From eaffad12e7b5dfc47f629f2a32b4420dc03cbdd3 Mon Sep 17 00:00:00 2001
From: Aakash Bakhle <48802744+aakashb95@users.noreply.github.com>
Date: Wed, 3 Jun 2026 16:45:19 +0530
Subject: [PATCH] feat(langfuse): propagate observation metadata for evals
(#14634)
# Pull Request Template
## Description
We need to pass on trace level attributes down to the spans inside them
like tool calls, observations, etc.
This way, we can filter observations based on trace level attributes.
## Type of change
- [x] Bug fix (non-breaking change which fixes an issue)
## How Has This Been Tested?
Please describe the tests that you ran to verify your changes. Provide
instructions so we can reproduce. Please also list any relevant details
for your test configuration.
Attributes added to observation metadata for easy filtering
added a `generation_stage` to differentiate llm_calls that call tools vs
those that generate a `final_response`
propagated attributes to tool calls for future use
## Checklist:
- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [x] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [x] Any dependent changes have been merged and published in downstream
modules
---
.../captain/chat_generation_recorder.rb | 15 +++-
lib/captain/tool_instrumentation.rb | 19 ++---
lib/integrations/llm_instrumentation.rb | 38 +++-------
.../llm_instrumentation_completion_helpers.rb | 8 --
.../llm_instrumentation_constants.rb | 1 +
.../llm_instrumentation_context.rb | 41 ++++++++++
.../llm_instrumentation_helpers.rb | 53 +++++++++++--
lib/integrations/llm_instrumentation_spans.rb | 19 +++++
lib/opentelemetry_config.rb | 5 +-
.../llm/assistant_chat_service_spec.rb | 24 ++++++
.../integrations/llm_instrumentation_spec.rb | 75 ++++++++++++++++++-
11 files changed, 246 insertions(+), 52 deletions(-)
create mode 100644 lib/integrations/llm_instrumentation_context.rb
diff --git a/enterprise/app/helpers/captain/chat_generation_recorder.rb b/enterprise/app/helpers/captain/chat_generation_recorder.rb
index cd631fb16..63bcdc276 100644
--- a/enterprise/app/helpers/captain/chat_generation_recorder.rb
+++ b/enterprise/app/helpers/captain/chat_generation_recorder.rb
@@ -10,6 +10,7 @@ module Captain::ChatGenerationRecorder
# Create a generation span with model and token info for Langfuse cost calculation.
# Note: span duration will be near-zero since we create and end it immediately, but token counts are what Langfuse uses for cost calculation.
tracer.in_span("llm.captain.#{feature_name}.generation") do |span|
+ apply_current_langfuse_attributes(span)
set_generation_span_attributes(span, chat, message)
end
rescue StandardError => e
@@ -37,11 +38,23 @@ module Captain::ChatGenerationRecorder
ATTR_GEN_AI_USAGE_INPUT_TOKENS => message.input_tokens,
ATTR_GEN_AI_USAGE_OUTPUT_TOKENS => message.respond_to?(:output_tokens) ? message.output_tokens : nil,
ATTR_LANGFUSE_OBSERVATION_INPUT => format_input_messages(chat),
- ATTR_LANGFUSE_OBSERVATION_OUTPUT => message.respond_to?(:content) ? message.content.to_s : nil
+ ATTR_LANGFUSE_OBSERVATION_OUTPUT => message.respond_to?(:content) ? message.content.to_s : nil,
+ format(ATTR_LANGFUSE_OBSERVATION_METADATA, 'generation_stage') => generation_stage(message)
}
end
def format_input_messages(chat)
chat.messages[0...-1].map { |m| { role: m.role.to_s, content: m.content.to_s } }.to_json
end
+
+ def generation_stage(message)
+ message_has_tool_calls?(message) ? 'tool_call' : 'final_response'
+ end
+
+ def message_has_tool_calls?(message)
+ return false unless message.respond_to?(:tool_calls)
+
+ tool_calls = message.tool_calls
+ tool_calls.respond_to?(:any?) && tool_calls.any?
