Sample
Setting maxTokenAge in jwtVerify enforces mandatory presence of the iat claim, rejecting tokens without iat via JWTClaimValidationFailed even if unexpired by exp, and rejects future iat timestamps unless clockTolerance is configured.
sha256:c6472d96d7e2e72142939fca93662b5d075d9d1c3adbbc3c931bef9e445d6d93
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Execution evidence
Declared environment and signed verification runs are separated so you can see exactly what this sample proves.
Evidence basisSigned contract pass
Verification receipts1
Verification levelL3_CONTRACT_PASS
Declared environment
- Execution context
- node
- Operating system
- linux
- Architecture
- x64
- Runtime
- node
- Language
- node
- Package manager
- npm
Verification-run environments
- Execution context
- node 22
- Operating system
- linux alpine · musl
- Architecture
- x64
- Runtime
- node 22
- Language
- javascript
- Package manager
- npm
- Execution
- container · docker
CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-17
Case
- Goal
- Setting maxTokenAge in jwtVerify enforces mandatory presence of the iat claim, rejecting tokens without iat via JWTClaimValidationFailed even if unexpired by exp, and rejects future iat timestamps unless clockTolerance is configured. HOW
- Packages
-
jose 6.2.9
- Environment
- node
- Created
- 2026-08-17T11:14:47Z
Commonly assumed
Setting maxTokenAge only limits allowable token age when an iat claim is present, falling back to exp expiration checking when iat is omitted.
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- jwtVerify with maxTokenAge configured rejects tokens lacking an iat claim with JWTClaimValidationFailed and reason 'missing' rather than falling back to exp validation.
- jwtVerify with maxTokenAge rejects future iat timestamps with JWTClaimValidationFailed and reason 'check_failed' unless clockTolerance absorbs the clock skew.
- jwtVerify with maxTokenAge throws JWTExpired with claim 'iat' when current time exceeds iat plus maxTokenAge, even if the exp claim has not expired.
- jwtVerify accepts valid tokens whose age is within maxTokenAge bounds.
- jwtVerify rejects unsupported duration units such as milliseconds ('500ms') in maxTokenAge with a TypeError.
Files
- NOTES.md
- csx.json
- package-lock.json
- package.json
- test/contract.mjs
Download the source artifact (tar.gz)
Origin Seeder
csx-seed
Verification receipts
- node 22 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-17 · ed25519:d91480838ac982c9