What is the test for standing to enforce a third party's contractual obligations?

Co. (1999) 74 Cal.App.4th 401, 405 ["It is elementary that a party asserting a claim must have standing to do so. In asserting a claim based upon a contract, this generally requires the party to be a signatory to the contract, or to be an intended third party beneficiary"].) "'"'A third party should not be permitted to enforce covenants made not for his benefit, but rather for others. He is not a contracting party; his right to performance is predicated on the contracting parties' intent to benefit him . . . .'" [Citations.]' [Citation.]" (California Emergency Physicians Medical Group v. PacifiCare of California (2003) 111 Cal.App.4th 1127, 1138 (Emergency Physicians).)