diff --git a/sdks/node/README.md b/sdks/node/README.md
index 41b2584..ec4a1ae 100644
--- a/sdks/node/README.md
+++ b/sdks/node/README.md
@@ -95,7 +95,7 @@ Kiro CLI installation covers both runtime contracts. Kiro CLI v2 uses the genera
 | Kiro CLI | `kirocli` |
 | Kiro IDE | `kiroide` |
 | OpenCode | `opencode` |
-| Copilot CLI | `copilot` |
+| GitHub Copilot CLI | `copilot` |
 | Letta Code | `letta` |
 
 ## API Reference
diff --git a/sdks/node/src/plugins/copilot-contract.ts b/sdks/node/src/plugins/copilot-contract.ts
new file mode 100644
index 0000000..e21f2de
--- /dev/null
+++ b/sdks/node/src/plugins/copilot-contract.ts
@@ -0,0 +1,252 @@
+import os from 'node:os';
+import path from 'node:path';
+
+export const AGENT_KEY = 'copilot';
+export const GUARD_SCRIPT = 'guard.js';
+export const AUDIT_SCRIPT = 'hook.js';
+export const HOOK_TIMEOUT_SECONDS = 10;
+export const CONFIG_FILE = 'elydora-audit.json';
+
+export type JsonObject = Record<string, unknown>;
+export type CopilotHooks = Record<string, JsonObject[]>;
+
+export interface CopilotDocument {
+  readonly exists: boolean;
+  readonly filePath: string;
+  readonly root: JsonObject;
+  readonly hooks: CopilotHooks;
+  readonly raw?: string;
+}
+
+export interface CopilotSources {
+  readonly user: CopilotDocument;
+  readonly legacy?: CopilotDocument;
+}
+
+export interface RenderedDocument {
+  readonly document: CopilotDocument;
+  readonly changed: boolean;
+  readonly next?: string;
+}
+
+export interface RuntimeContract {
+  readonly agentId: string;
+  readonly guardPath: string;
+  readonly auditPath: string;
+}
+
+interface ParsedArgument {
+  readonly value: string;
+  readonly next: number;
+}
+
+export function isObject(value: unknown): value is JsonObject {
+  return typeof value === 'object' && value !== null && !Array.isArray(value);
+}
+
+function samePath(left: string, right: string): boolean {
+  const normalizedLeft = path.resolve(left);
+  const normalizedRight = path.resolve(right);
+  return process.platform === 'win32'
+    ? normalizedLeft.toLowerCase() === normalizedRight.toLowerCase()
+    : normalizedLeft === normalizedRight;
+}
+
+function sameAgentId(left: string, right: string): boolean {
+  return process.platform === 'win32' ? left.toLowerCase() === right.toLowerCase() : left === right;
+}
+
+function quotePosix(value: string): string {
+  return `'${value.replaceAll("'", `'"'"'`)}'`;
+}
+
+function quotePowerShell(value: string): string {
+  return `'${value.replaceAll("'", "''")}'`;
+}
+
+export function buildHandler(scriptPath: string): JsonObject {
+  return {
+    type: 'command',
+    bash: `${quotePosix(process.execPath)} ${quotePosix(scriptPath)}`,
+    powershell: `& ${quotePowerShell(process.execPath)} ${quotePowerShell(scriptPath)}; exit $LASTEXITCODE`,
+    timeoutSec: HOOK_TIMEOUT_SECONDS,
+  };
+}
+
+function readPosixArgument(command: string, start: number): ParsedArgument | undefined {
+  if (command[start] !== "'") return undefined;
+  const apostrophe = `'"'"'`;
+  let value = '';
+  for (let index = start + 1; index < command.length;) {
+    if (command.startsWith(apostrophe, index)) {
+      value += "'";
+      index += apostrophe.length;
+      continue;
+    }
+    if (command[index] === "'") return { value, next: index + 1 };
+    value += command[index];
+    index += 1;
+  }
+  return undefined;
+}
+
+function parseGeneratedBash(command: unknown): readonly [string, string] | undefined {
+  if (typeof command !== 'string') return undefined;
+  const executable = readPosixArgument(command, 0);
+  if (!executable || command[executable.next] !== ' ') return undefined;
+  const script = readPosixArgument(command, executable.next + 1);
+  if (!script || script.next !== command.length) return undefined;
+  return [executable.value, script.value];
+}
+
+function readPowerShellArgument(command: string, start: number): ParsedArgument | undefined {
+  if (command[start] !== "'") return undefined;
+  let value = '';
+  for (let index = start + 1; index < command.length; index += 1) {
+    if (command[index] !== "'") {
+      value += command[index];
+      continue;
+    }
+    if (command[index + 1] === "'") {
+      value += "'";
+      index += 1;
+      continue;
+    }
+    return { value, next: index + 1 };
+  }
+  return undefined;
+}
+
+function parseGeneratedPowerShell(command: unknown): readonly [string, string] | undefined {
+  if (typeof command !== 'string' || !command.startsWith('& ')) return undefined;
+  const executable = readPowerShellArgument(command, 2);
+  if (!executable || command[executable.next] !== ' ') return undefined;
+  const script = readPowerShellArgument(command, executable.next + 1);
+  if (!script || command.slice(script.next) !== '; exit $LASTEXITCODE') return undefined;
+  return [executable.value, script.value];
+}
+
+function parseLegacyCommand(command: unknown): string | undefined {
+  if (typeof command !== 'string') return undefined;
+  return /^node(?:\.exe)?\s+"([^"]+)"$/i.exec(command)?.[1];
+}
+
+function managedScriptPath(handler: JsonObject): string | undefined {
+  if (handler.type !== 'command') return undefined;
+  const bash = parseGeneratedBash(handler.bash);
+  const powershell = parseGeneratedPowerShell(handler.powershell);
+  if (handler.timeoutSec === HOOK_TIMEOUT_SECONDS && bash && powershell) {
+    if (samePath(bash[0], process.execPath)
+      && samePath(powershell[0], process.execPath)
