diff --git a/.changeset/devtools-instrumentation-line-numbers.md b/.changeset/devtools-instrumentation-line-numbers.md
new file mode 100644
index 00000000000..92ffca6735a
--- /dev/null
+++ b/.changeset/devtools-instrumentation-line-numbers.md
@@ -0,0 +1,6 @@
+---
+'@qwik.dev/devtools': patch
+'@qwik.dev/mcp': patch
+---
+
+fix: click-to-source opens the right line when devtools or mcp is enabled
diff --git a/packages/devtools/kit/src/rpc-core.ts b/packages/devtools/kit/src/rpc-core.ts
index b3f2e18cdcf..188b8b0af19 100644
--- a/packages/devtools/kit/src/rpc-core.ts
+++ b/packages/devtools/kit/src/rpc-core.ts
@@ -1,10 +1,10 @@
 import SuperJSON from 'superjson';
-import { createBirpc, type EventOptions } from 'birpc';
+import { createBirpc, type BirpcResolver } from 'birpc';
 
 interface RpcChannel {
   post: (serialized: string) => void;
   on: (handler: (serialized: string) => void) => void;
-  resolver?: EventOptions['resolver'];
+  resolver?: BirpcResolver<unknown>;
 }
 
 const RPC_TIMEOUT = 120_000;
diff --git a/packages/devtools/plugin/src/parse/__snapshots__/parse.unit.ts.snap b/packages/devtools/plugin/src/parse/__snapshots__/parse.unit.ts.snap
index 01c5846cda5..cf3de966fd3 100644
--- a/packages/devtools/plugin/src/parse/__snapshots__/parse.unit.ts.snap
+++ b/packages/devtools/plugin/src/parse/__snapshots__/parse.unit.ts.snap
@@ -38,8 +38,7 @@ interface ButtonProps {
   testValue: Signal<string>;
 }
 
-export default component$<ButtonProps>((props) => {
-  const collecthook = useCollectHooks("/abs/path/Button.tsx_default")
+export default component$<ButtonProps>((props) => { const collecthook = useCollectHooks("/abs/path/Button.tsx_default");
   const { class: className = '', onClick$ } = props;
   const testValue2 = props.testValue
   console.log('testValue', testValue2)
@@ -48,97 +47,27 @@ export default component$<ButtonProps>((props) => {
     dd:12,
     cc: 33,
     aa: [1,2,3  ]
-  });
-  collecthook({
-    variableName: 'store',
-    hookType: 'useStore',
-    category: 'VariableDeclarator',
-    data: store
-  });
-
-  const signal = useSignal<any>('111');
-  collecthook({
-    variableName: 'signal',
-    hookType: 'useSignal',
-    category: 'VariableDeclarator',
-    data: signal
-  });
-
-  const constantValue = useConstant(() => 'CONST');
-  collecthook({
-    variableName: 'constantValue',
-    hookType: 'useConstant',
-    category: 'VariableDeclarator',
-    data: constantValue
-  });
-
-  const serverData = useServerData<any>('demo-key');
-  collecthook({
-    variableName: 'serverData',
-    hookType: 'useServerData',
-    category: 'VariableDeclarator',
-    data: serverData
-  });
-
-  const location = useLocation();
-  collecthook({
-    variableName: 'location',
-    hookType: 'useLocation',
-    category: 'VariableDeclarator',
-    data: location
-  });
-
-  const navigate = useNavigate();
-  collecthook({
-    variableName: 'navigate',
-    hookType: 'useNavigate',
-    category: 'VariableDeclarator',
-    data: navigate
-  });
-
-  const content = useContent();
-  collecthook({
-    variableName: 'content',
-    hookType: 'useContent',
-    category: 'VariableDeclarator',
-    data: content
-  });
-
-  const head = useDocumentHead();
-  collecthook({
-    variableName: 'head',
-    hookType: 'useDocumentHead',
-    category: 'VariableDeclarator',
-    data: head
-  });
-
+  }); collecthook({ variableName: 'store', hookType: 'useStore', category: 'VariableDeclarator', data: store });
+  const signal = useSignal<any>('111'); collecthook({ variableName: 'signal', hookType: 'useSignal', category: 'VariableDeclarator', data: signal });
+  const constantValue = useConstant(() => 'CONST'); collecthook({ variableName: 'constantValue', hookType: 'useConstant', category: 'VariableDeclarator', data: constantValue });
+  const serverData = useServerData<any>('demo-key'); collecthook({ variableName: 'serverData', hookType: 'useServerData', category: 'VariableDeclarator', data: serverData });
+  const location = useLocation(); collecthook({ variableName: 'location', hookType: 'useLocation', category: 'VariableDeclarator', data: location });
+  const navigate = useNavigate(); collecthook({ variableName: 'navigate', hookType: 'useNavigate', category: 'VariableDeclarator', data: navigate });
+  const content = useContent(); collecthook({ variableName: 'content', hookType: 'useContent', category: 'VariableDeclarator', data: content });
+  const head = useDocumentHead(); collecthook({ variableName: 'head', hookType: 'useDocumentHead', category: 'VariableDeclarator', data: head });
 
