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                                                                    Exhibit 99.2

                             FIRST AMENDMENT DATED
                             AS OF AUGUST 30, 1999
                         TO LOAN DOCUMENTS AND GUARANTY

     THIS AMENDMENT, dated as of August 30, 1999, is entered into among ONEPOINT
COMMUNICATIONS CORP., a Delaware corporation (the "Borrower"), SBC
COMMUNICATIONS INC., a Delaware corporation (the "Guarantor"), and THE NORTHERN
TRUST COMPANY, an Illinois banking corporation having an office at 265 East
Deerpath Road, Lake Forest, Illinois 60045 (the "Lender").


                                   RECITALS:

     A.  The Borrower has previously delivered to the Lender (i) an Amended and
Restated Call On Term - Term Note dated as of April 29, 1998 in the original
principal amount of $9,000,000 (as amended, modified, restated or replaced, the
"Note") and (ii) an Amended and Restated Security Agreement dated as of April
29, 1998 (as amended, modified, restated or replaced, the "Security Agreement";
together with the Note, collectively the "Loan Documents" and individually, a
"Loan Document").

     B.  Guarantor has previously delivered to the Lender an Amended and
Restated Guaranty dated as of April 29, 1998 (as amended, modified or replaced,
the "Guaranty"). Terms defined in the Loan Documents or the Guaranty and not
otherwise defined herein shall be used herein as defined in the Loan Documents
and the Guaranty, as applicable.

     C.  The Borrower, the Guarantor and the Lender wish to amend the Loan
Documents and the Guaranty.

     D.  Therefore, the parties hereto agree as follows:

         1.  AMENDMENTS TO THE NOTE.

             1.1.  Section 2.2 of the Note.  Section 2.2 of the Note is hereby
         amended as of the date hereof by deleting the first sentence thereof
         and substituting the following therefor:

             "2.2  MANDATORY PREPAYMENT.  In the event that twenty percent (20%)
         or more of the issued and outstanding shares of the Borrower are held
         by persons not owning shares of the Borrower, directly or indirectly,
         on April 29, 1998 or substantially all the assets of the Borrower are
         sold, then on the date such event shall occur, the Borrower immediately
         agrees to prepay the entire outstanding principal amount of the Loans
         and all unpaid and accrued interest on the Loans and acknowledges and
         agrees that any commitment to lend hereunder is terminated without
         further notice or action on the part of the Lender."
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     1.2. Section 5 of the Note. The definition of "Subsidiary" in Section 5 of
the Note is hereby amended as of the date hereof by deleting the percentage
"eighty percent (80%)" appearing therein and substituting the percentage "fifty
percent (50%)" therefor.

     1.3. Sections 6(c), (d), (f), (g), (h), (i), (l) and (m) of the Note.
Sections 6(c), (d), (f), (g), (h), (i), (l) and (m) only of the Note are hereby
amended and restated in their entirety as of the date hereof as follows:

          "(c) failure of Borrower or any of its Subsidiaries or the Guarantor
     to pay when due any principal of or interest on or any other amount payable
     in respect of one or more items of indebtedness or reimbursement obligation
     in an aggregate amount in excess of $5,000,000 ($100,000,000 in the case of
     the Guarantor only), in each case beyond the end of any grace period
     provided therefor, or any breach or default by Borrower or any of its
     Subsidiaries or the Guarantor with respect to any term of one or more terms
     of indebtedness or reimbursement obligation in the aggregate principal
     amount in excess of $5,000,000 ($100,000,000 in the case of the Guarantor
     only) shall occur if the effect of such breach or default is to cause, or
     permit the holders of that indebtedness to cause, that indebtedness to
     become due and payable prior to its stated maturity;

          (d) any representation, warranty, schedule, certificate, financial
     statement, report, notice, or other writing furnished by or on behalf of
     Borrower, any Subsidiary or Guarantor to Lender is false or misleading in
     any material respect on the date as of which the facts therein set forth
     are stated or certified; . . .

