feat: Improve tool call extraction and stripping to support multiple …

pkg/providers/claude_cli_provider.go

@@ -185,21 +185,6 @@ func (p *ClaudeCliProvider) stripToolCallsJSON(text string) string {
 	return stripToolCallsFromText(text)
 }
 
-// findMatchingBrace finds the index after the closing brace matching the opening brace at pos.
-func findMatchingBrace(text string, pos int) int {
-	depth := 0
-	for i := pos; i < len(text); i++ {
-		if text[i] == '{' {
-			depth++
-		} else if text[i] == '}' {
-			depth--
-			if depth == 0 {
-				return i + 1
-			}
-		}
-	}
-	return pos
-}
 
 // claudeCliJSONResponse represents the JSON output from the claude CLI.
 // Matches the real claude CLI v2.x output format.

pkg/providers/claude_cli_provider_test.go

@@ -964,26 +964,3 @@ func TestStripToolCallsJSON_OnlyToolCalls(t *testing.T) {
 	}
 }
 
-// --- findMatchingBrace tests ---
-
-func TestFindMatchingBrace(t *testing.T) {
-	tests := []struct {
-		text string
-		pos  int
-		want int
-	}{
-		{`{"a":1}`, 0, 7},
-		{`{"a":{"b":2}}`, 0, 13},
-		{`text {"a":1} more`, 5, 12},
-		{`{unclosed`, 0, 0},      // no match returns pos
-		{`{}`, 0, 2},             // empty object
-		{`{{{}}}`, 0, 6},         // deeply nested
-		{`{"a":"b{c}d"}`, 0, 13}, // braces in strings (simplified matcher)
-	}
-	for _, tt := range tests {
-		got := findMatchingBrace(tt.text, tt.pos)
-		if got != tt.want {
-			t.Errorf("findMatchingBrace(%q, %d) = %d, want %d", tt.text, tt.pos, got, tt.want)
-		}
-	}
-}

pkg/providers/tool_call_extract.go

@@ -5,68 +5,176 @@ import (
 	"strings"
 )
 
-// extractToolCallsFromText parses tool call JSON from response text.
+// extractToolCallsFromText parses multiple tool call JSON blocks from response text.
 // Both ClaudeCliProvider and CodexCliProvider use this to extract
 // tool calls that the model outputs in its response text.
 func extractToolCallsFromText(text string) []ToolCall {
-	start := strings.Index(text, `{"tool_calls"`)
-	if start == -1 {
-		return nil
-	}
+	var result []ToolCall
+	pos := 0
 
-	end := findMatchingBrace(text, start)
-	if end == start {
-		return nil
-	}
+	for {
+		_, _, jsonStart, jsonEnd, found := nextToolCallBlock(text, pos)
+		if !found {
+			break
+		}
 
-	jsonStr := text[start:end]
-
-	var wrapper struct {
-		ToolCalls []struct {
-			ID       string `json:"id"`
-			Type     string `json:"type"`
-			Function struct {
-				Name      string `json:"name"`
-				Arguments string `json:"arguments"`
-			} `json:"function"`
-		} `json:"tool_calls"`
-	}
+		jsonStr := text[jsonStart:jsonEnd]
+		pos = jsonEnd
 
-	if err := json.Unmarshal([]byte(jsonStr), &wrapper); err != nil {
-		return nil
-	}
+		var wrapper struct {
+			ToolCalls []struct {
+				ID       string `json:"id"`
+				Type     string `json:"type"`
+				Function struct {
+					Name      string `json:"name"`
+					Arguments string `json:"arguments"`
+				} `json:"function"`
+			} `json:"tool_calls"`
+		}
 
-	var result []ToolCall
-	for _, tc := range wrapper.ToolCalls {
-		var args map[string]any
-		json.Unmarshal([]byte(tc.Function.Arguments), &args)
-
-		result = append(result, ToolCall{
-			ID:        tc.ID,
-			Type:      tc.Type,
-			Name:      tc.Function.Name,
-			Arguments: args,
-			Function: &FunctionCall{
+		if err := json.Unmarshal([]byte(jsonStr), &wrapper); err != nil {
+			continue
+		}
+
+		for _, tc := range wrapper.ToolCalls {
+			var args map[string]any
+			_ = json.Unmarshal([]byte(tc.Function.Arguments), &args)
+
+			result = append(result, ToolCall{
+				ID:        tc.ID,
+				Type:      tc.Type,
 				Name:      tc.Function.Name,
-				Arguments: tc.Function.Arguments,
-			},
-		})
+				Arguments: args,
+				Function: &FunctionCall{
+					Name:      tc.Function.Name,
+					Arguments: tc.Function.Arguments,
+				},
+			})
+		}
 	}
 