+      && samePath(bash[1], powershell[1])) return bash[1];
+  }
+  const legacyBash = parseLegacyCommand(handler.bash);
+  const legacyPowerShell = parseLegacyCommand(handler.powershell);
+  return legacyBash && legacyPowerShell && samePath(legacyBash, legacyPowerShell)
+    ? legacyBash
+    : undefined;
+}
+
+function managedAgentId(handler: JsonObject, scriptName: string): string | undefined {
+  const scriptPath = managedScriptPath(handler);
+  if (!scriptPath || path.basename(scriptPath) !== scriptName) return undefined;
+  const agentDirectory = path.dirname(scriptPath);
+  if (!samePath(path.dirname(agentDirectory), path.join(os.homedir(), '.elydora'))) return undefined;
+  const agentId = path.basename(agentDirectory);
+  return agentId && agentId !== '.' && agentId !== '..' ? agentId : undefined;
+}
+
+function validateHooks(value: unknown, label: string): CopilotHooks {
+  if (value === undefined) return {};
+  if (!isObject(value)) throw new Error(`${label} field "hooks" must be an object`);
+  const hooks: CopilotHooks = {};
+  for (const [event, handlers] of Object.entries(value)) {
+    if (!Array.isArray(handlers)) throw new Error(`${label} field "hooks.${event}" must be an array`);
+    hooks[event] = handlers.map((handler, index) => {
+      if (!isObject(handler)) throw new Error(`${label} handler hooks.${event}[${index}] must be an object`);
+      return handler;
+    });
+  }
+  return hooks;
+}
+
+export function parseDocument(filePath: string, raw: string, label: string): CopilotDocument {
+  let value: unknown;
+  try {
+    value = JSON.parse(raw);
+  } catch (error) {
+    const message = error instanceof Error ? error.message : String(error);
+    throw new Error(`Failed to parse ${label} at ${filePath}: ${message}`, { cause: error });
+  }
+  if (!isObject(value)) throw new Error(`${label} at ${filePath} must contain a JSON object`);
+  if (value.version !== 1) throw new Error(`${label} at ${filePath} must declare version 1`);
+  return {
+    exists: true,
+    filePath,
+    root: value,
+    hooks: validateHooks(value.hooks, label),
+    raw,
+  };
+}
+
+export function createDocument(filePath: string): CopilotDocument {
+  return { exists: false, filePath, root: {}, hooks: {} };
+}
+
+export function removeManagedHooks(hooks: CopilotHooks, agentId?: string): CopilotHooks {
+  const next: CopilotHooks = { ...hooks };
+  for (const [event, scriptName] of [
+    ['preToolUse', GUARD_SCRIPT],
+    ['postToolUse', AUDIT_SCRIPT],
+  ] as const) {
+    const handlers = (next[event] ?? []).filter((handler) => {
+      const managedId = managedAgentId(handler, scriptName);
+      return !managedId || (agentId !== undefined && !sameAgentId(managedId, agentId));
+    });
+    if (handlers.length > 0) next[event] = handlers;
+    else delete next[event];
+  }
+  return next;
+}
+
+function isEmptyOwnedDocument(root: JsonObject, hooks: CopilotHooks): boolean {
+  return Object.keys(hooks).length === 0
+    && Object.keys(root).every((key) => key === 'version' || key === 'hooks');
+}
+
+export function renderDocument(
+  document: CopilotDocument,
+  hooks: CopilotHooks,
+): RenderedDocument {
+  if (!document.exists && Object.keys(hooks).length === 0) {
+    return { document, changed: false };
+  }
+  if (document.exists && isEmptyOwnedDocument(document.root, hooks)) {
+    return { document, changed: true };
+  }
+  const root: JsonObject = { ...document.root, version: 1 };
+  if (Object.keys(hooks).length > 0) root.hooks = hooks;
+  else delete root.hooks;
+  const next = JSON.stringify(root, null, 2) + '\n';
+  return { document, changed: next !== document.raw, next };
+}
+
+function managedIds(handlers: JsonObject[], scriptName: string): Set<string> {
+  return new Set(handlers.flatMap((handler) => {
+    const agentId = managedAgentId(handler, scriptName);
+    return agentId ? [agentId] : [];
+  }));
+}
+
+export function runtimeContracts(hooks: CopilotHooks): RuntimeContract[] {
+  const guards = managedIds(hooks.preToolUse ?? [], GUARD_SCRIPT);
+  const audits = managedIds(hooks.postToolUse ?? [], AUDIT_SCRIPT);
+  const root = path.join(os.homedir(), '.elydora');
+  return [...guards]
+    .filter((agentId) => [...audits].some((auditId) => sameAgentId(agentId, auditId)))
+    .map((agentId) => ({
+      agentId,
+      guardPath: path.join(root, agentId, GUARD_SCRIPT),
+      auditPath: path.join(root, agentId, AUDIT_SCRIPT),
+    }));
+}
diff --git a/sdks/node/src/plugins/copilot-io.ts b/sdks/node/src/plugins/copilot-io.ts
new file mode 100644
index 0000000..a64df9c
--- /dev/null
+++ b/sdks/node/src/plugins/copilot-io.ts
@@ -0,0 +1,281 @@
+import { randomUUID } from 'node:crypto';
+import fsp from 'node:fs/promises';
+import type { FileHandle } from 'node:fs/promises';
+import os from 'node:os';
+import path from 'node:path';
+import {
+  AGENT_KEY,
+  CONFIG_FILE,
+  type CopilotDocument,
+  type CopilotSources,
+  type JsonObject,
+  type RenderedDocument,
+  type RuntimeContract,
+  createDocument,
+  isObject,
+  parseDocument,
+} from './copilot-contract.js';
+
+interface FileChange {
+  readonly filePath: string;
+  readonly label: string;
+  readonly original?: string;
+  readonly next?: string;
+}
+
+interface StagedChange {
+  readonly change: FileChange;
+  readonly tempPath?: string;
+  readonly rollbackPath?: string;
+  committed: boolean;
+}
+
+function errorMessage(error: unknown): string {
