grafana · alexander-akhmetov · Apr 5, 2026
diff --git a/dotnet/src/Grafana.Sigil/SigilClient.cs b/dotnet/src/Grafana.Sigil/SigilClient.cs
@@ -54,6 +54,7 @@ public sealed class SigilClient : IAsyncDisposable
     internal const string SpanAttrToolDescription = "gen_ai.tool.description";
     internal const string SpanAttrToolCallArguments = "gen_ai.tool.call.arguments";
     internal const string SpanAttrToolCallResult = "gen_ai.tool.call.result";
+    internal const string SpanAttrToolCallCount = "sigil.gen_ai.tool_call_count";
     private const int MaxRatingConversationIdLen = 255;
     private const int MaxRatingIdLen = 128;
     private const int MaxRatingGenerationIdLen = 255;
@@ -1187,6 +1188,12 @@ internal static void ApplyGenerationSpanAttributes(Activity activity, Generation
         {
             activity.SetTag(SpanAttrReasoningTokens, generation.Usage.ReasoningTokens);
         }
+
+        var toolCallCount = CountToolCallParts(generation.Output);
+        if (toolCallCount != 0)
+        {
+            activity.SetTag(SpanAttrToolCallCount, toolCallCount);
+        }
     }
 
     internal static void ApplyEmbeddingStartSpanAttributes(Activity activity, EmbeddingStart start)

diff --git a/dotnet/tests/Grafana.Sigil.Tests/ConformanceTests.cs b/dotnet/tests/Grafana.Sigil.Tests/ConformanceTests.cs
@@ -149,6 +149,7 @@ public async Task SyncRoundtripSemantics()
         Assert.Equal("generateText", span.GetTagItem("gen_ai.operation.name")?.ToString());
         Assert.Equal("Roundtrip conversation", span.GetTagItem("sigil.conversation.title")?.ToString());
         Assert.Equal("user-roundtrip", span.GetTagItem("user.id")?.ToString());
+        Assert.Equal(1L, span.GetTagItem("sigil.gen_ai.tool_call_count"));
         Assert.Contains("gen_ai.client.operation.duration", env.MetricNames);
         Assert.Contains("gen_ai.client.token.usage", env.MetricNames);
         Assert.DoesNotContain("gen_ai.client.time_to_first_token", env.MetricNames);

diff --git a/go/sigil/client.go b/go/sigil/client.go
@@ -139,6 +139,7 @@ const (
 	spanAttrToolDescription        = "gen_ai.tool.description"
 	spanAttrToolCallArguments      = "gen_ai.tool.call.arguments"
 	spanAttrToolCallResult         = "gen_ai.tool.call.result"
+	spanAttrToolCallCount          = "sigil.gen_ai.tool_call_count"
 
 	metricOperationDuration      = "gen_ai.client.operation.duration"
 	metricTokenUsage             = "gen_ai.client.token.usage"
@@ -1262,6 +1263,10 @@ func generationSpanAttributes(g Generation) []attribute.KeyValue {
 		attrs = append(attrs, attribute.Int64(spanAttrReasoningTokens, g.Usage.ReasoningTokens))
 	}
 
+	if count := countToolCalls(g.Output); count != 0 {
+		attrs = append(attrs, attribute.Int64(spanAttrToolCallCount, int64(count)))
+	}
+
 	return attrs
 }
 

diff --git a/go/sigil/conformance_helpers_test.go b/go/sigil/conformance_helpers_test.go
@@ -68,6 +68,7 @@ const (
 	spanAttrCacheWriteTokens       = "gen_ai.usage.cache_write_input_tokens"
 	spanAttrCacheCreationTokens    = "gen_ai.usage.cache_creation_input_tokens"
 	spanAttrReasoningTokens        = "gen_ai.usage.reasoning_tokens"
+	spanAttrToolCallCount          = "sigil.gen_ai.tool_call_count"
 	metricOperationDuration        = "gen_ai.client.operation.duration"
 	metricTokenUsage               = "gen_ai.client.token.usage"
 	metricTimeToFirstToken         = "gen_ai.client.time_to_first_token"

diff --git a/go/sigil/conformance_test.go b/go/sigil/conformance_test.go
@@ -204,6 +204,7 @@ func TestConformance_FullGenerationRoundtrip(t *testing.T) {
 	requireSpanInt64Attr(t, attrs, spanAttrCacheWriteTokens, 4)
 	requireSpanInt64Attr(t, attrs, spanAttrCacheCreationTokens, 6)
 	requireSpanInt64Attr(t, attrs, spanAttrReasoningTokens, 9)
+	requireSpanInt64Attr(t, attrs, spanAttrToolCallCount, 1)
 
 	duration := findHistogram[float64](t, metrics, metricOperationDuration)
 	durationPoint := findHistogramPoint(t, duration, map[string]string{

diff --git a/java/core/src/main/java/com/grafana/sigil/sdk/SigilClient.java b/java/core/src/main/java/com/grafana/sigil/sdk/SigilClient.java
@@ -76,6 +76,7 @@ public final class SigilClient implements AutoCloseable {
     static final String SPAN_ATTR_TOOL_DESCRIPTION = "gen_ai.tool.description";
     static final String SPAN_ATTR_TOOL_CALL_ARGUMENTS = "gen_ai.tool.call.arguments";
     static final String SPAN_ATTR_TOOL_CALL_RESULT = "gen_ai.tool.call.result";
+    static final String SPAN_ATTR_TOOL_CALL_COUNT = "sigil.gen_ai.tool_call_count";
     private static final int MAX_RATING_CONVERSATION_ID_LEN = 255;
     private static final int MAX_RATING_ID_LEN = 128;
     private static final int MAX_RATING_GENERATION_ID_LEN = 255;
@@ -1028,6 +1029,11 @@ static void setGenerationSpanAttributes(Span span, Generation generation) {
             span.setAttribute(SPAN_ATTR_CACHE_CREATION_TOKENS, usage.getCacheCreationInputTokens());
             span.setAttribute(SPAN_ATTR_REASONING_TOKENS, usage.getReasoningTokens());
         }
+
+        long toolCallCount = countToolCalls(generation.getOutput());
+        if (toolCallCount != 0) {
+            span.setAttribute(SPAN_ATTR_TOOL_CALL_COUNT, toolCallCount);
+        }
     }
 