+ end
end
diff --git a/lib/captain/tool_instrumentation.rb b/lib/captain/tool_instrumentation.rb
index 157aab829..3c4a1c76e 100644
--- a/lib/captain/tool_instrumentation.rb
+++ b/lib/captain/tool_instrumentation.rb
@@ -10,12 +10,14 @@ module Captain::ToolInstrumentation
response = nil
executed = false
- tracer.in_span(params[:span_name]) do |span|
- set_tool_session_attributes(span, params)
- response = yield
- executed = true
- span.set_attribute(ATTR_LANGFUSE_OBSERVATION_OUTPUT, response[:message] || response.to_json)
- set_tool_session_error_attributes(span, response) if response.is_a?(Hash)
+ with_propagated_langfuse_attributes(params) do
+ tracer.in_span(params[:span_name]) do |span|
+ set_tool_session_attributes(span, params)
+ response = yield
+ executed = true
+ span.set_attribute(ATTR_LANGFUSE_OBSERVATION_OUTPUT, response[:message] || response.to_json)
+ set_tool_session_error_attributes(span, response) if response.is_a?(Hash)
+ end
end
response
rescue StandardError => e
@@ -24,9 +26,7 @@ module Captain::ToolInstrumentation
end
def set_tool_session_attributes(span, params)
- span.set_attribute(ATTR_LANGFUSE_USER_ID, params[:account_id].to_s) if params[:account_id]
- span.set_attribute(ATTR_LANGFUSE_SESSION_ID, "#{params[:account_id]}_#{params[:conversation_id]}") if params[:conversation_id].present?
- span.set_attribute(ATTR_LANGFUSE_TAGS, [params[:feature_name]].to_json)
+ set_metadata_attributes(span, params)
span.set_attribute(ATTR_LANGFUSE_OBSERVATION_INPUT, params[:messages].to_json)
end
@@ -43,6 +43,7 @@ module Captain::ToolInstrumentation
return unless message.respond_to?(:role) && message.role.to_s == 'assistant'
tracer.in_span("llm.#{event_name}.generation") do |span|
+ apply_current_langfuse_attributes(span)
span.set_attribute(ATTR_GEN_AI_PROVIDER, 'openai')
span.set_attribute(ATTR_GEN_AI_REQUEST_MODEL, model)
span.set_attribute(ATTR_GEN_AI_USAGE_INPUT_TOKENS, message.input_tokens)
diff --git a/lib/integrations/llm_instrumentation.rb b/lib/integrations/llm_instrumentation.rb
index 326bb901e..0257f5c3a 100644
--- a/lib/integrations/llm_instrumentation.rb
+++ b/lib/integrations/llm_instrumentation.rb
@@ -29,16 +29,18 @@ module Integrations::LlmInstrumentation
result = nil
executed = false
- tracer.in_span(params[:span_name]) do |span|
- set_metadata_attributes(span, params)
+ with_propagated_langfuse_attributes(params) do
+ tracer.in_span(params[:span_name]) do |span|
+ set_metadata_attributes(span, params)
- # By default, the input and output of a trace are set from the root observation
- span.set_attribute(ATTR_LANGFUSE_OBSERVATION_INPUT, params[:messages].to_json)
- result = yield
- executed = true
- span.set_attribute(ATTR_LANGFUSE_OBSERVATION_OUTPUT, result.to_json)
- set_error_attributes(span, result) if result.is_a?(Hash)
- result
+ # By default, the input and output of a trace are set from the root observation
+ span.set_attribute(ATTR_LANGFUSE_OBSERVATION_INPUT, params[:messages].to_json)
+ result = yield
+ executed = true
+ span.set_attribute(ATTR_LANGFUSE_OBSERVATION_OUTPUT, result.to_json)
+ set_error_attributes(span, result) if result.is_a?(Hash)
+ result
+ end
end
rescue StandardError => e
ChatwootExceptionTracker.new(e, account: resolve_account(params)).capture_exception
@@ -51,6 +53,7 @@ module Integrations::LlmInstrumentation
return yield unless ChatwootApp.otel_enabled?