+  return error instanceof Error ? error.message : String(error);
+}
+
+function asError(error: unknown): Error {
+  return error instanceof Error ? error : new Error(String(error));
+}
+
+function hasErrorCode(error: unknown, code: string): boolean {
+  return isObject(error) && error.code === code;
+}
+
+function paths(): { readonly user: string; readonly legacy: string } {
+  const override = process.env.COPILOT_HOME?.trim();
+  const copilotHome = override || path.join(os.homedir(), '.copilot');
+  return {
+    user: path.join(copilotHome, 'hooks', CONFIG_FILE),
+    legacy: path.join(process.cwd(), '.github', 'hooks', 'hooks.json'),
+  };
+}
+
+async function readOptional(filePath: string, label: string): Promise<string | undefined> {
+  try {
+    return await fsp.readFile(filePath, 'utf-8');
+  } catch (error) {
+    if (hasErrorCode(error, 'ENOENT')) return undefined;
+    throw new Error(`Read ${label} at ${filePath}: ${errorMessage(error)}`, {
+      cause: asError(error),
+    });
+  }
+}
+
+async function readDocument(filePath: string, label: string): Promise<CopilotDocument | undefined> {
+  const raw = await readOptional(filePath, label);
+  return raw === undefined ? undefined : parseDocument(filePath, raw, label);
+}
+
+export async function readSources(): Promise<CopilotSources> {
+  const configPaths = paths();
+  const [user, legacy] = await Promise.all([
+    readDocument(configPaths.user, 'GitHub Copilot user hooks'),
+    readDocument(configPaths.legacy, 'GitHub Copilot legacy project hooks'),
+  ]);
+  return {
+    user: user ?? createDocument(configPaths.user),
+    legacy,
+  };
+}
+
+function changeFor(rendered: RenderedDocument): FileChange | undefined {
+  if (!rendered.changed) return undefined;
+  return {
+    filePath: rendered.document.filePath,
+    label: 'GitHub Copilot hook source',
+    original: rendered.document.raw,
+    next: rendered.next,
+  };
+}
+
+async function unlinkOptional(filePath: string): Promise<void> {
+  try {
+    await fsp.unlink(filePath);
+  } catch (error) {
+    if (!hasErrorCode(error, 'ENOENT')) throw error;
+  }
+}
+
+async function writeExclusive(filePath: string, contents: string, label: string): Promise<void> {
+  let handle: FileHandle | undefined;
+  try {
+    handle = await fsp.open(filePath, 'wx', 0o600);
+    await handle.writeFile(contents, 'utf-8');
+    await handle.sync();
+    await handle.close();
+    handle = undefined;
+  } catch (error) {
+    const failures = [asError(error)];
+    if (handle) {
+      try {
+        await handle.close();
+      } catch (closeError) {
+        failures.push(asError(closeError));
+      }
+    }
+    try {
+      await unlinkOptional(filePath);
+    } catch (cleanupError) {
+      failures.push(asError(cleanupError));
+    }
+    if (failures.length > 1) throw new AggregateError(failures, `Stage ${label}`);
+    throw new Error(`Stage ${label}: ${errorMessage(error)}`, { cause: failures[0] });
+  }
+}
+
+async function assertUnchanged(change: FileChange): Promise<void> {
+  const current = await readOptional(change.filePath, change.label);
+  if (current !== change.original) {
+    throw new Error(`${change.label} changed during Copilot hook update: ${change.filePath}`);
+  }
+}
+
+async function stage(change: FileChange): Promise<StagedChange> {
+  await assertUnchanged(change);
+  const directory = path.dirname(change.filePath);
+  await fsp.mkdir(directory, { recursive: true, mode: 0o700 });
+  const token = randomUUID();
+  const tempPath = change.next === undefined
+    ? undefined
+    : path.join(directory, `.${path.basename(change.filePath)}.${token}.tmp`);
+  const rollbackPath = change.original === undefined
+    ? undefined
+    : path.join(directory, `.${path.basename(change.filePath)}.${token}.rollback`);
+  try {
+    if (tempPath) await writeExclusive(tempPath, change.next!, change.label);
+    if (rollbackPath && change.next !== undefined) {
+      await writeExclusive(rollbackPath, change.original!, `${change.label} rollback`);
+    }
+  } catch (error) {
+    const failures = [asError(error)];
+    for (const stagedPath of [tempPath, rollbackPath]) {
+      if (!stagedPath) continue;
+      try {
+        await unlinkOptional(stagedPath);
+      } catch (cleanupError) {
+        failures.push(asError(cleanupError));
+      }
+    }
+    if (failures.length > 1) throw new AggregateError(failures, `Stage ${change.label}`);
+    throw error;
+  }
+  return { change, tempPath, rollbackPath, committed: false };
+}
+
+async function commit(staged: StagedChange): Promise<void> {
+  await assertUnchanged(staged.change);
+  if (staged.change.next === undefined) {
+    if (!staged.rollbackPath) throw new Error(`Missing rollback path for ${staged.change.label}`);
+    await fsp.rename(staged.change.filePath, staged.rollbackPath);
+  } else {
+    if (!staged.tempPath) throw new Error(`Missing staged file for ${staged.change.label}`);
+    await fsp.rename(staged.tempPath, staged.change.filePath);
+  }
+  staged.committed = true;
+}
+
+async function rollback(staged: StagedChange): Promise<void> {
+  if (!staged.committed) return;
+  if (staged.change.original === undefined) {
+    await unlinkOptional(staged.change.filePath);
+    return;
+  }
+  if (!staged.rollbackPath) throw new Error(`Missing rollback data for ${staged.change.label}`);
+  await fsp.rename(staged.rollbackPath, staged.change.filePath);
+}
+