   
 
   useTask$(({ track }) => {
     track(() => store.count);
     signal.value = '33333'
-  })
-  collecthook({
-    variableName: 'useTask',
-    hookType: 'useTask',
-    category: 'expressionStatement',
-    data: undefined
-  });
-
+  }); collecthook({ variableName: 'useTask', hookType: 'useTask', category: 'expressionStatement', data: undefined });
 
   // eslint-disable-next-line qwik/no-use-visible-task
   useVisibleTask$(({ track }) => {
     track(() => store.count);
     signal.value = '2227'
-  })
-  collecthook({
-    variableName: 'useVisibleTask',
-    hookType: 'useVisibleTask',
-    category: 'expressionStatement',
-    data: undefined
-  });
-
+  }); collecthook({ variableName: 'useVisibleTask', hookType: 'useVisibleTask', category: 'expressionStatement', data: undefined });
 
   const qwikContainer = useComputed$(() => {
     try {
@@ -151,102 +80,32 @@ export default component$<ButtonProps>((props) => {
       console.error(error);
       return null;
     }
-  });
-  collecthook({
-    variableName: 'qwikContainer',
-    hookType: 'useComputed',
-    category: 'VariableDeclarator',
-    data: qwikContainer
-  });
-
+  }); collecthook({ variableName: 'qwikContainer', hookType: 'useComputed', category: 'VariableDeclarator', data: qwikContainer });
 
   const asyncComputedValue =  useAsyncComputed$(({ track }) =>
     Promise.resolve(track(signal) + 3),
-  );
-  collecthook({
-    variableName: 'asyncComputedValue',
-    hookType: 'useAsyncComputed',
-    category: 'VariableDeclarator',
-    data: asyncComputedValue
-  });
-
+  ); collecthook({ variableName: 'asyncComputedValue', hookType: 'useAsyncComputed', category: 'VariableDeclarator', data: asyncComputedValue });
                                                                                                                                       
   useContextProvider(ButtonContext, {
     theme: 'primary',
     size: 'large'
-  });
-  collecthook({
-    variableName: 'useContextProvider',
-    hookType: 'useContextProvider',
-    category: 'expressionStatement',
-    data: undefined
-  });
-
-    let _customhook_0 = useHooks('Button');
-  collecthook({
-    variableName: '_customhook_0',
-    hookType: 'customhook',
-    category: 'VariableDeclarator',
-    data: _customhook_0
-  });
-
-  const context = useContext(ButtonContext);
-  collecthook({
-    variableName: 'context',
-    hookType: 'useContext',
-    category: 'VariableDeclarator',
-    data: context
-  });
-
-
-  const buttonId = useId();
-  collecthook({
-    variableName: 'buttonId',
-    hookType: 'useId',
-    category: 'VariableDeclarator',
-    data: buttonId
-  });
+  }); collecthook({ variableName: 'useContextProvider', hookType: 'useContextProvider', category: 'expressionStatement', data: undefined });
+  let _customhook_0 = useHooks('Button'); collecthook({ variableName: '_customhook_0', hookType: 'customhook', category: 'VariableDeclarator', data: _customhook_0 });
+  const context = useContext(ButtonContext); collecthook({ variableName: 'context', hookType: 'useContext', category: 'VariableDeclarator', data: context });
 
