turnId: string;

}): Promise<void> {

try {

const messages = await resolveFinalCodexMirrorMessages({

params: params.params,

messagesSnapshot: params.result.messagesSnapshot,

turnId: params.turnId,

});

const mirrorResult = await mirrorCodexAppServerTranscript({

sessionFile: params.params.sessionFile,

agentId: params.agentId,

sessionKey: params.sessionKey,

messages: params.result.messagesSnapshot,

messages,

// Scope is thread-stable. Each entry in `messagesSnapshot` is tagged

// with a per-turn `attachCodexMirrorIdentity` value carrying its own

// turnId, so distinct turns produce distinct dedupe keys via the

}

}

async function resolveFinalCodexMirrorMessages(params: {

params: EmbeddedRunAttemptParams;

messagesSnapshot: AgentMessage[];

turnId: string;

}): Promise<AgentMessage[]> {

if (

params.params.suppressNextUserMessagePersistence ||

!params.params.userTurnTranscriptRecorder

) {

return params.messagesSnapshot;

}

const resolvedPrompt = attachCodexMirrorIdentity(

await buildResolvedCodexUserPromptMessage(params.params),

`${params.turnId}:prompt`,

);

const firstUserIndex = params.messagesSnapshot.findIndex((message) => message.role === "user");

if (firstUserIndex === -1) {

return [resolvedPrompt, ...params.messagesSnapshot];

}

const messages = params.messagesSnapshot.slice();

messages[firstUserIndex] = resolvedPrompt;

return messages;

}

function createCodexAppServerUserMessagePersistenceNotifier(

runParams: EmbeddedRunAttemptParams,

): (message: Extract<AgentMessage, { role: "user" }>) => void {