+async function cleanup(staged: StagedChange): Promise<void> {
+  const files = [staged.tempPath, staged.rollbackPath].filter(
+    (filePath): filePath is string => filePath !== undefined,
+  );
+  await Promise.all(files.map(unlinkOptional));
+}
+
+export async function writeDocuments(rendered: RenderedDocument[]): Promise<void> {
+  const changes = rendered.flatMap((document) => {
+    const change = changeFor(document);
+    return change ? [change] : [];
+  });
+  const staged: StagedChange[] = [];
+  try {
+    for (const change of changes) staged.push(await stage(change));
+    for (const item of staged) await commit(item);
+  } catch (error) {
+    const failures = [asError(error)];
+    for (const item of [...staged].reverse()) {
+      try {
+        await rollback(item);
+      } catch (rollbackError) {
+        failures.push(asError(rollbackError));
+      }
+    }
+    for (const item of staged) {
+      try {
+        await cleanup(item);
+      } catch (cleanupError) {
+        failures.push(asError(cleanupError));
+      }
+    }
+    throw new AggregateError(failures, `Write GitHub Copilot hook sources: ${errorMessage(error)}`);
+  }
+  const cleanupErrors: Error[] = [];
+  for (const item of staged) {
+    try {
+      await cleanup(item);
+    } catch (error) {
+      cleanupErrors.push(asError(error));
+    }
+  }
+  if (cleanupErrors.length > 0) {
+    throw new AggregateError(cleanupErrors, 'Clean GitHub Copilot hook transaction files');
+  }
+}
+
+export async function regularFileExists(filePath: string, label: string): Promise<boolean> {
+  try {
+    return (await fsp.stat(filePath)).isFile();
+  } catch (error) {
+    if (hasErrorCode(error, 'ENOENT') || hasErrorCode(error, 'ENOTDIR')) return false;
+    throw new Error(`Read ${label} at ${filePath}: ${errorMessage(error)}`, {
+      cause: asError(error),
+    });
+  }
+}
+
+export async function requireRuntime(filePath: string, label: string): Promise<void> {
+  if (!filePath) throw new Error(`${label} path is required`);
+  if (!await regularFileExists(filePath, label)) throw new Error(`${label} is missing: ${filePath}`);
+}
+
+async function readRuntimeConfig(filePath: string): Promise<JsonObject | undefined> {
+  const raw = await readOptional(filePath, 'Elydora runtime config');
+  if (raw === undefined) return undefined;
+  let value: unknown;
+  try {
+    value = JSON.parse(raw);
+  } catch (error) {
+    throw new Error(`Failed to parse Elydora runtime config at ${filePath}: ${errorMessage(error)}`, {
+      cause: asError(error),
+    });
+  }
+  if (!isObject(value)) throw new Error(`Elydora runtime config at ${filePath} must contain a JSON object`);
+  return value;
+}
+
+export async function runtimeFilesExist(contracts: RuntimeContract[]): Promise<boolean> {
+  for (const contract of contracts) {
+    const runtimeConfig = await readRuntimeConfig(
+      path.join(path.dirname(contract.guardPath), 'config.json'),
+    );
+    if (!runtimeConfig
+      || runtimeConfig.agent_name !== AGENT_KEY
+      || runtimeConfig.agent_id !== contract.agentId) continue;
+    const files = await Promise.all([
+      regularFileExists(contract.guardPath, 'Elydora guard runtime'),
+      regularFileExists(contract.auditPath, 'Elydora audit runtime'),
+    ]);
+    if (files.every(Boolean)) return true;
+  }
+  return false;
+}
diff --git a/sdks/node/src/plugins/copilot.ts b/sdks/node/src/plugins/copilot.ts
index b5870b1..d027e18 100644
--- a/sdks/node/src/plugins/copilot.ts
+++ b/sdks/node/src/plugins/copilot.ts
@@ -1,164 +1,89 @@
-import fsp from 'node:fs/promises';
-import path from 'node:path';
 import type { AgentPlugin, InstallConfig, PluginStatus } from './base.js';
+import {
+  AGENT_KEY,
+  AUDIT_SCRIPT,
+  GUARD_SCRIPT,
+  buildHandler,
+  removeManagedHooks,
+  renderDocument,
+  runtimeContracts,
+} from './copilot-contract.js';
+import {
+  readSources,
+  requireRuntime,
+  runtimeFilesExist,
+  writeDocuments,
+} from './copilot-io.js';
 import { SUPPORTED_AGENTS } from './registry.js';
 
-const AGENT_KEY = 'copilot';
 const entry = SUPPORTED_AGENTS.get(AGENT_KEY)!;
 
-function resolveConfigDir(): string {
-  return path.join(process.cwd(), entry.configDir);
-}
-
-function resolveConfigPath(): string {
-  return path.join(resolveConfigDir(), entry.configFile);
-}
-
-function buildHookCommand(scriptPath: string): string {
-  return `node "${scriptPath}"`;
-}
-
-function isElydoraCommand(cmd: string, agentId?: string): boolean {
-  if (!cmd.includes('elydora')) return false;
-  if (agentId) {
-    return cmd.includes(agentId);
-  }
-  return true;
-}
-
-function filterElydoraEntries(arr: Array<Record<string, unknown>>, agentId?: string): Array<Record<string, unknown>> {
-  return arr.filter((h) => {
-    if (typeof h.bash === 'string' && isElydoraCommand(h.bash, agentId)) return false;
-    if (typeof h.powershell === 'string' && isElydoraCommand(h.powershell, agentId)) return false;
-    return true;
-  });
+function mergedContracts(
+  userHooks: Parameters<typeof runtimeContracts>[0],
+  legacyHooks?: Parameters<typeof runtimeContracts>[0],
+): ReturnType<typeof runtimeContracts> {
+  const contracts = [
+    ...runtimeContracts(userHooks),
+    ...runtimeContracts(legacyHooks ?? {}),
+  ];
+  const unique = new Map(contracts.map((contract) => [contract.agentId, contract]));
+  return [...unique.values()];
 }
 
 export const copilotPlugin: AgentPlugin = {
