diff --git a/__tests__/unit/explorer-search-parity.test.ts b/__tests__/unit/explorer-search-parity.test.ts
new file mode 100644
index 0000000..86e7088
--- /dev/null
+++ b/__tests__/unit/explorer-search-parity.test.ts
@@ -0,0 +1,123 @@
+/**
+ * Parity between SearchEngine.search and ExplorerService.explore under the
+ * same toolRules. Ensures callers can move between search and explore without
+ * observing different visible operation sets.
+ */
+
+import { describe, test, expect } from '@jest/globals';
+import { SearchEngine } from '../../packages/server/src/search/index';
+import { ExplorerService } from '../../packages/server/src/explorer/index';
+import { runInRequestScope } from '../../packages/server/src/core/request-scope';
+import type { APIGroupConfig, ClientToolRules } from '@mondaydotcomorg/atp-protocol';
+
+const stubFn = {
+	inputSchema: { type: 'object', properties: {}, required: [] },
+	handler: async () => ({}),
+};
+
+const apiGroups: APIGroupConfig[] = [
+	{
+		name: 'calendar',
+		type: 'custom',
+		functions: [
+			{ name: 'events_list', description: 'list events', ...stubFn },
+			{ name: 'events_get', description: 'get event', ...stubFn },
+			{ name: 'events_delete', description: 'delete event', ...stubFn },
+			{ name: 'events_insert', description: 'create event', ...stubFn },
+		],
+	},
+	{
+		name: 'gmail',
+		type: 'custom',
+		functions: [
+			{ name: 'messages_list', description: 'list messages', ...stubFn },
+			{ name: 'messages_send', description: 'send message', ...stubFn },
+		],
+	},
+];
+
+/** Flatten search results → Set of `${group}.${fn}` */
+async function searchVisible(engine: SearchEngine): Promise<Set<string>> {
+	// A permissive query that matches every function description so the rule
+	// set — not the query — determines the visible set.
+	const all = new Set<string>();
+	for (const q of ['list', 'get', 'delete', 'send', 'create', 'message', 'event']) {
+		const results = await engine.search({ query: q, maxResults: 1000 });
+		for (const r of results) all.add(`${r.apiGroup}.${r.functionName}`);
+	}
+	return all;
+}
+
+/** Walk explore at every (group, functionName) → Set of `${group}.${fn}` visible. */
+function exploreVisible(explorer: ExplorerService): Set<string> {
+	const visible = new Set<string>();
+	const root = explorer.explore('/custom');
+	if (!root || root.type !== 'directory') return visible;
+	for (const groupItem of root.items) {
+		if (groupItem.type !== 'directory') continue;
+		const groupResult = explorer.explore(`/custom/${groupItem.name}`);
+		if (!groupResult || groupResult.type !== 'directory') continue;
+		for (const fnItem of groupResult.items) {
+			if (fnItem.type === 'function') visible.add(`${groupItem.name}.${fnItem.name}`);
+		}
+	}
+	return visible;
+}
+
+function parityUnder<T>(rules: ClientToolRules | undefined, fn: () => T): T {
+	if (!rules) return fn();
+	return runInRequestScope({ toolRules: rules }, fn) as T;
+}
+
+describe('ExplorerService / SearchEngine tool-rule parity', () => {
+	const search = new SearchEngine(apiGroups);
+	const explorer = new ExplorerService(apiGroups);
+
+	test('no rules: both surface every function', async () => {
+		const s = await parityUnder(undefined, () => searchVisible(search));
+		const e = parityUnder(undefined, () => exploreVisible(explorer));
+		expect(e).toEqual(s);
+		// Sanity: the full 6-op set is visible.
+		expect(s.size).toBe(6);
+	});
+
+	test('allowOnlyApiGroups=[calendar]: both hide gmail entirely', async () => {
+		const rules: ClientToolRules = { allowOnlyApiGroups: ['calendar'] };
+		const s = await parityUnder(rules, () => searchVisible(search));
+		const e = parityUnder(rules, () => exploreVisible(explorer));
+		expect(e).toEqual(s);
+		for (const fn of s) expect(fn.startsWith('calendar.')).toBe(true);
+	});
+
+	test('allowOnlyTools (per-op allowlist): both narrow to the exact ops', async () => {
+		const rules: ClientToolRules = {
+			allowOnlyTools: ['calendar.events_list', 'calendar.events_get'],
+		};
+		const s = await parityUnder(rules, () => searchVisible(search));
+		const e = parityUnder(rules, () => exploreVisible(explorer));
+		expect(e).toEqual(s);
+		expect(e).toEqual(new Set(['calendar.events_list', 'calendar.events_get']));
+	});
+
+	test('blockTools (per-op denylist): both drop the blocked ops', async () => {
+		const rules: ClientToolRules = {
+			blockTools: ['calendar.events_delete', 'calendar.events_insert'],
+		};
+		const s = await parityUnder(rules, () => searchVisible(search));
+		const e = parityUnder(rules, () => exploreVisible(explorer));
+		expect(e).toEqual(s);
+		expect(e.has('calendar.events_delete')).toBe(false);
+		expect(e.has('calendar.events_insert')).toBe(false);
+		expect(e.has('calendar.events_list')).toBe(true);
+	});
+
+	test('empty allowOnlyApiGroups: both surface nothing (fail-closed)', async () => {
+		const rules: ClientToolRules = { allowOnlyApiGroups: [] };
+		// Empty array in allowOnlyApiGroups is treated as "no restriction" by
+		// isGroupAllowed (line: `if (rules.allowOnlyApiGroups && rules.allowOnlyApiGroups.length > 0)`),
+		// so both should see every function. Documenting that parity explicitly.
+		const s = await parityUnder(rules, () => searchVisible(search));
+		const e = parityUnder(rules, () => exploreVisible(explorer));
+		expect(e).toEqual(s);
+	});
+});
diff --git a/packages/server/src/explorer/index.ts b/packages/server/src/explorer/index.ts
index cba49b6..04dd9c4 100644
--- a/packages/server/src/explorer/index.ts
+++ b/packages/server/src/explorer/index.ts
@@ -81,8 +81,10 @@ export class ExplorerService {
 			context.allowedGroups.add(group.name);
 		}
 
-		for (const group of this.apiGroups) {
-			if (!context.allowedGroups.has(group.name)) continue;
+		// Iterate already-filtered `allowedGroups` so per-tool rules
+		// filter operations WITHIN an allowed group (matches the pattern
+		// in `SearchEngine.search`).
+		for (const group of allowedGroups) {
 			if (group.functions) {
 				for (const func of group.functions) {
 					context.allowedTools.add(`${group.name}:${func.name}`);
diff --git a/packages/server/src/handlers/execute.handler.ts b/packages/server/src/handlers/execute.handler.ts
index 10962f8..bd0d097 100644
--- a/packages/server/src/handlers/execute.handler.ts
+++ b/packages/server/src/handlers/execute.handler.ts
@@ -122,7 +122,13 @@ export async function handleExecute(
 		provenanceHints: requestConfig.provenanceHints,
 		requestContext: {
 			...requestConfig.requestContext,
-			headers: ctx.headers,
+			// Merge caller-supplied headers with ctx.headers; ctx wins on
+			// conflicts so session auth takes precedence over app-layer keys.
+			headers: {
+				...(requestConfig.requestContext as { headers?: Record<string, string> } | undefined)
+					?.headers,
+				...ctx.headers,
+			},
 			path: ctx.path,
 			method: ctx.method,
 		},