Lightning Wallet MCP

Instructions

Implementation Reference

• src/index.ts:1251-1267 (handler)

  MCP tool handler for "set_budget" in index.ts.

  case 'set_budget': {
    const parsed = SetBudgetSchema.parse(args);
    const result = await session.requireClient().setBudget(parsed.agent_id, parsed.budget_limit_sats);
    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify({
            success: true,
            message: `Budget updated to ${parsed.budget_limit_sats} sats`,
            agent_id: result.agentId,
            new_budget_limit_sats: result.newBudgetLimitSats,
          }, null, 2),
        },
      ],
    };
  }

• src/lightning-faucet.ts:721-739 (handler)

  Implementation of the setBudget method in the LightningFaucetClient class.

  async setBudget(agentId: number, budgetLimitSats: number): Promise<{
    agentId: number;
    newBudgetLimitSats: number;
    rawResponse: ApiResponse;
  }> {
    const result = await this.request<ApiResponse & {
      agent_id?: number;
      budget_limit_sats?: number;
    }>('update_agent', {
      agent_id: agentId,
      updates: { budget_limit_sats: budgetLimitSats === 0 ? null : budgetLimitSats },
    });
  
    return {
      agentId: result.agent_id || agentId,
      newBudgetLimitSats: budgetLimitSats,
      rawResponse: result,
    };
  }

• src/index.ts:183-186 (schema)

  Zod schema definition for the set_budget tool.

  const SetBudgetSchema = z.object({
    agent_id: z.number().int().positive().describe('Agent ID to update'),
    budget_limit_sats: z.number().int().min(0).describe('New budget limit in sats (0 for unlimited)'),
  });

• src/index.ts:545-555 (registration)

  Tool registration in the ListToolsRequestSchema handler.

    name: 'set_budget',
    description: 'Set or update budget limit for an agent. REQUIRES OPERATOR KEY.',
    inputSchema: {
      type: 'object',
      properties: {
        agent_id: { type: 'integer', description: 'Agent ID to update' },
        budget_limit_sats: { type: 'integer', minimum: 0, description: 'New budget limit in sats (0 for unlimited)' },
      },
      required: ['agent_id', 'budget_limit_sats'],
    },
  },