   async install(config: InstallConfig): Promise<void> {
-    const configDir = resolveConfigDir();
-    await fsp.mkdir(configDir, { recursive: true });
+    if (!config.agentId) throw new Error('agentId is required');
+    const sources = await readSources();
+    await requireRuntime(config.guardScriptPath, 'Elydora guard runtime');
+    await requireRuntime(config.hookScriptPath, 'Elydora audit runtime');
 
-    const configPath = resolveConfigPath();
-    let settings: Record<string, unknown> = { version: 1 };
+    const userHooks = removeManagedHooks(sources.user.hooks);
+    userHooks.preToolUse = [
+      ...(userHooks.preToolUse ?? []),
+      buildHandler(config.guardScriptPath),
+    ];
+    userHooks.postToolUse = [
+      ...(userHooks.postToolUse ?? []),
+      buildHandler(config.hookScriptPath),
+    ];
 
-    try {
-      const raw = await fsp.readFile(configPath, 'utf-8');
-      settings = JSON.parse(raw);
-    } catch {
-      // Start fresh
+    const rendered = [renderDocument(sources.user, userHooks)];
+    if (sources.legacy) {
+      rendered.push(renderDocument(
+        sources.legacy,
+        removeManagedHooks(sources.legacy.hooks),
+      ));
     }
-
-    settings.version = 1;
-
-    if (!settings.hooks || typeof settings.hooks !== 'object') {
-      settings.hooks = {};
-    }
-    const hooks = settings.hooks as Record<string, unknown>;
-
-    // --- preToolUse (guard — freeze enforcement) ---
-    if (!Array.isArray(hooks.preToolUse)) {
-      hooks.preToolUse = [];
-    }
-    const preFiltered = filterElydoraEntries(hooks.preToolUse as Array<Record<string, unknown>>);
-    preFiltered.push({
-      type: 'command',
-      bash: buildHookCommand(config.guardScriptPath),
-      powershell: buildHookCommand(config.guardScriptPath),
-      timeoutSec: 5,
-    });
-    hooks.preToolUse = preFiltered;
-
-    // --- postToolUse (audit logging) ---
-    if (!Array.isArray(hooks.postToolUse)) {
-      hooks.postToolUse = [];
-    }
-    const postFiltered = filterElydoraEntries(hooks.postToolUse as Array<Record<string, unknown>>);
-    postFiltered.push({
-      type: 'command',
-      bash: buildHookCommand(config.hookScriptPath),
-      powershell: buildHookCommand(config.hookScriptPath),
-      timeoutSec: 5,
-    });
-    hooks.postToolUse = postFiltered;
-
-    settings.hooks = hooks;
-    await fsp.writeFile(configPath, JSON.stringify(settings, null, 2) + '\n', 'utf-8');
+    await writeDocuments(rendered);
+    console.log(`  GitHub Copilot CLI hooks: ${sources.user.filePath}`);
   },
 
   async uninstall(agentId?: string): Promise<void> {
-    const configPath = resolveConfigPath();
-
-    let settings: Record<string, unknown>;
-    try {
-      const raw = await fsp.readFile(configPath, 'utf-8');
-      settings = JSON.parse(raw);
-    } catch {
-      return;
+    const sources = await readSources();
+    const rendered = [
+      renderDocument(sources.user, removeManagedHooks(sources.user.hooks, agentId)),
+    ];
+    if (sources.legacy) {
+      rendered.push(renderDocument(
+        sources.legacy,
+        removeManagedHooks(sources.legacy.hooks, agentId),
+      ));
     }
-
-    const hooks = settings.hooks as Record<string, unknown> | undefined;
-    if (!hooks) return;
-
-    if (Array.isArray(hooks.preToolUse)) {
-      hooks.preToolUse = filterElydoraEntries(hooks.preToolUse as Array<Record<string, unknown>>, agentId);
-    }
-    if (Array.isArray(hooks.postToolUse)) {
-      hooks.postToolUse = filterElydoraEntries(hooks.postToolUse as Array<Record<string, unknown>>, agentId);
-    }
-
-    await fsp.writeFile(configPath, JSON.stringify(settings, null, 2) + '\n', 'utf-8');
+    await writeDocuments(rendered);
   },
 
   async status(): Promise<PluginStatus> {
-    const configPath = resolveConfigPath();
-
-    let hookConfigured = false;
-    let hookScriptPath = '';
-    try {
-      const raw = await fsp.readFile(configPath, 'utf-8');
-      const settings = JSON.parse(raw);
-      const hooks = settings.hooks as Record<string, unknown> | undefined;
-      if (hooks) {
-        const check = (arr: unknown) =>
-          Array.isArray(arr) && (arr as Array<Record<string, unknown>>).some(
-            (h) =>
-              (typeof h.bash === 'string' && h.bash.includes('elydora')) ||
-              (typeof h.powershell === 'string' && h.powershell.includes('elydora')),
-          );
-        hookConfigured = check(hooks.preToolUse) && check(hooks.postToolUse);
-
-        // Extract hook script path from postToolUse bash/powershell command
-        if (hookConfigured && Array.isArray(hooks.postToolUse)) {
-          for (const h of hooks.postToolUse as Array<Record<string, unknown>>) {
-            const cmd = (h.bash || h.powershell) as string;
-            if (cmd && cmd.includes('elydora')) {
-              hookScriptPath = cmd.replace(/^node\s+"?/, '').replace(/"?\s*$/, '');
-            }
-          }
-        }
-      }
-    } catch {
-      // Config not readable
-    }
-
-    let hookScriptExists = false;
-    if (hookScriptPath) {
-      try {
-        await fsp.access(hookScriptPath);
-        hookScriptExists = true;
-      } catch {
-        // File doesn't exist
-      }
-    }
-
+    const sources = await readSources();
+    const contracts = mergedContracts(sources.user.hooks, sources.legacy?.hooks);
+    const hookConfigured = contracts.length > 0;