          (f) Borrower, any Subsidiary or Guarantor shall fail to maintain their
     existence in good standing in their state of formation or shall fail to be
     duly qualified, in good standing and authorized to do business in each
     jurisdiction where failure to do so is reasonably likely to have a material
     adverse impact on the consolidated assets, condition or prospects of
     Borrower and such failure is not cured within ten (10) days of the
     Borrower, such Subsidiary or the Guarantor having actual notice that they
     are not in good standing or duly qualified;

          (g) Borrower, any Subsidiary or Guarantor shall dissolve, liquidate,
     merge, consolidate, or cease to be in existence for any reason; provided
     that, the Borrower or any Subsidiary may merge or consolidate with
     Guarantor or any one or more Subsidiaries of Borrower or with any other
     entity if, before and after giving effect thereto, no Event of Default
     shall have occurred and be continuing and the surviving entity assumes all
     the obligations and duties of the Borrower under this Note and the
     obligations of the Borrower continue to be guaranteed by a creditworthy
     entity and in form and substance satisfactory to the Lender; provided
     further that this clause (g) shall not apply to any Subsidiary to be
     liquidated or dissolved if the Board of Directors of such Subsidiary shall
     determine that the preservation of the existence of such Subsidiary is no
     longer

                                      -2-
<PAGE>

     desirable in the conduct of business of the Borrower and its Subsidiaries,
     and that the loss thereof is not disadvantageous in any material respect to
     Lender, as reasonably determined by the Lender;

          (h) James A. Otterbeck and the Guarantor in the aggregate shall cease
     to own, directly or indirectly, at least 51% of the issued and outstanding
     common stock of Borrower entitled to vote for the election of directors of
     Borrower;

          (i) any proceeding (judicial or administrative) shall be commenced
     against Borrower, any Subsidiary or the Guarantor, or with respect to any
     assets of Borrower, any Subsidiary or the Guarantor which could reasonably
     be expected to have a material and adverse effect on the assets, condition
     or prospects of Borrower, any Subsidiary or the Guarantor; or final
     judgment(s) and/or settlement(s) in an aggregate amount in excess of (i) in
     the case of the Guarantor, TWENTY-FIVE MILLION AND NO/100 UNITED STATES
     DOLLARS ($25,000,000.00), or (ii) in the case of the Borrower or any
     Subsidiary, ONE MILLION AND NO/100 UNITED STATES DOLLARS ($1,000,000), in
     each case in excess of insurance for which the insurer has confirmed
     coverage in writing, a copy of which writing has been furnished to Lender,
     shall be entered or agreed to in any suit or action; . . .

          (l) any bankruptcy, insolvency, reorganization, arrangement,
     readjustment, liquidation, dissolution, or similar proceeding, domestic or
     foreign, is instituted by or against Borrower, any Subsidiary or the
     Guarantor and in the case of an involuntary proceeding is not dismissed
     within 60 days; or Borrower, any Subsidiary or the Guarantor shall take any
     steps toward, or to authorize, such a proceeding; or

          (m) Borrower, any Subsidiary or any Guarantor shall become insolvent,
     generally shall fail or be unable to pay its debts as they mature, shall
     admit in writing its inability to pay its debts as they mature, shall make
     a general assignment for the benefit of its creditors, shall enter into any
     composition or similar agreement, or shall suspend the transaction of all
     or a substantial portion of its usual business."

