Add LangChainGo OpenAI provider to auto-instrumentation

README.md

@@ -53,6 +53,7 @@ import (
     _ "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/openai"    // OpenAI (openai-go)
     _ "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/anthropic" // Anthropic
     _ "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/genai"     // Google GenAI
+    _ "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/langchaingo" // LangChainGo OpenAI
     _ "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/github.com/sashabaranov/go-openai" // sashabaranov/go-openai
 )
 ```

examples/internal/autoinstrumentation/go.mod

@@ -1,6 +1,6 @@
 module github.com/braintrustdata/braintrust-sdk-go/examples/internal/autoinstrumentation
 
-go 1.24.0
+go 1.24.4
 
 toolchain go1.24.11
 
@@ -51,6 +51,7 @@ require (
 	github.com/clipperhouse/uax29/v2 v2.3.0 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.7 // indirect
 	github.com/dave/dst v0.27.3 // indirect
+	github.com/dlclark/regexp2 v1.10.0 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/ebitengine/purego v0.9.0 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
@@ -71,7 +72,7 @@ require (
 	github.com/hashicorp/go-version v1.7.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/compress v1.18.1 // indirect
-	github.com/klauspost/cpuid/v2 v2.2.7 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.9 // indirect
 	github.com/lucasb-eyer/go-colorful v1.3.0 // indirect
 	github.com/lufia/plan9stats v0.0.0-20251013123823-9fd1530e3ec3 // indirect
 	github.com/mattn/go-colorable v0.1.14 // indirect
@@ -90,6 +91,7 @@ require (
 	github.com/outcaste-io/ristretto v0.2.3 // indirect
 	github.com/philhofer/fwd v1.2.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
+	github.com/pkoukk/tiktoken-go v0.1.6 // indirect
 	github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 // indirect
 	github.com/polyfloyd/go-errorlint v1.8.1-0.20250906200200-9b25878c4dea // indirect
 	github.com/power-devops/perfstat v0.0.0-20240221224432-82ca36839d55 // indirect
@@ -108,6 +110,7 @@ require (
 	github.com/tinylib/msgp v1.4.0 // indirect
 	github.com/tklauser/go-sysconf v0.3.15 // indirect
 	github.com/tklauser/numcpus v0.10.0 // indirect
+	github.com/tmc/langchaingo v0.1.14 // indirect
 	github.com/urfave/cli/v2 v2.27.7 // indirect
 	github.com/xeipuuv/gojsonpointer v0.0.0-20190905194746-02993c407bfb // indirect
 	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect

examples/internal/autoinstrumentation/go.sum

@@ -88,6 +88,8 @@ github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8Yc
 github.com/dgryski/go-farm v0.0.0-20190423205320-6a90982ecee2/go.mod h1:SqUrOPUnsFjfmXRMNPybcSiG0BgUW2AuFH8PAnS2iTw=
 github.com/dgryski/go-farm v0.0.0-20240924180020-3414d57e47da h1:aIftn67I1fkbMa512G+w+Pxci9hJPB8oMnkcP3iZF38=
 github.com/dgryski/go-farm v0.0.0-20240924180020-3414d57e47da/go.mod h1:SqUrOPUnsFjfmXRMNPybcSiG0BgUW2AuFH8PAnS2iTw=
+github.com/dlclark/regexp2 v1.10.0 h1:+/GIL799phkJqYW+3YbOd8LCcbHzT0Pbo8zl70MHsq0=
+github.com/dlclark/regexp2 v1.10.0/go.mod h1:DHkYz0B9wPfa6wondMfaivmHpzrQ3v9q8cnmRbL6yW8=
 github.com/dustin/go-humanize v1.0.0/go.mod h1:HtrtbFcZ19U5GC7JDqmcUSB87Iq5E25KnS6fMYU6eOk=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
@@ -142,6 +144,7 @@ github.com/klauspost/compress v1.18.1 h1:bcSGx7UbpBqMChDtsF28Lw6v/G94LPrrbMbdC3J
 github.com/klauspost/compress v1.18.1/go.mod h1:ZQFFVG+MdnR0P+l6wpXgIL4NTtwiKIdBnrBd8Nrxr+0=
 github.com/klauspost/cpuid/v2 v2.2.7 h1:ZWSB3igEs+d0qvnxR/ZBzXVmxkgt8DdzP6m9pfuVLDM=
 github.com/klauspost/cpuid/v2 v2.2.7/go.mod h1:Lcz8mBdAVJIBVzewtcLocK12l3Y+JytZYpaMropDUws=
+github.com/klauspost/cpuid/v2 v2.2.9/go.mod h1:rqkxqrZ1EhYM9G+hXH7YdowN5R5RGN6NK4QwQ3WMXF8=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
 github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
@@ -202,6 +205,8 @@ github.com/philhofer/fwd v1.2.0 h1:e6DnBTl7vGY+Gz322/ASL4Gyp1FspeMvx1RNDoToZuM=
