A pre-registered red-team benchmark measuring whether you can still prove which agent did what in a multi-agent AI system once one agent starts impersonating another. Defenses are arranged on a B1–B9 gradient — from shared credentials to sender-constrained tokens and 2026 agent-identity specs — and each version of the benchmark asks where attribution actually holds.
The gap — token exchange has no executor field
OAuth 2.0 Token Exchange (RFC 8693) carries no field naming who actually executes a request. Attribution regresses from B2 to B3, and tamper-evident logs (B4) do not recover it — logs faithfully record the wrong agent.
The fix — sender-constrained tokens
DPoP (RFC 9449) binds each token to the executor's cryptographic key. Attribution recovers at B5, validated against independent OS-process ground truth rather than anything an agent self-reports.
The 2026 finding — self-report collapses under collusion
The new agent-identity drafts (AIP / PEDIGREE / HDP) trust the executor's self-report. B8 collapses when agents collude — while the sender-constrained baselines from v2 keep attribution intact.
- SHA-256-locked pre-registration — committed before measurement code existed
- Mechanical CI gate · 95 passing tests
- 4-agent adversarial self-review with anti-fabrication controls
- Every spec claim source-verified against RFC 8693 / 9449 / 8705 / 8707, MCP, AIP / PEDIGREE / HDP
- Published validity-threats analysis — measured vs. by-construction
Status // v1 + v2 papers written · v3 measured · v3.1 (real-LLM attacker tier) in pre-registration