     1.4. Section 6(e) of the Note. Section 6(e) of the Note is hereby amended
as of the date hereof by adding the following immediately after the semicolon
but before the word "or" appearing therein:

     "or the senior unsecured debt rating of Guarantor shall be less than BBB by
     Standard & Poor's, a division of McGraw Hill Company, Inc. or Baa by
     Moody's Investors Services, Inc.;"

     1.5. Section 6(j) of the Note. Section 6(j) of the Note is hereby amended
as of the date hereof by deleting everything after the word "documents;"
appearing therein and substituting the following therefor:

                                      -3-
<PAGE>

     "or any notice of a federal tax lien against Borrower in excess of
     $1,000,000 shall be filed with any public recorder and such lien is not
     vacated, discharged, stayed or bonded over for a period of 60 days; or"

     2.  AMENDMENTS TO THE SECURITY AGREEMENT.

     2.1.  Section 1(d) of the Security Agreement.  Section 1(d) of the Security
Agreement is hereby amended as of the date hereof by deleting the percentage
"80%" appearing therein and substituting the percentage "50%" therefor.

    2.2.  Sections 9(c), (d), (f), (g), (h), (i), (j) (l) and (m) of the
Security Agreement. Sections 9(c), (d), (f), (g), (h), (i), (j), (l) and (m)
only of the Security Agreement are hereby amended and restated in their entirety
as of the date hereof as follows:

          "(c) failure of Debtor or any of its Subsidiaries or the Guarantor to
     pay when due any principal of or interest on or any other amount payable in
     respect of one or more items of indebtedness or reimbursement obligation in
     an aggregate amount in excess of $5,000,000 ($100,000,000 in the case of
     the Guarantor only), in each case beyond the end of any grace period
     provided therefor, or any breach or default by Debtor or any of its
     Subsidiaries or the Guarantor with respect to any term of one or more terms
     of indebtedness or reimbursement obligation in the aggregate principal
     amount in excess of $5,000,000 ($100,000,000 in the case of the Guarantor
     only) shall occur if the effect of such breach or default is to cause, or
     permit the holders of that indebtedness to cause, that indebtedness to
     become due and payable prior to its stated maturity;

          (d) any representation, warranty, schedule, certificate, financial
     statement, report, notice, or other writing furnished by or on behalf of
     Debtor, any Subsidiary or Guarantor to Secured Party is false or misleading
     in any material respect on the date as of which the facts therein set forth
     are stated or certified; . . .

          (f) Debtor, any Subsidiary or Guarantor shall fail to maintain their
     existence in good standing in their state of formation or shall fail to be
     duly qualified, in good standing and authorized to do business in each
     jurisdiction where failure to do so is reasonably likely to have a material
     adverse impact on the consolidated assets, condition or prospects of Debtor
     and such failure is not cured within ten (10) days of the Debtor, such
     Subsidiary or the Guarantor having actual notice that they are not in good
     standing or duly qualified;

          (g) Debtor, any Subsidiary or Guarantor shall dissolve, liquidate,
     merge, consolidate, or cease to be in existence for any reason; provided
     that, the Debtor or any Subsidiary may merge or consolidate with Guarantor
     or any one or more Subsidiaries of Debtor or with any other entity if,
     before and after giving effect thereto, no Event of Default shall have
     occurred and be continuing and the surviving entity assumes all the
     obligations and duties of the Debtor under this Note and the obligations of
     the Debtor continue to be guaranteed by a

                                      -4-
<PAGE>

     creditworthy entity and in form and substance satisfactory to the Secured
     Party; provided further that this clause (g) shall not apply to any
     Subsidiary to be liquidated or dissolved if the Board of Directors of such
     Subsidiary shall determine that the preservation of the existence of such
     Subsidiary is no longer desirable in the conduct of business of the Debtor
     and its Subsidiaries, and that the loss thereof is not disadvantageous in
     any material respect to Secured Party, as reasonably determined by the
     Secured Party;

          (h) James A. Otterbeck and the Guarantor in the aggregate shall cease
     to own, directly or indirectly, at least 51% of the issued and outstanding
     common stock of Debtor entitled to vote for the election of directors of
     Debtor;

