Sample
ParentBased sampler delegates sampled remote parents to AlwaysSample and unsampled parents to NeverSample by default, overriding the root sampler configuration for any context containing a valid parent span
sha256:53b6e958b9713543736332d7b7f87d665da9d8c7c6468e96529ad968c51148fc
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
- go
- Operating system
- linux
- Architecture
- x64
- Runtime
- go
- Language
- go
- Package manager
- go
Verification-run environments
- Execution context
- go 1.26
- Operating system
- linux alpine · musl
- Architecture
- x64
- Runtime
- go 1.26
- Language
- go
- Package manager
- go
- Execution
- container · docker
CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · golang@1 · 2026-08-17
Case
- Goal
- ParentBased sampler delegates sampled remote parents to AlwaysSample and unsampled parents to NeverSample by default, overriding the root sampler configuration for any context containing a valid parent span HOW
- Packages
-
go.opentelemetry.io/otel/sdk v1.24.0
- Environment
- go
- Created
- 2026-08-17T06:42:33Z
Commonly assumed
ParentBased(NeverSample()) disables span sampling across all spans created by the TracerProvider
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- ParentBased(NeverSample()) samples and exports child spans when the context contains a sampled remote parent, because ParentBased delegates sampled remote parents to AlwaysSample() by default rather than the configured root sampler.
- ParentBased(AlwaysSample()) drops and suppresses child spans when the context contains an unsampled remote or local parent, because ParentBased delegates unsampled parents to NeverSample() by default.
- Only root spans without a valid parent context evaluate the root sampler passed to ParentBased.
- ParentBased.Description() returns a composite string reflecting the root sampler and all four default sub-samplers.
Files
- NOTES.md
- csx.json
- go.mod
- go.sum
- tracer_test.go
Download the source artifact (tar.gz)
Origin Seeder
csx-seed
Verification receipts
- go 1.26 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · golang@1 · 2026-08-17 · ed25519:d91480838ac982c9