     static void setToolSpanAttributes(Span span, ToolExecutionStart seed) {

diff --git a/java/core/src/test/java/com/grafana/sigil/sdk/ConformanceTest.java b/java/core/src/test/java/com/grafana/sigil/sdk/ConformanceTest.java
@@ -147,6 +147,8 @@ void syncRoundtripSemantics() throws Exception {
                     .isEqualTo("Roundtrip conversation");
             assertThat(span.getAttributes().get(AttributeKey.stringKey(SigilClient.SPAN_ATTR_USER_ID)))
                     .isEqualTo("user-roundtrip");
+            assertThat(span.getAttributes().get(AttributeKey.longKey(SigilClient.SPAN_ATTR_TOOL_CALL_COUNT)))
+                    .isEqualTo(1L);
             assertThat(metricNames).contains(SigilClient.METRIC_OPERATION_DURATION, SigilClient.METRIC_TOKEN_USAGE);
             assertThat(metricNames).doesNotContain(SigilClient.METRIC_TTFT);
         }

diff --git a/js/src/client.ts b/js/src/client.ts
@@ -105,6 +105,7 @@ const spanAttrToolType = 'gen_ai.tool.type';
 const spanAttrToolDescription = 'gen_ai.tool.description';
 const spanAttrToolCallArguments = 'gen_ai.tool.call.arguments';
 const spanAttrToolCallResult = 'gen_ai.tool.call.result';
+const spanAttrToolCallCount = 'sigil.gen_ai.tool_call_count';
 const maxRatingConversationIdLen = 255;
 const maxRatingIdLen = 128;
 const maxRatingGenerationIdLen = 255;
@@ -1222,6 +1223,7 @@ function setGenerationSpanAttributes(
     responseId?: string;
     responseModel?: string;
     stopReason?: string;
+    output?: Message[];
     usage?: {
       inputTokens?: number;
       outputTokens?: number;
@@ -1320,6 +1322,11 @@ function setGenerationSpanAttributes(
     span.setAttribute(spanAttrFinishReasons, [generation.stopReason]);
   }
 
+  const toolCallCount = countToolCallParts(generation.output ?? []);
+  if (toolCallCount !== 0) {
+    span.setAttribute(spanAttrToolCallCount, toolCallCount);
+  }
+
   const usage = generation.usage;
   if (usage === undefined) {
     return;

diff --git a/js/test/conformance.test.mjs b/js/test/conformance.test.mjs
@@ -138,6 +138,7 @@ test('conformance sync roundtrip semantics', async () => {
     assert.equal(span.attributes['gen_ai.operation.name'], 'generateText');
     assert.equal(span.attributes['sigil.conversation.title'], 'Roundtrip conversation');
     assert.equal(span.attributes['user.id'], 'user-roundtrip');
+    assert.equal(span.attributes['sigil.gen_ai.tool_call_count'], 1);
     assert.ok(metricNames.includes('gen_ai.client.operation.duration'));
     assert.ok(metricNames.includes('gen_ai.client.token.usage'));
     assert.ok(!metricNames.includes('gen_ai.client.time_to_first_token'));

diff --git a/python/sigil_sdk/client.py b/python/sigil_sdk/client.py
@@ -101,6 +101,7 @@
 _span_attr_tool_description = "gen_ai.tool.description"
 _span_attr_tool_call_arguments = "gen_ai.tool.call.arguments"
 _span_attr_tool_call_result = "gen_ai.tool.call.result"
+_span_attr_tool_call_count = "sigil.gen_ai.tool_call_count"
 _max_rating_conversation_id_len = 255
 _max_rating_id_len = 128
 _max_rating_generation_id_len = 255
@@ -1243,6 +1244,10 @@ def _set_generation_span_attributes(span: Span, generation: Generation) -> None:
     if usage.reasoning_tokens:
         span.set_attribute(_span_attr_reasoning_tokens, usage.reasoning_tokens)
 
+    tool_call_count = _count_tool_call_parts(generation.output)
+    if tool_call_count:
+        span.set_attribute(_span_attr_tool_call_count, tool_call_count)
+
 
 def _set_embedding_start_span_attributes(span: Span, start: EmbeddingStart) -> None:
     span.set_attribute(_span_attr_operation_name, _default_embedding_operation_name)

diff --git a/python/tests/test_conformance.py b/python/tests/test_conformance.py
@@ -324,6 +324,7 @@ def test_conformance_sync_roundtrip_semantics() -> None:
         assert span.attributes["gen_ai.operation.name"] == "generateText"
         assert span.attributes[_span_attr_conversation_title] == "Roundtrip conversation"
         assert span.attributes[_span_attr_user_id] == "user-roundtrip"
+        assert span.attributes["sigil.gen_ai.tool_call_count"] == 1
         assert "gen_ai.client.operation.duration" in metrics
         assert "gen_ai.client.token.usage" in metrics
         assert "gen_ai.client.time_to_first_token" not in metrics