+    const hookScriptExists = hookConfigured && await runtimeFilesExist(contracts);
     return {
       installed: hookConfigured && hookScriptExists,
       agentName: AGENT_KEY,
       displayName: entry.name,
       hookConfigured,
       hookScriptExists,
-      configPath,
+      configPath: sources.user.filePath,
     };
   },
 };
diff --git a/sdks/node/src/plugins/registry.ts b/sdks/node/src/plugins/registry.ts
index 7a4c323..9228d3a 100644
--- a/sdks/node/src/plugins/registry.ts
+++ b/sdks/node/src/plugins/registry.ts
@@ -12,7 +12,7 @@ export const SUPPORTED_AGENTS: ReadonlyMap<string, AgentRegistryEntry> = new Map
   ['kirocli', { name: 'Kiro CLI', configDir: '~/.kiro/hooks', configFile: 'elydora-audit.json' }],
   ['kiroide', { name: 'Kiro IDE', configDir: '.kiro/hooks', configFile: 'elydora-audit.kiro.hook' }],
   ['opencode', { name: 'OpenCode', configDir: '.config/opencode/plugins', configFile: 'elydora-audit.mjs' }],
-  ['copilot', { name: 'Copilot CLI', configDir: '.github/hooks', configFile: 'hooks.json' }],
+  ['copilot', { name: 'GitHub Copilot CLI', configDir: '~/.copilot/hooks', configFile: 'elydora-audit.json' }],
   ['letta', { name: 'Letta Code', configDir: '~/.letta', configFile: 'settings.json' }],
   ['codex', { name: 'OpenAI Codex', configDir: '~/.codex', configFile: 'hooks.json' }],
   ['cline', { name: 'Cline', configDir: '~/.cline/hooks', configFile: 'PreToolUse.mjs' }],
diff --git a/sdks/node/test/copilot-plugin.test.mjs b/sdks/node/test/copilot-plugin.test.mjs
new file mode 100644
index 0000000..25c1121
--- /dev/null
+++ b/sdks/node/test/copilot-plugin.test.mjs
@@ -0,0 +1,389 @@
+import assert from 'node:assert/strict';
+import { spawn } from 'node:child_process';
+import { mkdtemp, mkdir, readFile, readdir, rm, writeFile } from 'node:fs/promises';
+import os from 'node:os';
+import path from 'node:path';
+import test from 'node:test';
+import { pathToFileURL } from 'node:url';
+
+const pluginModuleUrl = pathToFileURL(path.resolve('dist/plugins/copilot.js')).href;
+const registryModuleUrl = pathToFileURL(path.resolve('dist/plugins/registry.js')).href;
+
+function runNode(args, env, cwd, input = '') {
+  return new Promise((resolve, reject) => {
+    const child = spawn(process.execPath, args, {
+      cwd,
+      env: { ...process.env, ...env },
+      stdio: ['pipe', 'pipe', 'pipe'],
+    });
+    let stdout = '';
+    let stderr = '';
+    child.stdout.on('data', (chunk) => { stdout += chunk; });
+    child.stderr.on('data', (chunk) => { stderr += chunk; });
+    child.once('error', reject);
+    child.once('close', (code) => resolve({ code, stdout, stderr }));
+    child.stdin.end(input);
+  });
+}
+
+function runHook(handler, input) {
+  const command = process.platform === 'win32'
+    ? ['powershell.exe', ['-NoProfile', '-NonInteractive', '-Command', handler.powershell]]
+    : ['/bin/sh', ['-c', handler.bash]];
+  return new Promise((resolve, reject) => {
+    const child = spawn(command[0], command[1], { stdio: ['pipe', 'pipe', 'pipe'] });
+    let stdout = '';
+    let stderr = '';
+    child.stdout.on('data', (chunk) => { stdout += chunk; });
+    child.stderr.on('data', (chunk) => { stderr += chunk; });
+    child.once('error', reject);
+    child.once('close', (code) => resolve({ code, stdout, stderr }));
+    child.stdin.end(input);
+  });
+}
+
+async function writeJson(filePath, value) {
+  await mkdir(path.dirname(filePath), { recursive: true });
+  await writeFile(filePath, typeof value === 'string' ? value : JSON.stringify(value, null, 2));
+}
+
+async function runPlugin(fixture, method, argument) {
+  const source = `
+    import { copilotPlugin } from ${JSON.stringify(pluginModuleUrl)};
+    const argument = JSON.parse(process.env.ELYDORA_TEST_ARGUMENT);
+    const result = await copilotPlugin[process.env.ELYDORA_TEST_METHOD](argument);
+    if (result !== undefined) console.log(JSON.stringify(result));
+  `;
+  return runNode(
+    ['--input-type=module', '--eval', source],
+    {
+      HOME: fixture.homeDir,
+      USERPROFILE: fixture.homeDir,
+      COPILOT_HOME: fixture.copilotHome,
+      ELYDORA_TEST_ARGUMENT: JSON.stringify(argument),
+      ELYDORA_TEST_METHOD: method,
+    },
+    fixture.projectDir,
+  );
+}
+
+async function createFixture({
+  userConfig,
+  legacyConfig,
+  guardSource,
+  hookSource,
+  createRuntimes = true,
+} = {}) {
+  const homeDir = await mkdtemp(path.join(os.tmpdir(), 'elydora-copilot-'));
+  const projectDir = path.join(homeDir, 'project');
+  const copilotHome = path.join(homeDir, 'custom-copilot');
+  const configPath = path.join(copilotHome, 'hooks', 'elydora-audit.json');
+  const legacyPath = path.join(projectDir, '.github', 'hooks', 'hooks.json');
+  const agentDir = path.join(homeDir, '.elydora', 'agent-1');
+  const guardScriptPath = path.join(agentDir, 'guard.js');
+  const hookScriptPath = path.join(agentDir, 'hook.js');
+  await mkdir(projectDir, { recursive: true });
+  if (createRuntimes) {
+    await mkdir(agentDir, { recursive: true });
+    await writeFile(
+      guardScriptPath,
+      guardSource ?? "process.stdin.resume(); process.stdin.once('end', () => { process.stderr.write('Agent is frozen by Elydora.'); process.exit(2); });\n",
+    );
+    await writeFile(hookScriptPath, hookSource ?? 'process.stdin.resume();\n');
+    await writeFile(path.join(agentDir, 'config.json'), JSON.stringify({
+      agent_id: 'agent-1',
+      agent_name: 'copilot',
+    }));
+  }
