CodeSampleX

Sample

verify pkg:npm/error-ex@1.3.4

sha256:cc4fa472e89afc27116cb0e54c50a90e02190325b99610c48ed94bcdfd202f61

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
1
Signing keys that built it
1
Declared environment linux 24 · ubuntu · glibc 2.39 x64 npm

Verification-run environments

Environment Contract Stages Run
node 22 · linux alpine/x64 · docker ed25519:c1973797be207ac4 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1node:22-alpine@sha256:c610fcdfb1d5…
2026-08-23

Case

HOW
Goal
verify pkg:npm/error-ex@1.3.4
Packages
Created
2026-08-23T15:41:58Z

Contract

  1. errorEx creates a custom Error subclass that can be instantiated with or without new
  2. errorEx unwraps message when instantiated with an existing Error instance
  3. errorEx defaults error name to Error when name parameter is omitted or not a string
  4. errorEx.append modifier appends formatted property values to error message
  5. errorEx.line modifier inserts custom formatted line into error stack trace
  6. errorEx instances support message setter and stack setter override

Files

  • PROMPT.md
  • csx.json
  • package-lock.json
  • package.json
  • spec.json
  • test/contract.mjs

Download the source artifact (tar.gz)

Origin Seeder

anonymous