          (i) any proceeding (judicial or administrative) shall be commenced
     against Debtor, any Subsidiary or the Guarantor, or with respect to any
     assets of Debtor, any Subsidiary or the Guarantor which could reasonably be
     expected to have a material and adverse effect on the assets, condition or
     prospects of Debtor, any Subsidiary or the Guarantor; or final judgment(s)
     and/or settlement(s) in an aggregate amount in excess of (i) in the case of
     the Guarantor, TWENTY-FIVE MILLION AND NO/100 UNITED STATES DOLLARS
     ($25,000,000.00), or (ii) in the case of the Debtor or any Subsidiary, ONE
     MILLION AND NO/100 UNITED STATES DOLLARS ($1,000,000), in each case in
     excess of insurance for which the insurer has confirmed coverage in
     writing, a copy of which writing has been furnished to Secured Party, shall
     be entered or agreed to in any suit or action; . . .

          (l) any bankruptcy, insolvency, reorganization, arrangement,
     readjustment, liquidation, dissolution, or similar proceeding, domestic or
     foreign, is instituted by or against Debtor, any Subsidiary or the
     Guarantor and in the case of an involuntary proceeding is not dismissed
     within 60 days; or Debtor, any Subsidiary or the Guarantor shall take any
     steps toward, or to authorize, such a proceeding; or

          (m) Debtor, any Subsidiary or any Guarantor shall become insolvent,
     generally shall fail or be unable to pay its debts as they mature, shall
     admit in writing its inability to pay its debts as they mature, shall make
     a general assignment for the benefit of its creditors, shall enter into any
     composition or similar agreement, or shall suspend the transaction of all
     or a substantial portion of its usual business."

     2.3.  Section 9(e) of the Security Agreement.  Section 9(e) of the Security
Agreement is hereby amended as of the date hereof by adding the following
immediately after the semicolon but before the "or" appearing therein:

     "or the senior unsecured debt rating of Guarantor shall be less than BBB by
     Standard & Poor's, a division of McGraw Hill Company, Inc. or Baa by
     Moody's Investors Services, Inc.;"

                                      -5-
<PAGE>

     2.4.  Section 9(j) of the Security Agreement.  Section 9(j) of the Security
Agreement is hereby amended as of the date hereof by deleting everything after
the phrase "with the terms hereof" appearing therein and substituting the
following therefor:

     "or any notice of a federal tax lien against Debtor in excess of $1,000,000
     shall be filed with any public recorder and such lien is not vacated,
     discharged, stayed or bonded over for a period of 60 days; or"

     3.  AMENDMENTS TO THE GUARANTY

     3.1.  Section 2 of the Guaranty.  Section 2 of the Guaranty is hereby
amended as of the date hereof by (i) adding a new clause (e) thereto as follows
and (ii) relettering existing clauses (e) and (f) as clauses (f) and (g)
respectively:

          "(e)  Credit Rating.  The Guarantor's senior unsecured debt rating
     shall be less than BBB by Standard & Poor's, a division of McGraw Hill
     Company, Inc. or Baa by Moody's Investors Services, Inc.; or"

     3.2.  Section 3 of the Guaranty.  Section 3 of the Guaranty is hereby
amended as of the date hereof by deleting the reference to "Section 2(e) - (f)"
appearing therein and substituting "Section 2(f) - (g)" therefor.

     4.  WARRANTIES.  To induce the Lender to enter into this Amendment, the
Borrower and the Guarantor warrant that:

     4.1.  Authorization.  Such party is duly authorized to execute and
deliver this Amendment and is and will continue to be duly authorized, in the
case of the Borrower, to borrow monies under the Loan Documents, as amended
hereby, and to perform its obligations under the Loan Documents, as amended
hereby, and in the case of the Guarantor, to perform its obligations under the
Guaranty, as amended hereby.

     4.2.  No Conflicts.  The execution and delivery of this Amendment, and the
performance by such party of its obligations, in the case of the Borrower under
the Loan Documents, and in the case of the Gurantor, the Guaranty, each as
amended hereby, do not and will not conflict with any provision of law or of the
charter or by-laws of such party or of any agreement binding upon such party.