+  const buttonId = useId(); collecthook({ variableName: 'buttonId', hookType: 'useId', category: 'VariableDeclarator', data: buttonId });
 
   useOnDocument('keydown', $(() => {
     console.log('Document keydown event');
-  }));
-  collecthook({
-    variableName: 'useOnDocument',
-    hookType: 'useOnDocument',
-    category: 'expressionStatement',
-    data: undefined
-  });
-
-  const dd = useHooks('Button1')
-  collecthook({
-    variableName: 'dd',
-    hookType: 'customhook',
-    category: 'VariableDeclarator',
-    data: dd
-  });
-
+  })); collecthook({ variableName: 'useOnDocument', hookType: 'useOnDocument', category: 'expressionStatement', data: undefined });
+  const dd = useHooks('Button1'); collecthook({ variableName: 'dd', hookType: 'customhook', category: 'VariableDeclarator', data: dd });
   useOnWindow('resize', $(() => {
     console.log('Window resized');
-  }));
-  collecthook({
-    variableName: 'useOnWindow',
-    hookType: 'useOnWindow',
-    category: 'expressionStatement',
-    data: undefined
-  });
-
+  })); collecthook({ variableName: 'useOnWindow', hookType: 'useOnWindow', category: 'expressionStatement', data: undefined });
 
   useOn('click', $(() => {
     console.log('Host clicked');
-  }));
-  collecthook({
-    variableName: 'useOn',
-    hookType: 'useOn',
-    category: 'expressionStatement',
-    data: undefined
-  });
-
+  })); collecthook({ variableName: 'useOn', hookType: 'useOn', category: 'expressionStatement', data: undefined });
 
   const resourceData = useResource$(async ({ track }) => {
     track(() => store.count);
@@ -255,14 +114,7 @@ export default component$<ButtonProps>((props) => {
       message: \`Resource data for count: \${store.count}\`,
       timestamp: Date.now()
     };
-  });
-  collecthook({
-    variableName: 'resourceData',
-    hookType: 'useResource',
-    category: 'VariableDeclarator',
-    data: resourceData
-  });
-
+  }); collecthook({ variableName: 'resourceData', hookType: 'useResource', category: 'VariableDeclarator', data: resourceData });
 
   const customSerialized = useSerializer$(() => ({
     deserialize: () => ({ n: store.count }),
@@ -270,14 +122,7 @@ export default component$<ButtonProps>((props) => {
       current.n = store.count;
       return current;
     }
-  }));
-  collecthook({
-    variableName: 'customSerialized',
-    hookType: 'useSerializer',
-    category: 'VariableDeclarator',
-    data: customSerialized
-  });
-
+  })); collecthook({ variableName: 'customSerialized', hookType: 'useSerializer', category: 'VariableDeclarator', data: customSerialized });
 
   useStyles$(\`
     .custom-button {
@@ -292,14 +137,7 @@ export default component$<ButtonProps>((props) => {
     .custom-button:hover {
       transform: scale(1.05);
     }
-  \`);
-  collecthook({
-    variableName: 'useStyles',
-    hookType: 'useStyles',
-    category: 'expressionStatement',
-    data: undefined
-  });
-
+  \`); collecthook({ variableName: 'useStyles', hookType: 'useStyles', category: 'expressionStatement', data: undefined });
 
   useStylesScoped$(\`
     .scoped-button {
@@ -310,27 +148,13 @@ export default component$<ButtonProps>((props) => {
       border-radius: 3px;
       cursor: pointer;
     }
-  \`);
-  collecthook({
-    variableName: 'useStylesScoped',
-    hookType: 'useStylesScoped',
-    category: 'expressionStatement',
-    data: undefined
-  });
-
+  \`); collecthook({ variableName: 'useStylesScoped', hookType: 'useStylesScoped', category: 'expressionStatement', data: undefined });
   const debounce = useDebouncer(
     $((value: string) => {
       signal.value = value;
     }),
     1000
-  );
-  collecthook({
-    variableName: 'debounce',
-    hookType: 'customhook',
-    category: 'VariableDeclarator',
-    data: debounce
-  });
-
+  ); collecthook({ variableName: 'debounce', hookType: 'customhook', category: 'VariableDeclarator', data: debounce });
  
 
   const handleClick = $(async () => {
diff --git a/packages/devtools/plugin/src/parse/helpers.ts b/packages/devtools/plugin/src/parse/helpers.ts
index 19f98b12099..d5478236352 100644
--- a/packages/devtools/plugin/src/parse/helpers.ts
+++ b/packages/devtools/plugin/src/parse/helpers.ts
@@ -77,36 +77,9 @@ export function isCustomHook(hookName: string): boolean {
 }
 
 // ============================================================================
-// Code Position Utilities
+// Statement Utilities
 // ============================================================================
 
