vCon Agent Session Extension

This repository contains the source for an Internet-Draft defining an agent_session extension for the Virtualized Conversation (vCon) standard. The extension specifies how an autonomous AI agent's internal session — its prompts, tool calls, tool results, reasoning, and file or artifact provenance — is carried inside a vCon alongside the human-facing conversation that the agent participated in or acted upon.

Summary

The primary document in this repository is:

• draft-howe-vcon-agent-session: A Compatible vCon extension that bridges vCon and the Verifiable Agent Conversations (VAC) draft (draft-birkholz-verifiable-agent-conversations). It defines:
  • Agents as vCon parties[] entries (role: "agent", meta.agent_session)
  • Agent dialog turns as ordinary dialog[] entries
  • The internal agent trace as analysis[] entries of type: "agent_trace" whose body is a VAC verifiable-agent-record
  • File and artifact provenance as attachments[] with new purpose values (agent_file_change, agent_artifact, agent_environment)
  • Reuse of the existing lawful_basis and lifecycle extensions for consent and redaction

This document is intended for submission to the IETF vCon Working Group.

Status

This document is an active work in progress. Feedback and contributions are welcome.

Repository Structure

• draft-howe-vcon-agent-session.md — kramdown-rfc source of the draft.
• examples/paired-agent-session.json — a worked example vCon: a customer support exchange handled by an AI coding agent, exercising every part of the extension (agent party, dialog turns, embedded VAC trace, file-change attachments, lawful basis).
• Makefile — delegates to the martinthomson/i-d-template toolchain.
• lib/ — toolchain (auto-cloned on first make).

Building

make            # build .html and .txt outputs
make fix-lint   # auto-fix linting issues

The build requires the i-d-template dependencies (xml2rfc, kramdown-rfc, etc.).

Relationship to Other Drafts

• draft-ietf-vcon-vcon-core — the base vCon standard. This extension is Compatible (Section 2.5) and introduces no new top-level fields.
• draft-birkholz-verifiable-agent-conversations — the VAC draft. Its verifiable-agent-record schema is the canonical structure embedded in the agent_trace analysis body.
• draft-howe-vcon-lawful-basis — used unmodified to govern consent for agent session recording, analysis, and redistribution.
• draft-howe-vcon-lifecycle — used unmodified for redaction of individual reasoning entries.

Contributing

Please see CONTRIBUTING.md for details.

Changelog

v0.1.0 — 2026-05-20

• First tagged release of the working draft.
• Defines agent_session as a Compatible vCon extension projecting a VAC verifiable-agent-record into a vCon analysis[] entry.
• Specifies agent representation as a parties[] entry (role: "agent", meta.agent_session), agent dialog turns as ordinary dialog[] entries, and file/artifact provenance via new purpose values (agent_file_change, agent_artifact, agent_environment).
• Adds ARCHITECTURE.md capturing the schema-vs-profile split agreed with Henk Birkholz and Tobias Heldt (2026-05-15).
• Includes examples/paired-agent-session.json — a worked example exercising every part of the extension.
• Wires CI: every example validated as well-formed JSON and against the vCon core JSON Schema; daily VAC CDDL contract check (allowed to fail until upstream CDDL stabilizes).