lightningprox-mcp

Instructions

Implementation Reference

• src/index.ts:196-212 (handler)

  The handler logic for the 'chat' tool inside the MCP server request handler.

  case "chat": {
    const { model, message, spend_token, max_tokens } = args as any;
    const result = await chat(model, message, spend_token, max_tokens);
  
    const content =
      result.content?.[0]?.text ||
      result.choices?.[0]?.message?.content ||
      JSON.stringify(result);
  
    const usage = result.usage
      ? `\n\n— ${result.usage.input_tokens ?? result.usage.prompt_tokens ?? "?"} in / ${result.usage.output_tokens ?? result.usage.completion_tokens ?? "?"} out`
      : "";
  
    return {
      content: [{ type: "text", text: content + usage }],
    };
  }

• src/index.ts:112-135 (helper)

  The helper function that performs the network request to the AI model API.

  async function chat(
    model: string,
    message: string,
    spendToken: string,
    maxTokens: number = 1024
  ): Promise<any> {
    const res = await fetch(`${LIGHTNINGPROX_URL}/v1/messages`, {
      method: "POST",
      headers: {
        "Content-Type": "application/json",
        "X-Spend-Token": spendToken,
      },
      body: JSON.stringify({
        model,
        messages: [{ role: "user", content: message }],
        max_tokens: maxTokens,
      }),
    });
    if (!res.ok) {
      const err = await res.json() as any;
      throw new Error(err.error || `LightningProx error: ${res.status}`);
    }
    return res.json();
  }

• src/index.ts:23-50 (schema)

  Tool definition and schema for the 'chat' tool.

  {
    name: "chat",
    description:
      "Send a message to an AI model via LightningProx. Pay per request with a Lightning spend token. Supports 19 models from Anthropic, OpenAI, Together.ai, Mistral, and Google.",
    inputSchema: {
      type: "object",
      properties: {
        model: {
          type: "string",
          description:
            "Model ID (e.g. claude-opus-4-5-20251101, gpt-4-turbo, gemini-2.5-pro, mistral-large-latest, deepseek-ai/DeepSeek-V3)",
        },
        message: {
          type: "string",
          description: "The user message to send",
        },
        spend_token: {
          type: "string",
          description: "LightningProx spend token (starts with lnpx_). Get one at lightningprox.com/topup",
        },
        max_tokens: {
          type: "number",
          description: "Maximum tokens in response (default: 1024)",
        },
      },
      required: ["model", "message", "spend_token"],
    },
  },