-/** Finds the start position of the line containing the given index */
-export function findLineStart(code: string, index: number): number {
-  for (let i = index - 1; i >= 0; i--) {
-    const ch = code[i];
-    if (ch === '\n' || ch === '\r') {
-      return i + 1;
-    }
-  }
-  return 0;
-}
-
-/** Reads the indentation (spaces/tabs) starting from a given position */
-export function readIndent(code: string, indexFrom: number): string {
-  let indent = '';
-  let i = indexFrom;
-  while (i < code.length) {
-    const ch = code[i];
-    if (ch === ' ' || ch === '\t') {
-      indent += ch;
-      i++;
-    } else {
-      break;
-    }
-  }
-  return indent;
-}
-
 /** Removes trailing semicolon and whitespace from a code segment */
 export function trimStatementSemicolon(segment: string): string {
   return segment.trim().replace(/;?\s*$/, '');
@@ -118,21 +91,14 @@ export function trimStatementSemicolon(segment: string): string {
 
 export type CollecthookCategory = 'VariableDeclarator' | 'expressionStatement';
 
-/** Builds the collecthook() call code with proper indentation */
+/** Builds a single-line collecthook() call so injected tracking never adds source lines */
 export function buildCollecthookPayload(
-  indent: string,
   variableName: string,
   hookType: string,
   category: CollecthookCategory,
   hookExpression: string | 'undefined'
 ): string {
-  const dataValue = hookExpression === 'undefined' ? 'undefined' : hookExpression;
-  return `${indent}collecthook({
-${indent}  variableName: '${variableName}',
-${indent}  hookType: '${hookType}',
-${indent}  category: '${category}',
-${indent}  data: ${dataValue}
-${indent}});\n`;
+  return `collecthook({ variableName: '${variableName}', hookType: '${hookType}', category: '${category}', data: ${hookExpression} });`;
 }
 
 /** Checks if a collecthook call already exists after the given position (by variable ID) */
diff --git a/packages/devtools/plugin/src/parse/hookTracker.ts b/packages/devtools/plugin/src/parse/hookTracker.ts
index 54164f3183c..f82ff47d112 100644
--- a/packages/devtools/plugin/src/parse/hookTracker.ts
+++ b/packages/devtools/plugin/src/parse/hookTracker.ts
@@ -10,8 +10,6 @@ import {
   getVariableIdentifierName,
   isKnownHook,
   normalizeQrlHookName,
-  findLineStart,
-  readIndent,
   buildCollecthookPayload,
   hasCollecthookAfterByVariableId,
   hasCollecthookAfterByVariableName,
@@ -19,7 +17,7 @@ import {
   isCustomHook,
 } from './helpers';
 import { INNER_USE_HOOK } from '@qwik.dev/devtools/kit';
-import type { InjectionTask } from './types';
+import type { InjectionTask, InsertTask } from './types';
 import { applySourceEdits } from './sourceEdits';
 
 // ============================================================================
@@ -86,7 +84,7 @@ function processVariableDeclarator(
     return null;
   }
 
-  const { declEnd, indent } = getPositionInfo(code, range);
+  const [, declEnd] = range;
 
   // Custom hook
   if (isCustomHook(normalizedName)) {
@@ -94,13 +92,12 @@ function processVariableDeclarator(
       return null;
     }
     const payload = buildCollecthookPayload(
-      indent,
       variableId,
       'customhook',
       'VariableDeclarator',
       variableId
     );
-    return { kind: 'insert', pos: declEnd, text: '\n' + payload };
+    return insertAfterStatement(code, declEnd, payload);
   }
 
   // Known hook
@@ -112,13 +109,12 @@ function processVariableDeclarator(
   }
 
   const payload = buildCollecthookPayload(
-    indent,
     variableId,
     normalizedName,
     'VariableDeclarator',
     variableId
   );
-  return { kind: 'insert', pos: declEnd, text: '\n' + payload };
+  return insertAfterStatement(code, declEnd, payload);
 }
 
 // ============================================================================
@@ -147,8 +143,6 @@ function processExpressionStatement(
   }
 
   const [stmtStart, stmtEnd] = stmtRange;
-  const lineStart = findLineStart(code, stmtStart);
-  const indent = readIndent(code, lineStart);
 
