreamableHTTP-only. There is no SSE fallback. This is a deliberate choice: maintaining dual transport support introduces complexity that benefits a shrinking minority of clients as the ecosystem has moved rapidly toward StreamableHTTP as the default.
Real Use Cases
Agent-to-Agent Task Markets
Consider an orchestrator agent that hires specialist agents to complete subtasks: one for data retrieval, one for analysis, one for report generation. Each specialist expects payment on completion. The orchestrator calls escrow_create to lock funds for each specialist before the task begins. Each specialist knows the funds are locked and will release automatically when they submit valid work. Neither side needs to trust the other — the escrow enforces the agreement. The 1% fee is the price of that trustlessness.
New Agent Cold Start via Faucet
A freshly spawned agent has a wallet but no funds. Its first tool call is faucet_claim with its unique identity. The faucet transfers $1 USDC. The agent now has enough to run a few casino games, test its strategy, and decide whether to deposit more real funds before scaling up. The faucet is not charity — it is the onboarding ramp for the casino's customer acquisition funnel. The agent gets zero-risk entry; Purple Flea gets an activated user.
Portfolio Monitoring Across Services
A trading agent that monitors multiple positions can call casino_balance as part of a scheduled portfolio sweep — alongside exchange balances, DeFi positions, and wallet holdings. The casino position is just another asset in the portfolio. The agent does not need to know it is calling an MCP server; from its perspective, it is calling a tool named casino_balance that returns a number.
Referral income for MCP integrations. If your agent or platform refers other agents to Purple Flea's escrow service, you earn 15% of all fees generated by referred agents — paid automatically, on-chain. Configure your referral code in the escrow server's header config.
Related Tools and Resources
If you want to generate a complete MCP config without writing JSON by hand, use the MCP Config Generator at /mcp-config-generator. Select the servers you need, enter your API key, and it outputs the correct JSON for Claude Desktop, Cursor, or any other MCP client.
All three servers are also listed on the Smithery marketplace at smithery.ai/servers/purpleflea/faucet and smithery.ai/servers/purpleflea/escrow. The Smithery listing provides one-click installation for supported clients and a live tool explorer where you can inspect the tool schemas before connecting.
Wire Up the Tools in 60 Seconds
Add the faucet server to Claude Desktop now — no API key, no signup. Ask Claude to call faucet_stats and see live data from the Purple Flea faucet.