tracer.in_span(format(TOOL_SPAN_NAME, tool_name)) do |span|
+ apply_current_langfuse_attributes(span)
span.set_attribute(ATTR_LANGFUSE_OBSERVATION_TYPE, 'tool')
span.set_attribute(ATTR_LANGFUSE_OBSERVATION_INPUT, arguments.to_json)
result = yield
@@ -96,23 +99,6 @@ module Integrations::LlmInstrumentation
end
end
- def instrument_with_span(span_name, params, &)
- result = nil
- executed = false
- tracer.in_span(span_name) do |span|
- track_result = lambda do |r|
- executed = true
- result = r
- end
- yield(span, track_result)
- end
- rescue StandardError => e
- ChatwootExceptionTracker.new(e, account: resolve_account(params)).capture_exception
- raise unless executed
-
- result
- end
-
private
def resolve_account(params)
diff --git a/lib/integrations/llm_instrumentation_completion_helpers.rb b/lib/integrations/llm_instrumentation_completion_helpers.rb
index 551d0780f..26af2aae1 100644
--- a/lib/integrations/llm_instrumentation_completion_helpers.rb
+++ b/lib/integrations/llm_instrumentation_completion_helpers.rb
@@ -10,7 +10,6 @@ module Integrations::LlmInstrumentationCompletionHelpers
span.set_attribute(ATTR_GEN_AI_REQUEST_MODEL, params[:model])
span.set_attribute('embedding.input_length', params[:input]&.length || 0)
span.set_attribute(ATTR_LANGFUSE_OBSERVATION_INPUT, params[:input].to_s)
- set_common_span_metadata(span, params)
end
def set_audio_transcription_span_attributes(span, params)
@@ -18,7 +17,6 @@ module Integrations::LlmInstrumentationCompletionHelpers
span.set_attribute(ATTR_GEN_AI_REQUEST_MODEL, params[:model] || 'whisper-1')
span.set_attribute('audio.duration_seconds', params[:duration]) if params[:duration]
span.set_attribute(ATTR_LANGFUSE_OBSERVATION_INPUT, params[:file_path].to_s) if params[:file_path]
- set_common_span_metadata(span, params)
end
def set_moderation_span_attributes(span, params)
@@ -26,12 +24,6 @@ module Integrations::LlmInstrumentationCompletionHelpers
span.set_attribute(ATTR_GEN_AI_REQUEST_MODEL, params[:model] || 'text-moderation-latest')
span.set_attribute('moderation.input_length', params[:input]&.length || 0)
span.set_attribute(ATTR_LANGFUSE_OBSERVATION_INPUT, params[:input].to_s)
- set_common_span_metadata(span, params)
- end
-
- def set_common_span_metadata(span, params)
- span.set_attribute(ATTR_LANGFUSE_USER_ID, params[:account_id].to_s) if params[:account_id]
- span.set_attribute(ATTR_LANGFUSE_TAGS, [params[:feature_name]].to_json) if params[:feature_name]
end
def set_embedding_result_attributes(span, result)
diff --git a/lib/integrations/llm_instrumentation_constants.rb b/lib/integrations/llm_instrumentation_constants.rb
index dfe1e7704..f274d1145 100644
--- a/lib/integrations/llm_instrumentation_constants.rb
+++ b/lib/integrations/llm_instrumentation_constants.rb
@@ -29,4 +29,5 @@ module Integrations::LlmInstrumentationConstants
ATTR_LANGFUSE_OBSERVATION_TYPE = 'langfuse.observation.type'
ATTR_LANGFUSE_OBSERVATION_INPUT = 'langfuse.observation.input'
ATTR_LANGFUSE_OBSERVATION_OUTPUT = 'langfuse.observation.output'
+ ATTR_LANGFUSE_OBSERVATION_METADATA = 'langfuse.observation.metadata.%s'
end
diff --git a/lib/integrations/llm_instrumentation_context.rb b/lib/integrations/llm_instrumentation_context.rb
new file mode 100644
index 000000000..27b1eb2b2