   // Known hook (expression form)
   if (isKnownHook(normalizedName)) {
@@ -156,21 +150,20 @@ function processExpressionStatement(
       return null;
     }
     const payload = buildCollecthookPayload(
-      indent,
       normalizedName,
       normalizedName,
       'expressionStatement',
       'undefined'
     );
     return {
-      task: { kind: 'insert', pos: stmtEnd, text: '\n' + payload },
+      task: insertAfterStatement(code, stmtEnd, payload),
       newIndex: currentIndex,
     };
   }
 
   // Custom hook (expression form) - convert to variable declaration
   if (isCustomHook(normalizedName)) {
-    return convertToVariableDeclaration(code, stmtStart, stmtEnd, indent, currentIndex);
+    return convertToVariableDeclaration(code, stmtStart, stmtEnd, currentIndex);
   }
 
   return null;
@@ -181,14 +174,11 @@ function convertToVariableDeclaration(
   code: string,
   stmtStart: number,
   stmtEnd: number,
-  indent: string,
   currentIndex: number
 ): { task: InjectionTask; newIndex: number } {
   const callSource = code.slice(stmtStart, stmtEnd);
   const variableName = `_customhook_${currentIndex}`;
-  const declLine = `${indent}let ${variableName} = ${trimStatementSemicolon(callSource)};\n`;
   const payload = buildCollecthookPayload(
-    indent,
     variableName,
     'customhook',
     'VariableDeclarator',
@@ -200,7 +190,7 @@ function convertToVariableDeclaration(
       kind: 'replace',
       start: stmtStart,
       end: stmtEnd,
-      text: declLine + payload,
+      text: `let ${variableName} = ${trimStatementSemicolon(callSource)}; ${payload}`,
     },
     newIndex: currentIndex + 1,
   };
@@ -255,6 +245,12 @@ function extractHookCall(node: unknown): { hookName: string; normalizedName: str
 // Position Helpers
 // ============================================================================
 
+/** Inserts on the statement's own line, adding the `;` it may lack because of ASI */
+function insertAfterStatement(code: string, statementEnd: number, statement: string): InsertTask {
+  const separator = code[statementEnd - 1] === ';' ? ' ' : '; ';
+  return { kind: 'insert', pos: statementEnd, text: separator + statement };
+}
+
 function getParentRange(parent: any): [number, number] | null {
   const range = parent?.range as number[] | undefined;
   if (!range) {
@@ -262,13 +258,3 @@ function getParentRange(parent: any): [number, number] | null {
   }
   return [range[0], range[1]];
 }
-
-function getPositionInfo(
-  code: string,
-  range: [number, number]
-): { declStart: number; declEnd: number; indent: string } {
-  const [declStart, declEnd] = range;
-  const lineStart = findLineStart(code, declStart);
-  const indent = readIndent(code, lineStart);
-  return { declStart, declEnd, indent };
-}
diff --git a/packages/devtools/plugin/src/parse/initInjector.ts b/packages/devtools/plugin/src/parse/initInjector.ts
index cf9212be44b..e1558080f1a 100644
--- a/packages/devtools/plugin/src/parse/initInjector.ts
+++ b/packages/devtools/plugin/src/parse/initInjector.ts
@@ -4,7 +4,6 @@
  */
 
 import type { ComponentBodyRange } from './componentBodies';
-import { readIndent } from './helpers';
 import { INNER_USE_HOOK } from '@qwik.dev/devtools/kit';
 import type { InjectOptions, InsertTask } from './types';
 import { applySourceEdits } from './sourceEdits';
@@ -48,15 +47,11 @@ function createInitTask(
     return null;
   }
 
-  // Calculate insertion position
-  const { insertIndex, prefixNewline } = calculateInsertPosition(code, insertPos);
-  const indent = readIndent(code, insertIndex);
-
-  // Build initialization code
+  // Stay on the body's opening line so source line numbers don't shift.
   const componentArg = buildComponentArg(options?.path, exportName);
-  const initLine = `${prefixNewline}${indent}const collecthook = ${INNER_USE_HOOK}(${componentArg})\n`;
+  const initStatement = ` const collecthook = ${INNER_USE_HOOK}(${componentArg});`;
 
-  return { kind: 'insert', pos: insertIndex, text: initLine };
+  return { kind: 'insert', pos: insertPos, text: initStatement };
 }
 
 // ============================================================================
@@ -68,22 +63,6 @@ function hasExistingCollecthook(code: string, insertPos: number): boolean {
   return /const\s+collecthook\s*=\s*useCollectHooks\s*\(/.test(lookahead);
 }
 