 github.com/philhofer/fwd v1.2.0/go.mod h1:RqIHx9QI14HlwKwm98g9Re5prTQ6LdeRQn+gXJFxsJM=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pkoukk/tiktoken-go v0.1.6 h1:JF0TlJzhTbrI30wCvFuiw6FzP2+/bR+FIxUdgEAcUsw=
+github.com/pkoukk/tiktoken-go v0.1.6/go.mod h1:9NiV+i9mJKGj1rYOT+njbv+ZwA/zJxYdewGl6qVatpg=
 github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 h1:GFCKgmp0tecUJ0sJuv4pzYCqS9+RGSn52M3FUwPs+uo=
 github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10/go.mod h1:t/avpk3KcrXxUnYOhZhMXJlSEyie6gQbtLq5NM3loB8=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
@@ -269,6 +274,8 @@ github.com/tklauser/go-sysconf v0.3.15 h1:VE89k0criAymJ/Os65CSn1IXaol+1wrsFHEB8O
 github.com/tklauser/go-sysconf v0.3.15/go.mod h1:Dmjwr6tYFIseJw7a3dRLJfsHAMXZ3nEnL/aZY+0IuI4=
 github.com/tklauser/numcpus v0.10.0 h1:18njr6LDBk1zuna922MgdjQuJFjrdppsZG60sHGfjso=
 github.com/tklauser/numcpus v0.10.0/go.mod h1:BiTKazU708GQTYF4mB+cmlpT2Is1gLk7XVuEeem8LsQ=
+github.com/tmc/langchaingo v0.1.14 h1:o1qWBPigAIuFvrG6cjTFo0cZPFEZ47ZqpOYMjM15yZc=
+github.com/tmc/langchaingo v0.1.14/go.mod h1:aKKYXYoqhIDEv7WKdpnnCLRaqXic69cX9MnDUk72378=
 github.com/urfave/cli/v2 v2.27.7 h1:bH59vdhbjLv3LAvIu6gd0usJHgoTTPhCFib8qqOwXYU=
 github.com/urfave/cli/v2 v2.27.7/go.mod h1:CyNAG/xg+iAOg0N4MPGZqVmv2rCoP267496AOXUZjA4=
 github.com/vmihailenco/msgpack/v4 v4.3.13 h1:A2wsiTbvp63ilDaWmsk2wjx6xZdxQOvpiNlKBGKKXKI=

examples/internal/autoinstrumentation/main.go

@@ -4,8 +4,9 @@
 //   - OpenAI (openai-go official SDK)
 //   - Anthropic
 //   - sashabaranov/go-openai
+//   - LangChainGo (OpenAI provider)
 //
-// Note: NO manual middleware is added to any client.
+// Note: NO manual middleware or callbacks are added to any client.
 // When built with `orchestrion go build`, tracing middleware is injected at compile time.
 //
 // To run:
@@ -25,6 +26,8 @@ import (
 	"github.com/anthropics/anthropic-sdk-go"
 	"github.com/openai/openai-go"
 	sashabaranov "github.com/sashabaranov/go-openai"
+	"github.com/tmc/langchaingo/llms"
+	langchainopenai "github.com/tmc/langchaingo/llms/openai"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/sdk/trace"
 
@@ -71,6 +74,10 @@ func main() {
 	fmt.Println("3. sashabaranov/go-openai...")
 	runSashabaranov(ctx)
 
+	// 4. LangChainGo - NO callback added
+	fmt.Println("4. LangChainGo (OpenAI)...")
+	runLangChainGo(ctx)
+
 	fmt.Println("\n=== All providers tested ===")
 	fmt.Println("If tracing worked, you should see LLM spans for each provider in Braintrust.")
 	fmt.Printf("View trace: %s\n", bt.Permalink(rootSpan))
@@ -128,3 +135,21 @@ func runSashabaranov(ctx context.Context) {
 	}
 	fmt.Printf("   Response: %s\n", resp.Choices[0].Message.Content)
 }
+
+func runLangChainGo(ctx context.Context) {
+	// NO callback - Orchestrion injects it
+	llm, err := langchainopenai.New()
+	if err != nil {
+		log.Printf("   LangChainGo error: %v", err)
+		return
+	}
+
+	resp, err := llm.GenerateContent(ctx, []llms.MessageContent{
+		llms.TextParts(llms.ChatMessageTypeHuman, "Say 'Hello from LangChainGo' in exactly those words."),
+	})
+	if err != nil {
+		log.Printf("   LangChainGo error: %v", err)
+		return
+	}
+	fmt.Printf("   Response: %s\n", resp.Choices[0].Content)
+}

internal/genorchestrion/genorchestrion_test.go

@@ -41,6 +41,7 @@ func TestGenerate(t *testing.T) {
 		"anthropic-newclient-middleware",
 		"sashabaranov-newclientwithconfig-wrap",
 		"genai-newclient-wrap",
+		"langchaingo-openai-newllm-callback",
 	}
 
 	for _, expected := range expectedAspects {
@@ -74,10 +75,10 @@ func TestGenerateExcludesAllDirectory(t *testing.T) {
 		t.Fatalf("Failed to parse generated YAML: %v", err)
 	}
 
-	// Count aspects - should be exactly 5 (one per provider, plus openai-v2)
+	// Count aspects - should be exactly 6 (one per provider, plus openai-v2)
 	// If it's more, we might be including duplicates from all/
-	if len(result.Aspects) != 5 {
-		t.Errorf("expected 5 aspects, got %d", len(result.Aspects))
+	if len(result.Aspects) != 6 {
+		t.Errorf("expected 6 aspects, got %d", len(result.Aspects))
 	}
 }
 

trace/contrib/README.md

@@ -8,6 +8,9 @@ Set up OpenTelemetry and initialize Braintrust:
 
