diff --git a/src/hooks/atlas/boulder-continuation-injector.test.ts b/src/hooks/atlas/boulder-continuation-injector.test.ts
index bb63d1c25..662a276e7 100644
--- a/src/hooks/atlas/boulder-continuation-injector.test.ts
+++ b/src/hooks/atlas/boulder-continuation-injector.test.ts
@@ -14,7 +14,7 @@ describe("injectBoulderContinuation", () => {
     _resetForTesting()
   })
 
-  test("normalizes config-key agent to display-name for promptAsync", async () => {
+  test("uses raw agent key for promptAsync to avoid HTTP header issues", async () => {
     // given
     registerAgentName("atlas")
     const promptAsyncMock = mock(async (_request: unknown) => undefined)
@@ -41,13 +41,19 @@ describe("injectBoulderContinuation", () => {
       sessionState: { promptFailureCount: 0 },
     })
 
+<<<<<<< HEAD
     // then
     expect(result).toBe("injected")
+||||||| parent of 1b39490a (fix(atlas): use raw agent key instead of display name for API calls (#3138))
+    // then
+=======
+    // then - uses raw agent key, not display name (to avoid HTTP header validation issues)
+>>>>>>> 1b39490a (fix(atlas): use raw agent key instead of display name for API calls (#3138))
     expect(promptAsyncMock).toHaveBeenCalledTimes(1)
     expect(promptAsyncMock).toHaveBeenCalledWith(
       expect.objectContaining({
         body: expect.objectContaining({
-          agent: "Atlas (Plan Executor)",
+          agent: "atlas",
         }),
       }),
     )
diff --git a/src/hooks/atlas/boulder-continuation-injector.ts b/src/hooks/atlas/boulder-continuation-injector.ts
index 48a6f1edc..ecb5c5663 100644
--- a/src/hooks/atlas/boulder-continuation-injector.ts
+++ b/src/hooks/atlas/boulder-continuation-injector.ts
@@ -1,7 +1,6 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import type { BackgroundManager } from "../../features/background-agent"
 import { isAgentRegistered } from "../../features/claude-code-session-state"
-import { normalizeAgentForPrompt } from "../../shared/agent-display-names"
 import { log } from "../../shared/logger"
 import { createInternalAgentTextPart, resolveInheritedPromptTools } from "../../shared"
 import { HOOK_NAME } from "./hook-name"
@@ -75,7 +74,7 @@ export async function injectBoulderContinuation(input: {
 		await ctx.client.session.promptAsync({
 			path: { id: sessionID },
 			body: {
-				agent: normalizeAgentForPrompt(continuationAgent) ?? continuationAgent,
+				agent: continuationAgent,
 				...(promptContext.model !== undefined ? { model: promptContext.model } : {}),
 				...(inheritedTools ? { tools: inheritedTools } : {}),
         parts: [createInternalAgentTextPart(prompt)],