--- /dev/null
+++ b/lib/integrations/llm_instrumentation_context.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+module Integrations::LlmInstrumentationContext
+ LANGFUSE_ATTRIBUTES_KEY = :llm_instrumentation_langfuse_attributes
+ LANGFUSE_OBSERVATION_METADATA_KEY = :llm_instrumentation_langfuse_observation_metadata_attributes
+
+ private
+
+ def with_propagated_langfuse_attributes(params)
+ previous_attributes = current_langfuse_attributes
+ previous_observation_metadata_attributes = current_observation_metadata_attributes
+ self.current_langfuse_attributes = previous_attributes.merge(propagated_langfuse_attributes(params))
+ self.current_observation_metadata_attributes = previous_observation_metadata_attributes.merge(propagated_observation_metadata_attributes(params))
+
+ yield
+ ensure
+ self.current_langfuse_attributes = previous_attributes
+ self.current_observation_metadata_attributes = previous_observation_metadata_attributes
+ end
+
+ def apply_current_langfuse_attributes(span)
+ set_langfuse_attributes(span, current_langfuse_attributes)
+ set_langfuse_attributes(span, current_observation_metadata_attributes)
+ end
+
+ def current_langfuse_attributes
+ ActiveSupport::IsolatedExecutionState[LANGFUSE_ATTRIBUTES_KEY] || {}
+ end
+
+ def current_langfuse_attributes=(attrs)
+ ActiveSupport::IsolatedExecutionState[LANGFUSE_ATTRIBUTES_KEY] = attrs
+ end
+
+ def current_observation_metadata_attributes
+ ActiveSupport::IsolatedExecutionState[LANGFUSE_OBSERVATION_METADATA_KEY] || {}
+ end
+
+ def current_observation_metadata_attributes=(attrs)
+ ActiveSupport::IsolatedExecutionState[LANGFUSE_OBSERVATION_METADATA_KEY] = attrs
+ end
+end
diff --git a/lib/integrations/llm_instrumentation_helpers.rb b/lib/integrations/llm_instrumentation_helpers.rb
index 129092ed4..debbfaeda 100644
--- a/lib/integrations/llm_instrumentation_helpers.rb
+++ b/lib/integrations/llm_instrumentation_helpers.rb
@@ -2,6 +2,7 @@
module Integrations::LlmInstrumentationHelpers
include Integrations::LlmInstrumentationConstants
+ include Integrations::LlmInstrumentationContext
include Integrations::LlmInstrumentationCompletionHelpers
def determine_provider(model_name)
@@ -51,15 +52,55 @@ module Integrations::LlmInstrumentationHelpers
end
def set_metadata_attributes(span, params)
- session_id = params[:conversation_id].present? ? "#{params[:account_id]}_#{params[:conversation_id]}" : nil
- span.set_attribute(ATTR_LANGFUSE_USER_ID, params[:account_id].to_s) if params[:account_id]
- span.set_attribute(ATTR_LANGFUSE_SESSION_ID, session_id) if session_id.present?
- span.set_attribute(ATTR_LANGFUSE_TAGS, [params[:feature_name]].to_json)
+ set_langfuse_attributes(span, current_langfuse_attributes.merge(propagated_langfuse_attributes(params)))
+ set_langfuse_attributes(span, current_observation_metadata_attributes.merge(propagated_observation_metadata_attributes(params)))
+ end
- return unless params[:metadata].is_a?(Hash)
+ def propagated_langfuse_attributes(params)
+ attrs = {}
+ session_id = params[:conversation_id].present? ? "#{params[:account_id]}_#{params[:conversation_id]}" : nil
+
+ attrs[ATTR_LANGFUSE_USER_ID] = params[:account_id].to_s if params[:account_id]
+ attrs[ATTR_LANGFUSE_SESSION_ID] = session_id if session_id.present?
