fix: address PR review comments

- P2: Make regex more robust by allowing optional leading whitespace in definition line parsing
- P3: Add test coverage for readFileTool truncation path

Changes:
- Updated regex in truncateDefinitions.ts to handle indented output or CRLF artifacts
- Added tests for whitespace handling in truncateDefinitions.spec.ts
- Added comprehensive tests for readFileTool truncation behavior in readFileTool.spec.ts

Author: daniel-lxs

src/core/tools/__tests__/readFileTool.spec.ts

@@ -414,6 +414,61 @@ describe("read_file tool with maxReadFileLine setting", () => {
 			expect(result).toContain(`<list_code_definition_names>`)
 			expect(result).toContain("<notice>Showing only 3 of 5 total lines")
 		})
+
+		it("should truncate code definitions when file exceeds maxReadFileLine", async () => {
+			// Setup - file with 100 lines but we'll only read first 30
+			const content = "Line 1\nLine 2\nLine 3"
+			const numberedContent = "1 | Line 1\n2 | Line 2\n3 | Line 3"
+			const fullDefinitions = `# file.txt
+10--20 | function foo() {
+50--60 | function bar() {
+80--90 | function baz() {`
+			const truncatedDefinitions = `# file.txt
+10--20 | function foo() {`
+
+			mockedReadLines.mockResolvedValue(content)
+			mockedParseSourceCodeDefinitionsForFile.mockResolvedValue(fullDefinitions)
+			addLineNumbersMock.mockReturnValue(numberedContent)
+
+			// Execute with maxReadFileLine = 30
+			const result = await executeReadFileTool({}, { maxReadFileLine: 30, totalLines: 100 })
+
+			// Verify that only definitions within the first 30 lines are included
+			expect(result).toContain(`<file><path>${testFilePath}</path>`)
+			expect(result).toContain(`<content lines="1-30">`)
+			expect(result).toContain(`<list_code_definition_names>`)
+
+			// Should include foo (starts at line 10) but not bar (starts at line 50) or baz (starts at line 80)
+			expect(result).toContain("10--20 | function foo()")
+			expect(result).not.toContain("50--60 | function bar()")
+			expect(result).not.toContain("80--90 | function baz()")
+
+			expect(result).toContain("<notice>Showing only 30 of 100 total lines")
+		})
+
+		it("should handle truncation when all definitions are beyond the line limit", async () => {
+			// Setup - all definitions start after maxReadFileLine
+			const content = "Line 1\nLine 2\nLine 3"
+			const numberedContent = "1 | Line 1\n2 | Line 2\n3 | Line 3"
+			const fullDefinitions = `# file.txt
+50--60 | function foo() {
+80--90 | function bar() {`
+
+			mockedReadLines.mockResolvedValue(content)
+			mockedParseSourceCodeDefinitionsForFile.mockResolvedValue(fullDefinitions)
+			addLineNumbersMock.mockReturnValue(numberedContent)
+
+			// Execute with maxReadFileLine = 30
+			const result = await executeReadFileTool({}, { maxReadFileLine: 30, totalLines: 100 })
+
+			// Verify that only the header is included (all definitions filtered out)
+			expect(result).toContain(`<file><path>${testFilePath}</path>`)
+			expect(result).toContain(`<content lines="1-30">`)
+			expect(result).toContain(`<list_code_definition_names>`)
+			expect(result).toContain("# file.txt")
+			expect(result).not.toContain("50--60 | function foo()")
+			expect(result).not.toContain("80--90 | function bar()")
+		})
 	})
 
 	describe("when maxReadFileLine equals or exceeds file length", () => {

src/core/tools/helpers/__tests__/truncateDefinitions.spec.ts

@@ -130,4 +130,31 @@ describe("truncateDefinitionsToLineLimit", () => {
 
 		expect(result).toBe(expected)
 	})
+
+	it("should handle definitions with leading whitespace", () => {
+		const definitions = `# test.ts
+	 10--20 | function foo() {
+	 30--40 | function bar() {
+	 50--60 | function baz() {`
+
+		const result = truncateDefinitionsToLineLimit(definitions, 25)
+		const expected = `# test.ts
+	 10--20 | function foo() {`
+
+		expect(result).toBe(expected)
+	})
+
+	it("should handle definitions with mixed whitespace patterns", () => {
+		const definitions = `# test.ts
+10--20 | function foo() {
+	 30--40 | function bar() {
+	50--60 | function baz() {`
+
+		const result = truncateDefinitionsToLineLimit(definitions, 35)
+		const expected = `# test.ts
+10--20 | function foo() {
+	 30--40 | function bar() {`
+
+		expect(result).toBe(expected)
+	})
 })

src/core/tools/helpers/truncateDefinitions.ts

@@ -25,7 +25,8 @@ export function truncateDefinitionsToLineLimit(definitions: string, maxReadFileL
 		const line = lines[i]
 
 		// Match definition format: "startLine--endLine | content" or "lineNumber | content"
-		const rangeMatch = line.match(/^(\d+)(?:--(\d+))?\s*\|/)
+		// Allow optional leading whitespace to handle indented output or CRLF artifacts
+		const rangeMatch = line.match(/^\s*(\d+)(?:--(\d+))?\s*\|/)
 
 		if (rangeMatch) {
 			const startLine = parseInt(rangeMatch[1], 10)