`search_thoughts` fails when pgvector is installed in `extensions` schema

[alcohen]

Which contribution?

core

What happened?

search_thoughts fails on every call with:

Search error: operator does not exist: extensions.vector <=> extensions.vector

capture_thought, list_thoughts, and thought_stats work normally.

Root cause: Supabase installs pgvector in the extensions schema on some project configurations. The match_thoughts function has search_path=public hardcoded, so it can't see the <=> operator from extensions.vector.

Confirmed via:
SELECT proname, proconfig FROM pg_proc WHERE proname = 'match_thoughts';
-- returns search_path=public

SELECT nspname, extname FROM pg_extension e JOIN pg_namespace n ON e.extnamespace = n.oid WHERE extname = 'vector';
-- returns extensions

What I tried
ALTER EXTENSION vector SET SCHEMA public — the error changes to type "extensions.vector" does not exist, suggesting the Edge Function or RPC call also has a hardcoded extensions.vector type reference. Reverting with ALTER EXTENSION vector SET SCHEMA extensions restores the original error state.

What did you expect?

Search_thoughts returns results. Possiblefix: set search_path=public,extensions on match_thoughts, or explicitly install pgvector in public during setup (CREATE EXTENSION vector SCHEMA public).

Steps to reproduce

1. Create a new Supabase project (pgvector lands in extensions schema by default on some configurations)
2. Follow the standard OB1 setup — run the schema SQL, deploy the edge function
3. Capture a few thoughts via capture_thought
4. Call search_thoughts with any query
5. Observe: operator does not exist: extensions.vector <=> extensions.vector

Environment

• Self-hosted OB1 on Supabase
• pgvector installed in extensions schema (Supabase default on some project configurations)

[github-actions]

Hey @alcohen — welcome to Open Brain Source! 👋

Thanks for opening your first issue. Someone from the community will take a look soon.

If you're interested in contributing (code or not), check out CONTRIBUTING.md — we have paths for developers and non-developers alike.

[alcohen]

Root cause confirmed. On my install match_thoughts had SET search_path = public, but pgvector — and its <=> cosine operator — is in the extensions schema, so the operator couldn't resolve (hence operator does not exist: extensions.vector <=> extensions.vector). The other thought tools were unaffected since only search uses the vector operator.

Fix that works without moving the extension (moving it to public just swaps the error for type "extensions.vector" does not exist, since the type is referenced schema-qualified):

ALTER FUNCTION public.match_thoughts(extensions.vector, double precision, integer, jsonb)
  SET search_path = public, extensions;

Note that current main's match_thoughts (in docs/01-getting-started.md) doesn't pin search_path at all, so a fresh install inherits the session path and won't hit this. So it seems limited to setups whose function was pinned to public (older setup SQL, or a search_path-hardening step). Likely safe to close — though adding a defensive SET search_path = public, extensions to the documented function would harden it against anyone who later pins the path. Thanks!