bug: URL-based chat seeding (`send-on-load` / `submit-on-load`) ignores `agentId`, ignores `user-prompt`, and misparses booleans

[blambert]

Summary

Deep-linking into the chat app with query params to pre-seed and auto-send a prompt is broken in three distinct ways. All three live in web/src/views/AppPage.tsx, web/src/hooks/useChatSessionController.ts, and web/src/app/app/services/searchParams.ts.

Environment

• Deployment: self-hosted 4.4.7
• Branch/commit: main
• Browser: Chrome Stable

Reproduction

https://onyx.example.org/app?agentId=8&user-prompt=Example%20prompt&send-on-load=true
https://onyx.example.org/app?agentId=8&user-prompt=Example%20prompt&submit-on-load=true
https://onyx.example.org/app?agentId=8&user-prompt=Example%20prompt&send-on-load=false

Expected vs. Actual

#	Scenario	Expected	Actual
1	send-on-load=true + agentId=8	Prompt sent as agent 8	Sent as default persona
2	submit-on-load=true + agentId=8	Prompt sent as agent 8, prompt visible in user bubble	Sent as default persona and user bubble is empty
3	send-on-load=false	Nothing auto-sends	Prompt auto-sends anyway

---

Root causes

3 — send-on-load is truthiness-checked, not parsed

// web/src/views/AppPage.tsx
useEffect(() => {
  if (searchParams?.get(SEARCH_PARAM_NAMES.SEND_ON_LOAD)) {
    processSearchParamsAndSubmitMessage(searchParams.toString());
  }
}, [searchParams, router]);

searchParams.get() returns the string "false", which is truthy [1]. A correct parser already exists in the codebase and simply isn't used here:

// web/src/app/app/services/searchParams.ts
export function shouldSubmitOnLoad(searchParams) {
  const raw = searchParams?.get(SEARCH_PARAM_NAMES.SUBMIT_ON_LOAD);
  return raw === "true" || raw === "1";
}

[2] — note it only covers SUBMIT_ON_LOAD. SEND_ON_LOAD has no equivalent.

2 — submit-on-load submits firstMessage, not user-prompt

// web/src/app/app/page.tsx
const firstMessage = searchParams.firstMessage;
return <AppPage firstMessage={firstMessage} />;

// web/src/hooks/useChatSessionController.ts — initialSessionFetch()
setSelectedAgentFromId(null);                       // ← agent reset to default
...
if (shouldSubmitOnLoad(searchParams) && !submitOnLoadPerformed.current) {
  submitOnLoadPerformed.current = true;
  await onSubmit({
    message: firstMessage || "",                    // ← user-prompt never read
    currentMessageFiles: [],
    deepResearch: false,
  });
}

[3]

Two bugs in one block:

• The message comes from a different, undocumented param (firstMessage), so user-prompt is dropped and an empty string is submitted → blank user bubble.
• setSelectedAgentFromId(null) runs immediately before, actively clearing any agent selection before the send.

1 — send-on-load never reads agentId

processSearchParamsAndSubmitMessage reads user-prompt, builds filters, deletes SEND_ON_LOAD, and calls onSubmit — it never touches agentId [1]. Agent resolution is a separate async path (useAgentController → useAgents() SWR), and useChatController creates the session with liveAgent?.id || 0. On a cold load the effect fires while agents is still loading, so the session is bound to persona 0 before agentId=8 ever resolves. The effect's dependency array is [searchParams, router] — no gate on isLoadingAgents [1].

---

Suggested fixes

Consider consolidating send-on-load and submit-on-load. Two params doing nearly the same thing through two different code paths is very likely how this divergence happened — deprecate one, alias it to the other.

1. Gate auto-submit on agent readiness. Don't fire until !isLoadingAgents, and ideally until liveAgent?.id === Number(searchParams.get("agentId")).
2. Pass agentId explicitly through the submit path rather than relying on liveAgent having resolved — e.g. const personaId = liveAgent?.id ?? agentIdFromParams ?? DEFAULT_AGENT_ID.
3. Don't call setSelectedAgentFromId(null) on the submit-on-load path when agentId is present in the URL.
4. Read user-prompt in the submit-on-load path, or at minimum fall back: firstMessage || searchParams.get(SEARCH_PARAM_NAMES.USER_PROMPT).
5. Use shouldSubmitOnLoad-style parsing for SEND_ON_LOAD (=== "true" || === "1").