 	return result
 }
 
-// stripToolCallsFromText removes tool call JSON from response text.
+// stripToolCallsFromText removes all tool call JSON blocks (and their markdown wrappers) from response text.
 func stripToolCallsFromText(text string) string {
-	start := strings.Index(text, `{"tool_calls"`)
-	if start == -1 {
-		return text
+	res := text
+	pos := 0
+	for {
+		blockStart, blockEnd, _, _, found := nextToolCallBlock(res, pos)
+		if !found {
+			break
+		}
+
+		// Remove the block and ensure exactly one double newline if it was in the middle of text
+		prefix := strings.TrimRight(res[:blockStart], " \t\n\r")
+		suffix := strings.TrimLeft(res[blockEnd:], " \t\n\r")
+
+		if prefix == "" {
+			res = suffix
+		} else if suffix == "" {
+			res = prefix
+		} else {
+			res = prefix + "\n\n" + suffix
+		}
+		pos = len(prefix)
 	}
+	return strings.TrimSpace(res)
+}
+
+// nextToolCallBlock finds the next tool_calls JSON block (and its markdown wrapper) in text starting from startFrom.
+func nextToolCallBlock(text string, startFrom int) (blockStart, blockEnd, jsonStart, jsonEnd int, found bool) {
+	idx := startFrom
+	for {
+		if idx >= len(text) {
+			return 0, 0, 0, 0, false
+		}
+
+		// Find the start of a potential JSON object starting with "tool_calls"
+		openingBrace := strings.Index(text[idx:], "{")
+		if openingBrace == -1 {
+			return 0, 0, 0, 0, false
+		}
+		jsonStart = idx + openingBrace
+
+		// Check if it contains "tool_calls" after the brace
+		afterBrace := text[jsonStart+1:]
+		trimmed := strings.TrimLeft(afterBrace, " \t\n\r")
+		if strings.HasPrefix(trimmed, `"tool_calls"`) {
+			jsonEnd = findMatchingBrace(text, jsonStart)
+			if jsonEnd != jsonStart {
+				// Found a valid block
+				break
+			}
+		}
 
-	end := findMatchingBrace(text, start)
-	if end == start {
-		return text
+		// Not a tool call block or no matching brace, continue search after this brace
+		idx = jsonStart + 1
 	}
 
-	return strings.TrimSpace(text[:start] + text[end:])
+	blockStart = jsonStart
+	blockEnd = jsonEnd
+
+	// Check for markdown code block wrapper
+	// Look back for ```json or ``` ignoring intermediate whitespace/newlines
+	prefix := text[:jsonStart]
+	trimmedPrefix := strings.TrimRight(prefix, " \t\n\r")
+	if strings.HasSuffix(trimmedPrefix, "```json") {
+		blockStart = strings.LastIndex(trimmedPrefix, "```json")
+	} else if strings.HasSuffix(trimmedPrefix, "```") {
+		blockStart = strings.LastIndex(trimmedPrefix, "```")
+	}
+
+	// Look ahead for ``` ignoring intermediate whitespace/newlines
+	suffix := text[jsonEnd:]
+	trimmedSuffix := strings.TrimLeft(suffix, " \t\n\r")
+	if strings.HasPrefix(trimmedSuffix, "```") {
+		// blockEnd should include the opening whitespace of suffix + the 3 ticks
+		wsLen := len(suffix) - len(trimmedSuffix)
+		blockEnd = jsonEnd + wsLen + 3
+	}
+
+	return blockStart, blockEnd, jsonStart, jsonEnd, true
 }
+
+// findMatchingBrace finds the index after the closing brace matching the opening brace at pos.
+// It accounts for braces inside strings and escaped characters.
+func findMatchingBrace(text string, pos int) int {
+	if pos < 0 || pos >= len(text) || text[pos] != '{' {
+		return pos
+	}
+
+	depth := 0
+	inString := false
+	escaped := false
+
+	for i := pos; i < len(text); i++ {
+		char := text[i]
+
+		if inString {
+			if escaped {
+				escaped = false
+			} else if char == '\\' {
+				escaped = true
+			} else if char == '"' {
+				inString = false
+			}
+			continue
+		}
+
+		if char == '"' {
+			inString = true
+			continue
+		}
+
+		if char == '{' {
+			depth++
+		} else if char == '}' {
+			depth--
+			if depth == 0 {
+				return i + 1
+			}
+		}
+	}
+	return pos
+}