+  if (userConfig !== undefined) await writeJson(configPath, userConfig);
+  if (legacyConfig !== undefined) await writeJson(legacyPath, legacyConfig);
+  return {
+    agentDir,
+    configPath,
+    copilotHome,
+    guardScriptPath,
+    homeDir,
+    hookScriptPath,
+    legacyPath,
+    projectDir,
+    async install() {
+      return runPlugin(this, 'install', {
+        agentName: 'copilot',
+        agentId: 'agent-1',
+        guardScriptPath,
+        hookScriptPath,
+      });
+    },
+    async close() {
+      await rm(homeDir, { recursive: true, force: true });
+    },
+  };
+}
+
+function managedHandler(config, event, scriptName) {
+  return config.hooks?.[event]?.find(
+    (handler) => handler.bash?.includes(scriptName) || handler.powershell?.includes(scriptName),
+  );
+}
+
+function assertNativeHandler(handler) {
+  assert.deepEqual(Object.keys(handler).sort(), ['bash', 'powershell', 'timeoutSec', 'type']);
+  assert.equal(handler.type, 'command');
+  assert.equal(handler.timeoutSec, 10);
+  assert.match(handler.bash, /node(?:\.exe)?/i);
+  assert.match(handler.powershell, /^& /);
+}
+
+function legacyManagedConfig(fixture, extraHooks = {}) {
+  return {
+    version: 1,
+    hooks: {
+      preToolUse: [{
+        type: 'command',
+        bash: `node "${fixture.guardScriptPath}"`,
+        powershell: `node "${fixture.guardScriptPath}"`,
+        timeoutSec: 5,
+      }],
+      postToolUse: [{
+        type: 'command',
+        bash: `node "${fixture.hookScriptPath}"`,
+        powershell: `node "${fixture.hookScriptPath}"`,
+        timeoutSec: 5,
+      }],
+      ...extraHooks,
+    },
+  };
+}
+
+test('GitHub Copilot CLI is registered with the native user hook file', async () => {
+  const { SUPPORTED_AGENTS } = await import(registryModuleUrl);
+  assert.deepEqual(SUPPORTED_AGENTS.get('copilot'), {
+    name: 'GitHub Copilot CLI',
+    configDir: '~/.copilot/hooks',
+    configFile: 'elydora-audit.json',
+  });
+});
+
+test('Copilot install preserves user hooks, migrates legacy entries, and is idempotent', async () => {
+  const fixture = await createFixture({
+    userConfig: {
+      version: 1,
+      disableAllHooks: false,
+      hooks: {
+        sessionStart: [{ type: 'command', command: 'user-session-hook' }],
+        preToolUse: [{ type: 'command', command: 'user-pre-hook' }],
+      },
+    },
+  });
+  try {
+    await writeJson(fixture.legacyPath, legacyManagedConfig(fixture, {
+      notification: [{ type: 'command', command: 'user-notification-hook' }],
+    }));
+
+    const first = await fixture.install();
+    assert.equal(first.code, 0, first.stderr);
+    const second = await fixture.install();
+    assert.equal(second.code, 0, second.stderr);
+
+    const config = JSON.parse(await readFile(fixture.configPath, 'utf-8'));
+    assert.equal(config.version, 1);
+    assert.equal(config.disableAllHooks, false);
+    assert.deepEqual(config.hooks.sessionStart, [{ type: 'command', command: 'user-session-hook' }]);
+    assert.deepEqual(config.hooks.preToolUse[0], { type: 'command', command: 'user-pre-hook' });
+    assert.equal(config.hooks.preToolUse.length, 2);
+    assert.equal(config.hooks.postToolUse.length, 1);
+    assertNativeHandler(managedHandler(config, 'preToolUse', 'guard.js'));
+    assertNativeHandler(managedHandler(config, 'postToolUse', 'hook.js'));
+
+    const legacy = JSON.parse(await readFile(fixture.legacyPath, 'utf-8'));
+    assert.deepEqual(legacy, {
+      version: 1,
+      hooks: {
+        notification: [{ type: 'command', command: 'user-notification-hook' }],
+      },
+    });
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('Copilot migration removes a legacy file owned entirely by Elydora', async () => {
+  const fixture = await createFixture();
+  try {
+    await writeJson(fixture.legacyPath, legacyManagedConfig(fixture));
+    const result = await fixture.install();
+    assert.equal(result.code, 0, result.stderr);
+    await assert.rejects(readFile(fixture.legacyPath), { code: 'ENOENT' });
+    const config = JSON.parse(await readFile(fixture.configPath, 'utf-8'));
+    assertNativeHandler(managedHandler(config, 'preToolUse', 'guard.js'));
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('Copilot commands block freezes and forward the native payload byte-for-byte', async () => {
+  const capturePath = path.join(os.tmpdir(), `elydora-copilot-event-${process.pid}-${Date.now()}.json`);
+  const fixture = await createFixture({
+    hookSource: `
+      const fs = require('node:fs');
+      const chunks = [];
+      process.stdin.on('data', (chunk) => chunks.push(chunk));
+      process.stdin.on('end', () => fs.writeFileSync(${JSON.stringify(capturePath)}, Buffer.concat(chunks)));
+    `,
+  });
+  try {
+    const install = await fixture.install();
+    assert.equal(install.code, 0, install.stderr);
+    const config = JSON.parse(await readFile(fixture.configPath, 'utf-8'));
+    const guard = managedHandler(config, 'preToolUse', 'guard.js');
+    const audit = managedHandler(config, 'postToolUse', 'hook.js');
+    const prePayload = JSON.stringify({
+      sessionId: 'session-1',
+      timestamp: Date.now(),
+      cwd: fixture.projectDir,
+      toolName: 'powershell',
+      toolArgs: { command: 'Get-ChildItem' },
+    });
+    const guardResult = await runHook(guard, prePayload);
+    assert.equal(guardResult.code, 2, guardResult.stderr);
