diff --git a/src/agent/subagents/pi-run.ts b/src/agent/subagents/pi-run.ts
index 890fe04..458bc29 100644
--- a/src/agent/subagents/pi-run.ts
+++ b/src/agent/subagents/pi-run.ts
@@ -1,6 +1,6 @@
 import { Agent, type AgentEvent, type AgentMessage, type AgentTool } from "@earendil-works/pi-agent-core";
 import type { AssistantMessage, ToolResultMessage, Usage } from "@earendil-works/pi-ai";
-import { openRouterApiKey, piEngineFor, type PiEngine } from "../models.ts";
+import { piEngineFor, type PiEngine } from "../models.ts";
 import type { ModelRole } from "../../../config.ts";
 
 /**
@@ -65,7 +65,6 @@ export async function runSubagent(tools: AgentTool<any, any>[], opts: SubagentRu
 			messages: opts.messages ?? [],
 		},
 		streamFn: engine.streamFn,
-		getApiKey: () => openRouterApiKey(),
 		shouldStopAfterTurn: (context) => {
 			turns++;
 			return turns >= opts.maxTurns || opts.shouldStop?.(context.message, context.toolResults) === true;
diff --git a/src/agent/teacher-agent.ts b/src/agent/teacher-agent.ts
index 335e2d3..853e400 100644
--- a/src/agent/teacher-agent.ts
+++ b/src/agent/teacher-agent.ts
@@ -2,7 +2,7 @@ import { Agent } from "@earendil-works/pi-agent-core";
 import type { AgentEvent, AgentMessage, AgentTool } from "@earendil-works/pi-agent-core";
 import type { Usage } from "@earendil-works/pi-ai";
 import { PATHS } from "../../config.ts";
-import { piEngineFor, openRouterApiKey, type PiEngine } from "./models.ts";
+import { piEngineFor, type PiEngine } from "./models.ts";
 import { effectivePromptSegments } from "./prompt-segments.ts";
 import {
 	askUserQuestionTool,
@@ -158,7 +158,6 @@ function baseAgentOptions(kind: AgentKind, opts: AgentBuildOptions, tools: Agent
 			messages: opts.messages ?? [],
 		},
 		streamFn: engine.streamFn,
-		getApiKey: () => openRouterApiKey(),
 		shouldStopAfterTurn: stopper,
 	});
 	if (opts.onUsage) {
diff --git a/tests/api-key-hook.test.ts b/tests/api-key-hook.test.ts
new file mode 100644
index 0000000..181961c
--- /dev/null
+++ b/tests/api-key-hook.test.ts
@@ -0,0 +1,55 @@
+/**
+ * The getApiKey-hook fix (owner, 2026-09-26): both Agent constructions
+ * (baseAgentOptions in teacher-agent.ts, runSubagent's loop in
+ * subagents/pi-run.ts) used to pass `getApiKey: () => openRouterApiKey()` —
+ * and pi-agent-core resolves
+ * `(config.getApiKey ? await config.getApiKey(provider) : undefined) || config.apiKey`
+ * (agent-loop.js:191), so a provided hook OVERRIDES pi-ai's native
+ * per-provider env resolution. The hook ignored its provider arg, so every
+ * non-OpenRouter provider was sent the OpenRouter key and 401'd (owner repro:
+ * openai:gpt-5.6-luna, anthropic:claude-haiku-4-5 direct).
+ *
+ * The fix is DELETION: with no hook, pi-ai resolves keys natively from the
+ * environment per request — the architecture's stated intent (models.ts:
+ * "the keys seam reflects file-saved keys into env"). This file pins that
+ * the deletion holds: the built agents must expose NO getApiKey hook, so
+ * native resolution runs for every provider.
+ *
+ * runSubagent's Agent is internal to its promise (no exposed seam); its
+ * hook was deleted in the same commit and its behavior is covered by the
+ * sub-agent suite's faux engines.
+ */
+
+import assert from "node:assert/strict";
+import { describe, it } from "node:test";
+import { createProberAgent, createTeacherAgent, type TeachingAgent } from "../src/agent/teacher-agent.ts";
+import type { ProberToolContext } from "../src/agent/tools.ts";
+import { jobStore } from "../src/store/jobs.ts";
+import { chatStore } from "../src/store/chats.ts";
+import { createFauxCore } from "@earendil-works/pi-ai";
+import type { PiEngine } from "../src/agent/models.ts";
+
+/** A scripted pi engine — the agent builds need an injected engine since
+ * BYOK removed the factory pins (owner, 2026-09-22). */
+function fauxEngine(): PiEngine {
+	const faux = createFauxCore({});
+	return { model: faux.getModel(), streamFn: faux.streamSimple };
+}
+
+describe("the getApiKey-hook fix (native per-provider key resolution)", () => {
+	it("teacher and prober builds expose NO getApiKey hook — pi-ai resolves keys natively", () => {
+		const chatId = chatStore.createChat("getApiKey pin").id;
+		const ctx: ProberToolContext = { chatId, chatStore, deliver: () => {}, jobStore, spawn: () => {} };
+		const builds: TeachingAgent[] = [
+			createTeacherAgent(undefined, { engine: fauxEngine() }),
+			createProberAgent(ctx, { engine: fauxEngine() }),
+		];
+		for (const agent of builds) {
+			assert.equal(
+				(agent as unknown as { getApiKey?: unknown }).getApiKey,
+				undefined,
+				"the OpenRouter-pinning hook must stay deleted — a set hook overrides pi-ai's native per-provider env resolution for EVERY provider",
+			);
+		}
+	});
+});
\ No newline at end of file