+ attrs[ATTR_LANGFUSE_TAGS] = [params[:feature_name].to_s] if params[:feature_name].present?
+
+ return attrs unless params[:metadata].is_a?(Hash)
params[:metadata].each do |key, value|
- span.set_attribute(format(ATTR_LANGFUSE_METADATA, key), value.to_s)
+ attrs[format(ATTR_LANGFUSE_METADATA, key)] = value.to_s
+ end
+
+ attrs
+ end
+
+ def propagated_observation_metadata_attributes(params)
+ attrs = {}
+ session_id = params[:conversation_id].present? ? "#{params[:account_id]}_#{params[:conversation_id]}" : nil
+
+ add_observation_metadata(attrs, 'user_id', params[:account_id])
+ add_observation_metadata(attrs, 'account_id', params[:account_id])
+ add_observation_metadata(attrs, 'session_id', session_id)
+ add_observation_metadata(attrs, 'trace_tags', [params[:feature_name]].to_json)
+ add_observation_metadata(attrs, 'feature_name', params[:feature_name])
+
+ return attrs unless params[:metadata].is_a?(Hash)
+
+ params[:metadata].each do |key, value|
+ add_observation_metadata(attrs, key, value)
+ end
+
+ attrs
+ end
+
+ def add_observation_metadata(attrs, key, value)
+ return if value.blank?
+
+ attrs[format(ATTR_LANGFUSE_OBSERVATION_METADATA, key)] = value.to_s
+ end
+
+ def set_langfuse_attributes(span, attrs)
+ attrs.each do |key, value|
+ span.set_attribute(key, value)
end
end
end
diff --git a/lib/integrations/llm_instrumentation_spans.rb b/lib/integrations/llm_instrumentation_spans.rb
index 85ea599f8..2def9749d 100644
--- a/lib/integrations/llm_instrumentation_spans.rb
+++ b/lib/integrations/llm_instrumentation_spans.rb
@@ -39,6 +39,7 @@ module Integrations::LlmInstrumentationSpans
tool_name = tool_call.name.to_s
span = tracer.start_span(format(TOOL_SPAN_NAME, tool_name))
+ apply_current_langfuse_attributes(span)
span.set_attribute(ATTR_LANGFUSE_OBSERVATION_TYPE, 'tool')
span.set_attribute(ATTR_LANGFUSE_OBSERVATION_INPUT, tool_call.arguments.to_json)
@@ -61,6 +62,24 @@ module Integrations::LlmInstrumentationSpans
Rails.logger.warn "Failed to end tool span: #{e.message}"
end
+ def instrument_with_span(span_name, params, &)
+ result = nil
+ executed = false
+ tracer.in_span(span_name) do |span|
+ set_metadata_attributes(span, params)
+ track_result = lambda do |r|
+ executed = true
+ result = r
+ end
+ yield(span, track_result)
+ end
+ rescue StandardError => e
+ ChatwootExceptionTracker.new(e, account: resolve_account(params)).capture_exception
+ raise unless executed
+
+ result
+ end
+
private
def set_llm_turn_request_attributes(span, params)
diff --git a/lib/opentelemetry_config.rb b/lib/opentelemetry_config.rb
index 5ed17e098..32be413d0 100644
--- a/lib/opentelemetry_config.rb
+++ b/lib/opentelemetry_config.rb
@@ -72,7 +72,10 @@ module OpentelemetryConfig
config = {
endpoint: traces_endpoint,
- headers: { 'Authorization' => "Basic #{auth_header}" }
+ headers: {
+ 'Authorization' => "Basic #{auth_header}",
+ 'x-langfuse-ingestion-version' => '4'
+ }
}
config[:ssl_verify_mode] = OpenSSL::SSL::VERIFY_NONE if Rails.env.development?
