Use with Braintrust - typesafe-sdk-go

trace/contrib/typesafe is an HTTP middleware for braintrust-sdk-go that traces every POST /v1/systemone call made through this SDK. It wraps the *http.Client passed to typesafe.WithHTTPClient, so no manual span code is needed in application code.

This package lives on the feat/typesafe-tracing branch of a fork and is not merged upstream yet. The install step below points at that branch directly.

Install

go get github.com/atharvamhaske/braintrust-sdk-go/trace/contrib/typesafe@feat/typesafe-tracing

Usage

tp := trace.NewTracerProvider()
defer tp.Shutdown(context.Background())
otel.SetTracerProvider(tp)

bt, err := braintrust.New(tp, braintrust.WithProject("my-project"))
if err != nil {
    log.Fatal(err)
}

client, err := typesafe.NewClient(
    typesafe.WithHTTPClient(bttypesafe.Client()), // reads TYPESAFE_API_KEY
)
if err != nil {
    log.Fatal(err)
}

// every SystemOne call is now traced automatically
resp, err := client.SystemOne(ctx, state, questions)

Span shape

The middleware matches the span shape the official Python and JS TypeSafe integrations use, not the generic llm shape used for chat completion providers elsewhere in braintrust-sdk-go.

Field	Value
Span name	`typesafe.systemOne`
`braintrust.span_attributes.type`	`question`
`braintrust.input_json`	`state`, plus `questions` as an id-tagged list
`braintrust.output_json`	`answers` as an id-tagged list
`braintrust.metadata`	`provider: "typesafe"`, `model`
`braintrust.metrics`	`prompt_tokens`, `completion_tokens`, `tokens`, from `usage`

Full runnable example

examples/braintrust/main.go. It has its own go.mod, so braintrust-sdk-go and OpenTelemetry stay out of the core SDK’s dependency graph.

Custom TracerProvider

httpClient := bttypesafe.Client(bttypesafe.WithTracerProvider(tp))
client, err := typesafe.NewClient(typesafe.WithHTTPClient(httpClient))

Any other OpenTelemetry backend

The middleware sets standard OpenTelemetry span attributes, so it works with Datadog, Honeycomb, or a raw OTel collector too. Only the braintrust.* attribute names are Braintrust-specific.