+    assert.match(guardResult.stderr, /Agent is frozen by Elydora/);
+
+    const postPayload = JSON.stringify({
+      sessionId: 'session-1',
+      timestamp: Date.now(),
+      cwd: fixture.projectDir,
+      toolName: 'powershell',
+      toolArgs: { command: 'Get-ChildItem' },
+      toolResult: { output: 'ok' },
+    });
+    const auditResult = await runHook(audit, postPayload);
+    assert.equal(auditResult.code, 0, auditResult.stderr);
+    assert.equal(await readFile(capturePath, 'utf-8'), postPayload);
+  } finally {
+    await fixture.close();
+    await rm(capturePath, { force: true });
+  }
+});
+
+test('Copilot treats an empty home override as the official default', async () => {
+  const fixture = await createFixture();
+  try {
+    fixture.copilotHome = '';
+    const result = await fixture.install();
+    assert.equal(result.code, 0, result.stderr);
+    const defaultPath = path.join(fixture.homeDir, '.copilot', 'hooks', 'elydora-audit.json');
+    const config = JSON.parse(await readFile(defaultPath, 'utf-8'));
+    assertNativeHandler(managedHandler(config, 'preToolUse', 'guard.js'));
+    const status = await runPlugin(fixture, 'status', null);
+    assert.equal(JSON.parse(status.stdout).configPath, defaultPath);
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('Copilot status requires a complete pair, matching runtime identity, and both scripts', async () => {
+  const fixture = await createFixture();
+  try {
+    assert.equal((await fixture.install()).code, 0);
+    let status = await runPlugin(fixture, 'status', null);
+    assert.equal(status.code, 0, status.stderr);
+    assert.equal(JSON.parse(status.stdout).installed, true);
+
+    const config = JSON.parse(await readFile(fixture.configPath, 'utf-8'));
+    delete config.hooks.postToolUse;
+    await writeJson(fixture.configPath, config);
+    status = await runPlugin(fixture, 'status', null);
+    assert.equal(JSON.parse(status.stdout).hookConfigured, false);
+
+    assert.equal((await fixture.install()).code, 0);
+    await writeFile(path.join(fixture.agentDir, 'config.json'), '{ malformed');
+    status = await runPlugin(fixture, 'status', null);
+    assert.equal(status.code, 1);
+    assert.match(status.stderr, /parse Elydora runtime config/i);
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('Copilot uninstall removes exact ownership and preserves user entries', async () => {
+  const fixture = await createFixture({
+    userConfig: { version: 1, hooks: { notification: [{ type: 'command', command: 'keep' }] } },
+  });
+  try {
+    assert.equal((await fixture.install()).code, 0);
+    const config = JSON.parse(await readFile(fixture.configPath, 'utf-8'));
+    config.hooks.preToolUse.push({
+      type: 'command',
+      bash: `'${process.execPath}' '${path.join(fixture.homeDir, '.elydora', 'agent-10', 'guard.js')}'`,
+      powershell: 'user-decoy',
+      timeoutSec: 10,
+    });
+    await writeJson(fixture.configPath, config);
+
+    const result = await runPlugin(fixture, 'uninstall', 'agent-1');
+    assert.equal(result.code, 0, result.stderr);
+    const remaining = JSON.parse(await readFile(fixture.configPath, 'utf-8'));
+    assert.deepEqual(remaining.hooks.notification, [{ type: 'command', command: 'keep' }]);
+    assert.equal(remaining.hooks.postToolUse, undefined);
+    assert.equal(remaining.hooks.preToolUse.length, 1);
+    assert.match(remaining.hooks.preToolUse[0].bash, /agent-10/);
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('Copilot uninstall leaves absent hook sources absent', async () => {
+  const fixture = await createFixture();
+  try {
+    const result = await runPlugin(fixture, 'uninstall', 'agent-1');
+    assert.equal(result.code, 0, result.stderr);
+    await assert.rejects(readFile(fixture.configPath), { code: 'ENOENT' });
+    await assert.rejects(readFile(fixture.legacyPath), { code: 'ENOENT' });
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('Copilot preserves malformed and invalid configs for recovery', async () => {
+  for (const existing of [
+    '{ malformed',
+    { hooks: {} },
+    { version: 2, hooks: {} },
+    { version: 1, hooks: null },
+    { version: 1, hooks: { preToolUse: null } },
+    { version: 1, hooks: { preToolUse: [null] } },
+  ]) {
+    const fixture = await createFixture({ userConfig: existing });
+    try {
+      const before = await readFile(fixture.configPath, 'utf-8');
+      const result = await fixture.install();
+      assert.equal(result.code, 1);
+      assert.equal(await readFile(fixture.configPath, 'utf-8'), before);
+    } finally {
+      await fixture.close();
+    }
+  }
+});
+
+test('Copilot rejects missing runtimes before creating hook config', async () => {
+  const fixture = await createFixture({ createRuntimes: false });
+  try {
+    const result = await fixture.install();
+    assert.equal(result.code, 1);
+    assert.match(result.stderr, /runtime is missing/i);
+    await assert.rejects(readFile(fixture.configPath), { code: 'ENOENT' });
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('Copilot atomic writes leave no transaction files', async () => {
+  const fixture = await createFixture();
+  try {
+    assert.equal((await fixture.install()).code, 0);
+    const files = await readdir(path.dirname(fixture.configPath));
+    assert.equal(files.some((name) => name.endsWith('.tmp') || name.endsWith('.rollback')), false);
+  } finally {
+    await fixture.close();
+  }
+});