     4.3.  Validity and Binding Effect.  The Loan Documents and, in the case
of the Guarantor, the Guaranty, each as amended hereby, are legal, valid and
binding obligations of such party, as applicable, enforceable against such
party, as applicable, in accordance with their terms, except as enforceability
may be limited by bankruptcy, insolvency or other similar laws of general
application affecting the enforcement of creditors' rights or by general
principles of equity limiting the availability of equitable remedies.

                                      -6-
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     5.  CONDITIONS PRECEDENT TO AMENDMENTS.  The amendments contemplated by
Sections 1, 2 and 3 hereof are subject to the satisfaction of each of the
following conditions precedent:

     5.1.  Documentation.  The Borrower shall have delivered to the Lender all
of the following, each duly executed and dated the closing date hereof, in form
and substance satisfactory to the Lender:

     (a)  Certificate. A certificate of the president or chief financial officer
          of the Borrower as to the matters set out in Sections 5.2 and 5.3
          hereof.

     (b)  Amendment.  The Borrower and the Guarantor shall each have executed a
          counterpart of this Amendment and delivered it to the Lender.

     (c)  Other.  Such other documents as the Lender may reasonably request.

     5.2.  No Default.  As of the closing date hereof, no Event of Default or
Unmatured Event of Default under the Loan Documents or Event Requiring Payment
under the Guaranty shall have occurred and be continuing.

     5.3.  Warranties.  As of the closing date hereof, the warranties in the
Loan Documents, the Guaranty and in Section 4 of this Amendment shall be true
and correct as though made on such date, except for such changes as are
specifically permitted under the Loan Documents or the Guaranty.

     6.  GENERAL.

     6.1.  Expenses.  The Borrower agrees to pay the Lender upon demand for all
reasonable expenses, including reasonable attorneys' and legal assistants' fees
(which attorneys and legal assistants may be employees of the Lender), incurred
by the Lender in connection with the preparation, negotiation and execution of
this Amendment and any document required to be furnished herewith.

     6.2.  Law.  THIS AMENDMENT SHALL BE CONSTRUED IN ACCORDANCE WITH AND
GOVERNED BY THE INTERNAL LAWS OF THE STATE OF ILLINOIS.

     6.3.  Successors.  This Amendment shall be binding upon the Borrower, the
Guarantor and the Lender and their respective successors and assigns, and shall
inure to the benefit of the Borrower, the Guarantor and the Lender and the
successors and assigns of the Lender.

     6.4.  Confirmation of the Agreement.  The Loan Documents and the Guaranty,
each as amended hereby, shall remain in full force and effect and are hereby
ratified and confirmed in all respects.

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<PAGE>

     6.5.  References to the Agreement.  Each reference in the Loan Documents
or the Guaranty to "this Agreement," "hereunder," "hereof," or words of similar
import in instruments or documents provided for in the Loan Documents or the
Guaranty or delivered or to be delivered thereunder or in connection therewith,
shall, except where the context otherwise requires, be deemed a reference to the
Loan Documents or the Guaranty, each as amended hereby.

     6.6.  Counterparts.  This Amendment may be executed in any number of
counterparts and any party hereto may execute any one or more counterparts, all
of which shall constitute one and the same instrument.

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<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed at Chicago, Illinois by their respective officers thereunto duly
authorized as of the date first written above.

                                    ONE POINT COMMUNICATIONS CORP.

                                    By:    /s/  John D. Stavig
                                        --------------------------------

                                    Title   Chief Financial Officer
                                          ------------------------------


                                    SBC COMMUNICATIONS, INC.

                                    By:  /s/  (Signature Illegible)
                                        --------------------------------

                                             Director-Corporate Finance,
                                             for Roger W. Wohlert,
                                             Assistant Treasurer,
                                    Title:   pursuant to Delegation
                                           -----------------------------


                                    THE NORTHERN TRUST COMPANY

                                    By:  /s/  Kinley Reddy
                                        --------------------------------

                                    Title   Vice President
                                          ------------------------------



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