diff --git a/package-lock.json b/package-lock.json
index 840d188..c68bf42 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -8,6 +8,9 @@
       "name": "taskbound",
       "version": "0.2.3",
       "license": "MIT",
+      "dependencies": {
+        "agent-gov-core": "github:Conalh/agent-gov-core#v0.1.2"
+      },
       "bin": {
         "taskbound": "dist/index.js"
       },
@@ -26,6 +29,14 @@
         "undici-types": "~7.16.0"
       }
     },
+    "node_modules/agent-gov-core": {
+      "version": "0.1.2",
+      "resolved": "git+ssh://git@github.com/Conalh/agent-gov-core.git#db05618adbd84a503df9b475c49ad86ff161c62e",
+      "license": "MIT",
+      "engines": {
+        "node": ">=20"
+      }
+    },
     "node_modules/typescript": {
       "version": "5.9.3",
       "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.3.tgz",
diff --git a/package.json b/package.json
index 16022bb..8710a43 100644
--- a/package.json
+++ b/package.json
@@ -10,6 +10,9 @@
     "build": "tsc -p tsconfig.json",
     "test": "node --test test/*.test.mjs"
   },
+  "dependencies": {
+    "agent-gov-core": "github:Conalh/agent-gov-core#v0.1.2"
+  },
   "devDependencies": {
     "@types/node": "^24.0.0",
     "typescript": "^5.9.3"
diff --git a/src/discovery.ts b/src/discovery.ts
index ebe6114..473bbbc 100644
--- a/src/discovery.ts
+++ b/src/discovery.ts
@@ -1,5 +1,9 @@
 import { readFile } from 'node:fs/promises';
 import { join } from 'node:path';
+import {
+  lineOfJsonKey as coreLineOfJsonKey,
+  lineOfJsonStringValue as coreLineOfJsonStringValue,
+} from 'agent-gov-core';
 
 export async function readJsonObject(path: string): Promise<Record<string, unknown>> {
   return (await readJsonObjectWithSource(path)).json;
@@ -33,23 +37,13 @@ export function isRecord(value: unknown): value is Record<string, unknown> {
 }
 
 export function lineOfJsonKey(text: string, key: string): number | undefined {
-  const keyPattern = new RegExp(`"${escapeRegExp(key)}"\\s*:`);
-  return lineOfPattern(text, keyPattern);
+  const line = coreLineOfJsonKey(text, key);
+  return line === 0 ? undefined : line;
 }
 
 export function lineOfJsonStringValue(text: string, value: string): number | undefined {
-  const encoded = JSON.stringify(value);
-  return lineOfPattern(text, new RegExp(escapeRegExp(encoded)));
-}
-
-function lineOfPattern(text: string, pattern: RegExp): number | undefined {
-  const lines = text.split(/\r?\n/);
-  const index = lines.findIndex((line) => pattern.test(line));
-  return index === -1 ? undefined : index + 1;
-}
-
-function escapeRegExp(value: string): string {
-  return value.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+  const line = coreLineOfJsonStringValue(text, value);
+  return line === 0 ? undefined : line;
 }
 
 function isNodeError(error: unknown): error is NodeJS.ErrnoException {