Agent passport — portable identity across frameworks

13. Agent passport — portable identity across frameworks

An agent’s capability statement says what the agent claims about itself. An agent passport adds the vouch: the issuing organisation countersigns it, and that issuer is resolvable in the shared Trust Registry. One portable signed file then tells any verifier, in any framework, the same thing:

“Org X (an issuer the registry knows) vouches that agent:billing.bot holds key K and may use tools/models Z, until time T.”

pip install 'raucle[compliance]'

Issue (the org, once per agent)

# The org's issuer key is published to the registry; it signs the passport.
raucle passport issue agent-statement.json \
  --issuer-key org.key.pem --issuer "Org X" --ttl 2592000 --out agent.passport.json

from raucle.passport import issue_passport

passport = issue_passport(
    agent.statement, issuer_signer=org_signer, issuer="Org X", ttl_seconds=30 * 86400
)
passport.save("agent.passport.json")

Verify (anyone, in any framework)

raucle passport verify agent.passport.json --registry https://trust.example.com/registry.jsonl
# VALID  agent:billing.bot  (issuer: Org X)
#   allowed tools: lookup_invoice, send_email

from raucle.passport import verify_passport

v = verify_passport(passport.to_dict(), registry=shared_registry)
if v.valid:
    # trust v.agent_id <-> v.key_id, enforce v.allowed_tools / v.allowed_models
    ...

The same passport works wherever the agent runs — LangChain, CrewAI, Agent Framework, MCP, A2A. Each integration verifies it once against the registry, then enforces the agent’s declared scope.

Fail-closed by construction

verify_passport is invalid (never silently trusted) when:

• the issuer is unknown or revoked in the registry (resolves to no active key),
• the issuer signature does not verify,
• the passport has expired,
• the version or any statement field was tampered (the whole body is signed, so editing allowed_tools to add transfer_funds breaks verification).

Revoking the issuer’s key in the registry invalidates every passport it signed, everywhere, with no per-passport coordination.

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Built on the Trust Registry (P1) and the existing AgentIdentity / CapabilityStatement. This is the cross-framework identity layer platforms adopt.