 ```go
 import (
+    "context"
+    "log"
+
     "go.opentelemetry.io/otel"
     "go.opentelemetry.io/otel/sdk/trace"
     "github.com/braintrustdata/braintrust-sdk-go"
@@ -30,86 +33,129 @@ func main() {
 
 ```go
 import (
+    "context"
+
     "github.com/openai/openai-go"
     "github.com/openai/openai-go/option"
     traceopenai "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/openai"
 )
 
-client := openai.NewClient(
-    option.WithMiddleware(traceopenai.NewMiddleware()),
-)
-
-_, err := client.Chat.Completions.New(ctx, openai.ChatCompletionNewParams{
-    Messages: []openai.ChatCompletionMessageParamUnion{
-        openai.UserMessage("Hello!"),
-    },
-    Model: openai.ChatModelGPT4oMini,
-})
+func main() {
+    ctx := context.Background()
+    client := openai.NewClient(
+        option.WithMiddleware(traceopenai.NewMiddleware()),
+    )
+
+    _, _ = client.Chat.Completions.New(ctx, openai.ChatCompletionNewParams{
+        Messages: []openai.ChatCompletionMessageParamUnion{
+            openai.UserMessage("Hello!"),
+        },
+        Model: openai.ChatModelGPT4oMini,
+    })
+}
 ```
 
 ## Anthropic
 
 ```go
 import (
+    "context"
+
     "github.com/anthropics/anthropic-sdk-go"
     "github.com/anthropics/anthropic-sdk-go/option"
     traceanthropic "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/anthropic"
 )
 
-client := anthropic.NewClient(
-    option.WithMiddleware(traceanthropic.NewMiddleware()),
-)
-
-_, err := client.Messages.New(ctx, anthropic.MessageNewParams{
-    Model: anthropic.ModelClaude3_7SonnetLatest,
-    Messages: []anthropic.MessageParam{
-        anthropic.NewUserMessage(anthropic.NewTextBlock("Hello!")),
-    },
-    MaxTokens: 1024,
-})
+func main() {
+    ctx := context.Background()
+    client := anthropic.NewClient(
+        option.WithMiddleware(traceanthropic.NewMiddleware()),
+    )
+
+    _, _ = client.Messages.New(ctx, anthropic.MessageNewParams{
+        Model: anthropic.ModelClaude3_7SonnetLatest,
+        Messages: []anthropic.MessageParam{
+            anthropic.NewUserMessage(anthropic.NewTextBlock("Hello!")),
+        },
+        MaxTokens: 1024,
+    })
+}
 ```
 
 ## Google Gemini
 
 ```go
 import (
+    "context"
+    "os"
+
     "google.golang.org/genai"
     tracegenai "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/genai"
 )
 
-client, err := genai.NewClient(ctx, &genai.ClientConfig{
-    HTTPClient: tracegenai.Client(),
-    APIKey:     os.Getenv("GOOGLE_API_KEY"),
-    Backend:    genai.BackendGeminiAPI,
-})
-
-_, err = client.Models.GenerateContent(ctx,
-    "gemini-1.5-flash",
-    genai.Text("Hello!"),
-    nil,
-)
+func main() {
+    ctx := context.Background()
+    client, _ := genai.NewClient(ctx, &genai.ClientConfig{
+        HTTPClient: tracegenai.Client(),
+        APIKey:     os.Getenv("GOOGLE_API_KEY"),
+        Backend:    genai.BackendGeminiAPI,
+    })
+
+    _, _ = client.Models.GenerateContent(ctx,
+        "gemini-1.5-flash",
+        genai.Text("Hello!"),
+        nil,
+    )
+}
 ```
 