diff --git a/spec/enterprise/services/captain/llm/assistant_chat_service_spec.rb b/spec/enterprise/services/captain/llm/assistant_chat_service_spec.rb
index 9d233943e..6b2cc55c8 100644
--- a/spec/enterprise/services/captain/llm/assistant_chat_service_spec.rb
+++ b/spec/enterprise/services/captain/llm/assistant_chat_service_spec.rb
@@ -39,6 +39,30 @@ RSpec.describe Captain::Llm::AssistantChatService do
allow(mock_chat).to receive(:ask).and_return(mock_response)
service.generate_response(message_history: [{ role: 'user', content: 'Hello' }])
end
+
+ it 'marks final response generations for observation-level evaluators' do
+ service = described_class.new(assistant: assistant, conversation: conversation)
+ message = instance_double(RubyLLM::Message, content: 'Final answer', input_tokens: 10, output_tokens: 20, tool_calls: {})
+
+ attributes = service.send(:generation_attributes, mock_chat, message)
+
+ expect(attributes['langfuse.observation.metadata.generation_stage']).to eq('final_response')
+ end
+
+ it 'marks tool call generations separately from final responses' do
+ service = described_class.new(assistant: assistant, conversation: conversation)
+ message = instance_double(
+ RubyLLM::Message,
+ content: '',
+ input_tokens: 10,
+ output_tokens: 20,
+ tool_calls: { 'call_1' => instance_double(RubyLLM::ToolCall) }
+ )
+
+ attributes = service.send(:generation_attributes, mock_chat, message)
+
+ expect(attributes['langfuse.observation.metadata.generation_stage']).to eq('tool_call')
+ end
end
describe 'image analysis' do
diff --git a/spec/lib/integrations/llm_instrumentation_spec.rb b/spec/lib/integrations/llm_instrumentation_spec.rb
index 0be62f437..f291cd7b2 100644
--- a/spec/lib/integrations/llm_instrumentation_spec.rb
+++ b/spec/lib/integrations/llm_instrumentation_spec.rb
@@ -144,7 +144,10 @@ RSpec.describe Integrations::LlmInstrumentation do
expect(mock_span).to have_received(:set_attribute).with('langfuse.user.id', '123')
expect(mock_span).to have_received(:set_attribute).with('langfuse.session.id', '123_456')
- expect(mock_span).to have_received(:set_attribute).with('langfuse.trace.tags', '["reply_suggestion"]')
+ expect(mock_span).to have_received(:set_attribute).with('langfuse.trace.tags', ['reply_suggestion'])
+ expect(mock_span).to have_received(:set_attribute).with('langfuse.observation.metadata.user_id', '123')
+ expect(mock_span).to have_received(:set_attribute).with('langfuse.observation.metadata.session_id', '123_456')
+ expect(mock_span).to have_received(:set_attribute).with('langfuse.observation.metadata.feature_name', 'reply_suggestion')
end
it 'sets completion message attributes when result contains message' do
@@ -253,6 +256,76 @@ RSpec.describe Integrations::LlmInstrumentation do
expect(mock_span).to have_received(:set_attribute).with('langfuse.observation.output', result_data.to_json)
end
+ it 'propagates trace attributes as observation metadata to child tool spans' do
+ root_span = instance_double(OpenTelemetry::Trace::Span)
+ tool_span = instance_double(OpenTelemetry::Trace::Span)
+ tool_instance = test_class.new
+ allow(root_span).to receive(:set_attribute)
+ allow(tool_span).to receive(:set_attribute)
+ allow(instance).to receive(:tracer).and_return(mock_tracer)
+ allow(tool_instance).to receive(:tracer).and_return(mock_tracer)
+ allow(mock_tracer).to receive(:in_span).with('llm.test').and_yield(root_span)
+ allow(mock_tracer).to receive(:in_span).with('tool.search').and_yield(tool_span)