-function calculateInsertPosition(
-  code: string,
-  insertPos: number
-): {
-  insertIndex: number;
-  prefixNewline: string;
-} {
-  if (code[insertPos] === '\r' && code[insertPos + 1] === '\n') {
-    return { insertIndex: insertPos + 2, prefixNewline: '' };
-  }
-  if (code[insertPos] === '\n') {
-    return { insertIndex: insertPos + 1, prefixNewline: '' };
-  }
-  return { insertIndex: insertPos, prefixNewline: '\n' };
-}
-
 // ============================================================================
 // Code Builders
 // ============================================================================
diff --git a/packages/devtools/plugin/src/parse/parse.unit.ts b/packages/devtools/plugin/src/parse/parse.unit.ts
index 28992fbb3a7..ffc8b703f55 100644
--- a/packages/devtools/plugin/src/parse/parse.unit.ts
+++ b/packages/devtools/plugin/src/parse/parse.unit.ts
@@ -232,7 +232,7 @@ describe('injectCollectHooks', () => {
     );
   });
 
-  it('inserts initialization at the very beginning of component$ body with proper indent', () => {
+  it('inserts initialization at the very beginning of component$ body, on its opening line', () => {
     const input = sampleVarDecl;
     const output = parseQwikCode(input, { path: '/abs/path/Button.tsx?id=abc' });
     const initLine = 'const collecthook = useCollectHooks("/abs/path/Button.tsx_default")';
@@ -242,8 +242,7 @@ describe('injectCollectHooks', () => {
     expect(initIdx).toBeGreaterThan(-1);
     expect(firstStmtIdx).toBeGreaterThan(-1);
     expect(initIdx).toBeLessThan(firstStmtIdx);
-    const initLineWithIndent = '\n  ' + initLine;
-    expect(output).toContain(initLineWithIndent);
+    expect(output).toContain(`{ ${initLine};`);
   });
 
   it('is idempotent: running twice does not duplicate init', () => {
@@ -335,9 +334,7 @@ export default component$(function(props){
     const output = parseQwikCode(src, { path: 'CUSTOM_PATH' });
     // import is handled by plugin layer; parseQwikCode only injects init and payloads
     expect(
-      /component\$\(function\([^)]*\)\s*\{[\r\n]+\s*const collecthook = useCollectHooks\(/m.test(
-        output
-      )
+      /component\$\(function\([^)]*\)\s*\{ const collecthook = useCollectHooks\(/m.test(output)
     ).toBe(true);
     const decl = 'const signal = useSignal(0);';
     const declIdx = output.indexOf(decl);
@@ -356,8 +353,9 @@ export default component$(function(props){
     const afterDecl = output.slice(declIdx);
     const match = afterDecl.match(hookBlock);
     expect(match).not.toBeNull();
-    expect(output).toContain('\n  collecthook({');
-    expect(output).toContain('\n    data: signal');
+    expect(output).toContain(
+      "const signal = useSignal<any>('111'); collecthook({ variableName: 'signal',"
+    );
   });
 
   it('injects for custom use*-not-in-list (e.g. useDebouncer)', () => {
diff --git a/packages/devtools/plugin/src/plugin/devtools.ts b/packages/devtools/plugin/src/plugin/devtools.ts
index 7edd2f62369..db5751867f6 100644
--- a/packages/devtools/plugin/src/plugin/devtools.ts
+++ b/packages/devtools/plugin/src/plugin/devtools.ts
@@ -46,6 +46,7 @@ export function devtoolsPlugin(opts: QwikDevtoolsOptions = {}): Plugin {
       }
     },
 
+    // Runs before the optimizer, which has no input sourcemap: never add or remove source lines.
     transform: {
       order: 'pre',
       handler(code, id) {
diff --git a/packages/devtools/plugin/src/transforms/root-transform.ts b/packages/devtools/plugin/src/transforms/root-transform.ts
index 564bcf1dcb1..1dc329ee109 100644
--- a/packages/devtools/plugin/src/transforms/root-transform.ts
+++ b/packages/devtools/plugin/src/transforms/root-transform.ts
@@ -1,7 +1,7 @@
 import { normalizeExcludePathnames } from '../../../kit/src/overlay-paths';
-import { readIndent } from '../parse/helpers';
 import { applySourceEdits } from '../parse/sourceEdits';
 import { parseProgram, traverseProgram } from '../parse/traverse';
+import { prependImportIfMissing } from './source-utils';
 
