Kest LogoKest
Get Started

Context Helpers

Read the current Kest execution context from anywhere in your call stack.

The kest.core.framework.context module provides helper functions for reading the current Kest execution context from within any function in the call stack, without explicitly threading state through function arguments.

All values are read from the OpenTelemetry Baggage attached to the current context.

get_current_jwt() -> Optional[str]

Returns the raw JWT token (kest.jwt baggage key). This is the full Bearer token stored by KestIdentityMiddleware for downstream verification. Treat with appropriate care — this is a sensitive credential.

python
from kest.core.framework.context import get_current_jwt
 
jwt = get_current_jwt()
if jwt:
    # Verify with your chosen JWT library (PyJWT, python-jose, etc.)
    ...

Returns None if no JWT is in context.

get_current_passport() -> Optional[str]

Returns the serialised Kest Passport (kest.passport baggage key). The Passport is the packed Merkle chain of JWS signatures accumulated across all hops.

python
from kest.core.framework.context import get_current_passport
 
passport_b64 = get_current_passport()
# Use PassportVerifier to validate
from kest.core import PassportVerifier
verifier = PassportVerifier()
is_valid = verifier.verify(passport_b64, expected_root="...")

Accessing Other Baggage

Under the hood, helpers call baggage.get_baggage(key) using the current OpenTelemetry context. You can retrieve other context variables manually:

python
from opentelemetry import baggage
 
user = baggage.get_baggage("kest.user")
agent = baggage.get_baggage("kest.agent")
task = baggage.get_baggage("kest.task")
Baggage KeySet by
kest.userKestIdentityMiddleware (JWT sub claim)
kest.agentKestIdentityMiddleware (JWT client_id claim)
kest.taskKestIdentityMiddleware (JWT scope claim)
kest.jwtKestIdentityMiddleware
kest.passport@kest_verified decorator
kest.passport_z@kest_verified (compressed inline, Tier 2)
kest.claim_check@kest_verified (Claim Check UUID, Tier 3)
kest.chain_tip@kest_verified (SHA-256 of last entry)

Hardening note (2026-04-11): Baggage keys were renamed for spec compliance. Old key names (kest.principal_user, kest.workload_agent, kest.scope) are no longer written. Rebuild all services together when upgrading.

See Also