 ## sashabaranov/go-openai
 
 ```go
 import (
+    "context"
+    "os"
+
     "github.com/sashabaranov/go-openai"
     traceopenai "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/github.com/sashabaranov/go-openai"
 )
 
-config := openai.DefaultConfig(os.Getenv("OPENAI_API_KEY"))
-config.HTTPClient = traceopenai.Client()
-client := openai.NewClientWithConfig(config)
-
-_, err := client.CreateChatCompletion(ctx, openai.ChatCompletionRequest{
-    Model: openai.GPT4oMini,
-    Messages: []openai.ChatCompletionMessage{
-        {Role: openai.ChatMessageRoleUser, Content: "Hello!"},
-    },
-})
+func main() {
+    ctx := context.Background()
+    config := openai.DefaultConfig(os.Getenv("OPENAI_API_KEY"))
+    config.HTTPClient = traceopenai.Client()
+    client := openai.NewClientWithConfig(config)
+
+    _, _ = client.CreateChatCompletion(ctx, openai.ChatCompletionRequest{
+        Model: openai.GPT4oMini,
+        Messages: []openai.ChatCompletionMessage{
+            {Role: openai.ChatMessageRoleUser, Content: "Hello!"},
+        },
+    })
+}
 ```
 
 ## LangChainGo
 
-See [`examples/langchaingo`](../../examples/langchaingo/main.go) for LangChainGo integration with callback-based tracing.
+```go
+import (
+    "context"
+
+    "github.com/tmc/langchaingo/llms"
+    "github.com/tmc/langchaingo/llms/openai"
+    tracelangchaingo "github.com/braintrustdata/braintrust-sdk-go/trace/contrib/langchaingo"
+)
+
+func main() {
+    ctx := context.Background()
+    handler := tracelangchaingo.NewHandler()
+    llm, _ := openai.New(openai.WithCallback(handler))
+
+    _, _ = llm.GenerateContent(ctx, []llms.MessageContent{
+        llms.TextParts(llms.ChatMessageTypeHuman, "Hello!"),
+    })
+}
+```
+
+For richer traces, use `NewHandlerWithOptions` with `TracerProvider`, `Model`, and `Provider` options.
+See [`examples/langchaingo`](../../examples/langchaingo/main.go) for complete examples.

trace/contrib/all/orchestrion.yml

@@ -53,6 +53,17 @@ aspects:
               __config.HTTPClient = traceopenai.WrapHTTPDoer(__config.HTTPClient)
               return openai.NewClientWithConfig(__config)
             }()
+  - id: langchaingo-openai-newllm-callback
+    join-point:
+      function-call: github.com/tmc/langchaingo/llms/openai.New
+    advice:
+      - append-args:
+          type: github.com/tmc/langchaingo/llms/openai.Option
+          values:
+            - imports:
+                tracelangchaingo: github.com/braintrustdata/braintrust-sdk-go/trace/contrib/langchaingo
+                openai: github.com/tmc/langchaingo/llms/openai
+              template: openai.WithCallback(tracelangchaingo.NewOpenAIHandler())
   - id: openai-newclient-middleware
     join-point:
       function-call: github.com/openai/openai-go.NewClient

trace/contrib/langchaingo/orchestrion.yml

@@ -0,0 +1,17 @@
+# yaml-language-server: $schema=https://datadoghq.dev/orchestrion/schema.json
+meta:
+  name: github.com/braintrustdata/braintrust-sdk-go/trace/contrib/langchaingo
+  description: Auto-instrumentation for LangChainGo OpenAI provider with Braintrust tracing
+
+aspects:
+  - id: langchaingo-openai-newllm-callback
+    join-point:
+      function-call: github.com/tmc/langchaingo/llms/openai.New
+    advice:
+      - append-args:
+          type: github.com/tmc/langchaingo/llms/openai.Option
+          values:
+            - imports:
+                tracelangchaingo: github.com/braintrustdata/braintrust-sdk-go/trace/contrib/langchaingo
+                openai: github.com/tmc/langchaingo/llms/openai
+              template: openai.WithCallback(tracelangchaingo.NewOpenAIHandler())

trace/contrib/langchaingo/tracelangchaingo.go

@@ -109,6 +109,18 @@ func NewHandler() *Handler {
 	}
 }
 
+// NewOpenAIHandler creates a new Handler pre-configured for the LangChainGo OpenAI provider.
+// This is used by auto-instrumentation to provide correct provider metadata.
+func NewOpenAIHandler() *Handler {
+	return &Handler{
+		spans:         make(map[context.Context][]spanEntry),
+		streamBuffers: make(map[string]*strings.Builder),
+		opts: HandlerOptions{
+			Provider: "openai",
+		},
+	}
+}
+
 // NewHandlerWithOptions creates a new Handler with custom options.
 func NewHandlerWithOptions(opts HandlerOptions) *Handler {
 	return &Handler{