Merge pull request #2161 from ksylvan/anthropic-max-tokens-fix

fix: respect Anthropic chat option max token overrides

cmd/generate_changelog/incoming/2161.txt

@@ -0,0 +1,11 @@
+### PR [#2161](https://github.com/danielmiessler/Fabric/pull/2161) by [ksylvan](https://github.com/ksylvan): fix: respect Anthropic chat option max token overrides
+
+- Fix: respect Anthropic chat option max token overrides
+
+- Use configured Anthropic max tokens as default
+- Apply chat option max tokens when provided
+
+- Preserve existing behavior for missing token overrides
+- Add tests for default max token selection
+
+- Add tests for explicit max token overrides

internal/plugins/ai/anthropic/anthropic.go

@@ -233,9 +233,14 @@ func (an *Client) SendStream(
 func (an *Client) buildMessageParams(msgs []anthropic.MessageParam, opts *domain.ChatOptions) (
 	params anthropic.MessageNewParams) {
 
+	maxTokens := an.maxTokens
+	if opts.MaxTokens > 0 {
+		maxTokens = opts.MaxTokens
+	}
+
 	params = anthropic.MessageNewParams{
 		Model:     anthropic.Model(opts.Model),
-		MaxTokens: int64(an.maxTokens),
+		MaxTokens: int64(maxTokens),
 		Messages:  msgs,
 	}
 

internal/plugins/ai/anthropic/anthropic_test.go

@@ -99,6 +99,43 @@ func TestBuildMessageParams_WithoutSearch(t *testing.T) {
 	}
 }
 
+func TestBuildMessageParams_UsesConfiguredMaxTokensByDefault(t *testing.T) {
+	client := NewClient()
+	opts := &domain.ChatOptions{
+		Model:       "claude-3-5-sonnet-latest",
+		Temperature: domain.DefaultTemperature,
+		TopP:        domain.DefaultTopP,
+	}
+	messages := []anthropic.MessageParam{
+		anthropic.NewUserMessage(anthropic.NewTextBlock("Hello")),
+	}
+
+	params := client.buildMessageParams(messages, opts)
+
+	if params.MaxTokens != int64(client.maxTokens) {
+		t.Errorf("Expected default max_tokens %d, got %d", client.maxTokens, params.MaxTokens)
+	}
+}
+
+func TestBuildMessageParams_UsesChatOptionsMaxTokens(t *testing.T) {
+	client := NewClient()
+	opts := &domain.ChatOptions{
+		Model:       "claude-3-5-sonnet-latest",
+		Temperature: domain.DefaultTemperature,
+		TopP:        domain.DefaultTopP,
+		MaxTokens:   8192,
+	}
+	messages := []anthropic.MessageParam{
+		anthropic.NewUserMessage(anthropic.NewTextBlock("Hello")),
+	}
+
+	params := client.buildMessageParams(messages, opts)
+
+	if params.MaxTokens != int64(opts.MaxTokens) {
+		t.Errorf("Expected max_tokens %d, got %d", opts.MaxTokens, params.MaxTokens)
+	}
+}
+
 func TestBuildMessageParams_WithSearch(t *testing.T) {
 	client := NewClient()
 	opts := &domain.ChatOptions{