Collusion Carriers and Countermeasures: Tool-Action Metadata and SERAPH Governance
Amber Anson · Team AmberContinuum Research
Submitted to AI Collusion Research Sprint. Sprint projects are early-stage work by participants, not Apart Research publications.
We investigated whether AI agents could coordinate through metadata attached to legitimate tool actions, and whether SERAPH governance could restrict that information flow while preserving task execution. We built research adapters over the unchanged SERAPH core and tested a five-condition task-allocation experiment, a private-text coordination control, and a three-condition private-bit allocation experiment.
The private-text control showed explicit coordination. In both metadata experiments, however, agents consistently selected zero rather than developing a varying signal. Governed and ungoverned outcomes matched, so the results do not establish collusion prevention. Even after the final communication calibration passed at 7/8 correct decisions, all three main conditions achieved 4/8 correct allocations.
The positive engineering result was an auditable integration: SERAPH executed 32 verified permits covering functional actions and information disclosure in the final experiment. We contribute reproducible code, recorded model exchanges, protocols, and audit evidence demonstrating research-domain integration while clearly separating successful governance execution from unproven behavioral effectiveness.
Reviews
This paper asks a precise question and is disciplined about what its results can’t show. Calibrating communication before the main run, retaining failed attempts, and refusing to present a null result as prevention are all strong practices. The separation of functional computation from disclosure is also a clear governance idea.
The main limitation is that the study never gets a varying signal into the carrier, so the governance arms have nothing to remove. Once every sender chooses zero, the arms deliver the same information and can’t produce different results. To answer the prevention question, I’d suggest:
Build a positive control: Assign a code, script a sender that varies the field, or tell agents that peers can see it. First show that the ungated channel improves coalition outcomes, then test whether canonicalization removes that gain.
Add intermediate conditions: The study jumps from explicit private text to an unassigned code. Steps such as a disclosed field, a suggested codebook, repeated rounds, or optimization pressure could locate where signaling breaks down.
Widen model and sampling conditions: A single small model, mostly at temperature 0, may strongly favor the default symbol. Testing other models and non-zero temperatures would help separate lack of incentive from lack of capability.
Compare against the plain canonicalizer on real signals: The host-canonical arm produces the same view without SERAPH permits, so the added value of SERAPH needs a test where the two could differ, such as tampering or failed verification.
Test other carriers: Canonicalizing declared fields leaves tool choice, timing, and argument selection open, and these may be more realistic action-based channels.
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Cite this project
@misc{anson2026collusion,
title = {{Collusion Carriers and Countermeasures: Tool-Action Metadata and SERAPH Governance}},
author = {Amber Anson},
year = {2026},
month = oct,
note = {Submitted to AI Collusion Research Sprint, an Apart Research Sprint},
howpublished = {\url{https://apartresearch.com/sprints/projects/collusion-carriers-and-countermeasures-toolaction-metadata-and-seraph-governance-j4w7}},
url = {https://apartresearch.com/sprints/projects/collusion-carriers-and-countermeasures-toolaction-metadata-and-seraph-governance-j4w7}
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