 export interface QwikDevtoolsOptions {
   overlay?: {
@@ -14,34 +14,22 @@ const STYLES_IMPORT = `import '@qwik.dev/devtools/ui/styles.css';`;
 
 export function transformRootFile(code: string, opts: QwikDevtoolsOptions = {}): string {
   const excludePathnames = normalizeExcludePathnames(opts.overlay?.excludePathnames);
-  const bodyInsertion = findBodyInsertion(code);
-  if (bodyInsertion !== null) {
+  const bodyClosingStart = findBodyClosingStart(code);
+  if (bodyClosingStart !== null) {
     const devtoolsElement =
       excludePathnames.length > 0
         ? `<QwikDevtools excludePathnames={${JSON.stringify(excludePathnames)}} />`
         : '<QwikDevtools />';
     code = applySourceEdits(code, [
-      {
-        kind: 'insert',
-        pos: bodyInsertion.pos,
-        text: `${bodyInsertion.prefix}${devtoolsElement}${bodyInsertion.suffix}`,
-      },
+      { kind: 'insert', pos: bodyClosingStart, text: devtoolsElement },
     ]);
   }
 
-  if (!code.includes(DEVTOOLS_IMPORT)) {
-    code = `${DEVTOOLS_IMPORT}\n${code}`;
-  }
-
-  if (!code.includes(STYLES_IMPORT)) {
-    code = `${STYLES_IMPORT}\n${code}`;
-  }
-
-  return code;
+  return prependImportIfMissing(prependImportIfMissing(code, DEVTOOLS_IMPORT), STYLES_IMPORT);
 }
 
-function findBodyInsertion(code: string): { pos: number; prefix: string; suffix: string } | null {
-  const edits: BodyInsertionEdit[] = [];
+function findBodyClosingStart(code: string): number | null {
+  let closingStart: number | null = null;
 
   try {
     const program = parseProgram(code);
@@ -52,15 +40,7 @@ function findBodyInsertion(code: string): { pos: number; prefix: string; suffix:
           return;
         }
 
-        const closingStart = node.closingElement.start;
-        const lineStart = findLineStart(code, closingStart);
-        const closingIndent = readIndent(code, lineStart);
-        const hasOnlyIndentBeforeClosing = code.slice(lineStart, closingStart).trim() === '';
-        edits.push({
-          pos: hasOnlyIndentBeforeClosing ? lineStart : closingStart,
-          prefix: hasOnlyIndentBeforeClosing ? `${closingIndent}  ` : `\n${closingIndent}  `,
-          suffix: hasOnlyIndentBeforeClosing ? '\n' : '',
-        });
+        closingStart = node.closingElement.start;
         path.stop();
       },
     });
@@ -68,18 +48,7 @@ function findBodyInsertion(code: string): { pos: number; prefix: string; suffix:
     return null;
   }
 
-  const edit = edits[0];
-  return edit ?? null;
-}
-
-function findLineStart(code: string, index: number): number {
-  for (let i = index - 1; i >= 0; i--) {
-    const ch = code[i];
-    if (ch === '\n' || ch === '\r') {
-      return i + 1;
-    }
-  }
-  return 0;
+  return closingStart;
 }
 
 function getJsxName(name: unknown): string | undefined {
@@ -98,9 +67,3 @@ interface JsxElementNode {
     start: number;
   };
 }
-
-interface BodyInsertionEdit {
-  pos: number;
-  prefix: string;
-  suffix: string;
-}
diff --git a/packages/devtools/plugin/src/transforms/source-utils.ts b/packages/devtools/plugin/src/transforms/source-utils.ts
index 7540d05baa5..6a2626a9325 100644
--- a/packages/devtools/plugin/src/transforms/source-utils.ts
+++ b/packages/devtools/plugin/src/transforms/source-utils.ts
@@ -1,6 +1,11 @@
+/** Prepends on line 1 so the optimizer still sees every source line where it was */
+export function prependImportIfMissing(code: string, importStatement: string): string {
+  return code.includes(importStatement) ? code : `${importStatement}${code}`;
+}
+
 export function injectNamedImportIfMissing(code: string, key: string, name: string): string {
   if (code.includes(key)) {
     return code;
   }
-  return `import { ${name} } from '${key}';\n${code}`;
+  return prependImportIfMissing(code, `import { ${name} } from '${key}';`);
 }
diff --git a/packages/devtools/plugin/src/transforms/transforms.unit.ts b/packages/devtools/plugin/src/transforms/transforms.unit.ts
index 01c6ec0f8d8..73a6d6793ac 100644
--- a/packages/devtools/plugin/src/transforms/transforms.unit.ts
+++ b/packages/devtools/plugin/src/transforms/transforms.unit.ts
@@ -1,4 +1,5 @@
 import { describe, expect, test } from 'vitest';
+import { parseSync } from 'oxc-parser';
 import { transformComponentFile } from './component-transform';
 import { rewriteComponentQrlImport } from './perf-transform';
 import { transformRootFile } from './root-transform';
@@ -27,6 +28,17 @@ export default component$(() => {
 });
 `;
 
