HDP-P
HDP extended to physical AI: robots, vehicles, surgical systems.
HDP-P extends the HDP trust model to embodied agents. It introduces the Embodied Delegation Token, a four-class irreversibility classification, and mandatory pre-execution authorization for actions in the physical world.
- Status
- Draft companion spec
- Version
- 0.1
- Base protocol
- HDP
- License
- CC BY 4.0
- DOI
- 10.5281/zenodo.19332440
The idea
A prompt injection that leaks data is recoverable. A robot arm that moves into a person is not. HDP-P extends HDP’s trust model to embodied agents — treating physical irreversibility as a security property.
Authorization is checked before an action executes, not audited after it.
What HDP-P adds
Four mechanisms on top of HDP, all bound into a single signed token before the agent may actuate.
Irreversibility classification
A four-class scale from reversible to catastrophic; actions above a ceiling need confirmation or are prohibited.
Embodied Delegation Token
An EDT binds intent to a specific machine, workspace, force and velocity limits, and excluded zones.
Policy attestation
Every action carries the policy hash, training-run id, and sim-validation status it was cleared under.
Fleet delegation scope
Explicit limits on sub-delegation depth and which agents an authorization may pass to.
An Embodied Delegation Token
Intent bound to a physical envelope: permitted actions, excluded zones, force limits, and an irreversibility ceiling.
{
"hdp": "0.1",
"scope": {
"intent": "Pick and place parts in assembly cell 3.",
"authorized_tools": ["move_arm", "grip", "sensor_read"]
},
"hdp-p": {
"embodiment": { "type": "manipulator", "platform": "UR10e" },
"action_scope": {
"permitted_actions": ["pick", "place", "grip_open", "grip_close"],
"excluded_zones": ["zone_personnel_A", "zone_electrical_cabinet"],
"force_limit_n": 50,
"max_velocity_ms": 0.25
},
"irreversibility": {
"max_class": 1,
"class2_requires_confirmation": true,
"class3_prohibited": true
},
"policy_attestation": { "policy_hash": "sha256:a1b2c3…", "sim_validated": true }
},
"signature": { "alg": "Ed25519", "kid": "key-1", "value": "…" }
}Published in the open
HDP-P is a companion specification, published on Zenodo (10.5281/zenodo.19332440), with a public Hugging Face demo that blocks unsafe actuator commands before execution. See the announcement, or the base protocol HDP.
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