A method for machine-implemented assistance of interaction among a plurality of parties, the method comprising: Monitoring, by a communication intermediary application, communication among the plurality of parties, the plurality of parties including a user and an agent, the communication including at least some part related to forming of an agreement between at least some of the parties; forming, using a machine-implemented process, evidence of the agreement based on the monitoring of the communication; forming, based on at least some of the formed evidence, a digital record, the method characterized by forming a digital evidence record including a cryptographic signature of the digital record; storing at least part of the formed evidence as the digital record in a content store of a ledger; storing the cryptographic signature of the digital record of the digital evidence record in an immutable blockchain-based public distributed ledger, the cryptographic signature being associated with the digital record through an index maintained by the ledger, the public distributed immutable ledger being different from the content store of the ledger, wherein the cryptographic signature is configured to authenticate the at least part of the formed evidence stored in the content store when subsequently retrieved for use in a future dispute resolution involving the agreement; retrieving, for a purpose of resolving a dispute related to the agreement, the formed evidence and digital evidence record; and recovering from the retrieved and authenticated formed evidence, by a machine-implemented question answering system, items of evidence formatted as answers to questions made during the dispute resolution interaction regarding the forming of the agreement. Monitoring, by a communication intermediary application, communication among the plurality of parties, the plurality of parties including a user and an agent, the communication including at least some part related to forming of an agreement between at least some of the parties; forming, using a machine-implemented process, evidence of the agreement based on the monitoring of the communication; forming, based on at least some of the formed evidence, a digital record, the method characterized by forming a digital evidence record including a cryptographic signature of the digital record; storing at least part of the formed evidence as the digital record in a content store of a ledger; storing the cryptographic signature of the digital record of the digital evidence record in an immutable blockchain-based public distributed ledger, the cryptographic signature being associated with the digital record through an index maintained by the ledger, the public distributed immutable ledger being different from the content store of the ledger, wherein the cryptographic signature is configured to authenticate the at least part of the formed evidence stored in the content store when subsequently retrieved for use in a future dispute resolution involving the agreement; retrieving, for a purpose of resolving a dispute related to the agreement, the formed evidence and digital evidence record; and recovering from the retrieved and authenticated formed evidence, by a machine-implemented question answering system, items of evidence formatted as answers to questions made during the dispute resolution interaction regarding the forming of the agreement.