+
+ instance.instrument_agent_session(params) do
+ tool_instance.instrument_tool_call('search', { query: 'test' }) { 'tool result' }
+ end
+
+ expect(tool_span).to have_received(:set_attribute).with('langfuse.observation.metadata.user_id', '123')
+ expect(tool_span).to have_received(:set_attribute).with('langfuse.observation.metadata.session_id', '123_456')
+ expect(tool_span).to have_received(:set_attribute).with('langfuse.observation.metadata.feature_name', 'reply_suggestion')
+ end
+
+ it 'keeps inherited session metadata for nested service spans with their own feature tag' do
+ root_span = instance_double(OpenTelemetry::Trace::Span)
+ nested_span = instance_double(OpenTelemetry::Trace::Span)
+ nested_instance = test_class.new
+ nested_params = params.merge(span_name: 'llm.translate_query', conversation_id: nil, feature_name: 'translate_query')
+ allow(root_span).to receive(:set_attribute)
+ allow(nested_span).to receive(:set_attribute)
+ allow(instance).to receive(:tracer).and_return(mock_tracer)
+ allow(nested_instance).to receive(:tracer).and_return(mock_tracer)
+ allow(mock_tracer).to receive(:in_span).with('llm.test').and_yield(root_span)
+ allow(mock_tracer).to receive(:in_span).with('llm.translate_query').and_yield(nested_span)
+
+ instance.instrument_agent_session(params) do
+ nested_instance.instrument_llm_call(nested_params) { 'translated query' }
+ end
+
+ expect(nested_span).to have_received(:set_attribute).with('langfuse.session.id', '123_456')
+ expect(nested_span).to have_received(:set_attribute).with('langfuse.trace.tags', ['translate_query'])
+ expect(nested_span).to have_received(:set_attribute).with('langfuse.observation.metadata.session_id', '123_456')
+ expect(nested_span).to have_received(:set_attribute).with('langfuse.observation.metadata.feature_name', 'translate_query')
+ end
+
+ it 'propagates session metadata to nested embedding spans' do
+ root_span = instance_double(OpenTelemetry::Trace::Span)
+ embedding_span = instance_double(OpenTelemetry::Trace::Span)
+ embedding_instance = test_class.new
+ embedding_params = {
+ span_name: 'llm.captain.embedding',
+ account_id: 123,
+ feature_name: 'embedding',
+ model: 'text-embedding-3-small',
+ input: 'search result'
+ }
+ allow(root_span).to receive(:set_attribute)
+ allow(embedding_span).to receive(:set_attribute)
+ allow(instance).to receive(:tracer).and_return(mock_tracer)
+ allow(embedding_instance).to receive(:tracer).and_return(mock_tracer)
+ allow(mock_tracer).to receive(:in_span).with('llm.test').and_yield(root_span)
+ allow(mock_tracer).to receive(:in_span).with('llm.captain.embedding').and_yield(embedding_span)
+
+ instance.instrument_agent_session(params) do
+ embedding_instance.instrument_embedding_call(embedding_params) { [0.1, 0.2, 0.3] }
+ end
+
+ expect(embedding_span).to have_received(:set_attribute).with('langfuse.session.id', '123_456')
+ expect(embedding_span).to have_received(:set_attribute).with('langfuse.trace.tags', ['embedding'])
+ expect(embedding_span).to have_received(:set_attribute).with('langfuse.observation.metadata.session_id', '123_456')
+ expect(embedding_span).to have_received(:set_attribute).with('langfuse.observation.metadata.feature_name', 'embedding')
+ end
+
# Regression test for Langfuse double-counting bug.
# Setting gen_ai.request.model on parent spans causes Langfuse to classify them as
# GENERATIONs instead of SPANs, resulting in cost being counted multiple times