+// Source locations (data-qwik-inspector, QRL dev spans) are computed after these transforms.
+function expectSameSourceLines(source: string, transformed: string) {
+  const sourceLines = source.split('\n');
+  const transformedLines = transformed.split('\n');
+  expect(parseSync('file.tsx', transformed, { lang: 'tsx' }).errors).toEqual([]);
+  expect(transformedLines).toHaveLength(sourceLines.length);
+  sourceLines.forEach((line, index) => {
+    expect(transformedLines[index]).toContain(line.trim());
+  });
+}
+
 describe('transform facades', () => {
   test('component transform injects useCollectHooks import and collecthook init', () => {
     const transformed = transformComponentFile(
@@ -74,7 +86,42 @@ export default component$(() => {
     const transformed = transformRootFile(source);
 
     expect(transformed).toContain("const fakeHtml = '<body><main>String body</main></body>';");
-    expect(transformed).toContain('<main>Real body</main>\n        <QwikDevtools />');
+    expect(transformed).toContain('<main>Real body</main>\n      <QwikDevtools /></body>');
+  });
+
+  test('component transform keeps every source line on its original line number', () => {
+    const source = `import { component$, useSignal, useStore, useTask$ } from '@qwik.dev/core';
+import { useCounter, useLogger } from './hooks';
+
+export const Counter = component$(() => {
+  const count = useSignal(0)
+  const state = useStore({ items: [] });
+  const local = useCounter();
+  useLogger();
+  useTask$(({ track }) => {
+    track(() => count.value);
+  });
+  return (
+    <button onClick$={() => count.value++}>
+      {count.value} {state.items.length} {local}
+    </button>
+  );
+});
+
+export default component$(() => <Counter />);
+`;
+
+    const transformed = transformComponentFile(source, '/repo/src/components/counter.tsx');
+
+    expect(transformed).toContain('collecthook(');
+    expectSameSourceLines(source, transformed);
+  });
+
+  test('root transform keeps every source line on its original line number', () => {
+    const transformed = transformRootFile(ROOT_SOURCE);
+
+    expect(transformed).toContain('<QwikDevtools />');
+    expectSameSourceLines(ROOT_SOURCE, transformed);
   });
 
   test('perf transform rewrites componentQrl import', () => {
diff --git a/packages/mcp/src/index.ts b/packages/mcp/src/index.ts
index c95f2851b6e..c3f5f672e6b 100644
--- a/packages/mcp/src/index.ts
+++ b/packages/mcp/src/index.ts
@@ -132,6 +132,7 @@ export function qwikMcp(): Plugin {
         );
       }
     },
+    // Runs before the optimizer, which has no input sourcemap: never add or remove source lines.
     transform(code, id) {
       if (
         /\.[jt]sx(?:\?|$)/.test(id) &&
diff --git a/packages/mcp/src/integration.test.ts b/packages/mcp/src/integration.test.ts
index c7a62384acf..e59787380af 100644
--- a/packages/mcp/src/integration.test.ts
+++ b/packages/mcp/src/integration.test.ts
@@ -175,6 +175,12 @@ for (const mode of ['csr', 'ssr']) {
       expect(await page.locator('script[src*="virtual:qwik-mcp"]').count()).toBe(1);
       await page.locator('#counter').waitFor();
       expect(pageErrors).toEqual([]);
+      if (mode === 'ssr') {
+        // Hook instrumentation must not shift the source lines the optimizer reports.
+        expect(await page.locator('#counter').getAttribute('data-qwik-inspector')).toMatch(
+          /\/routes\/index\.tsx:5:5$/
+        );
+      }
       await expect
         .poll(async () => (await call('inspect_page')).structuredContent?.tree)
         .toEqual(expect.arrayContaining([expect.objectContaining({ id: expect.any(String) })]));