# NousResearch/hermes-agent · CORS headers missing on SSE stream endpoints

## Open now

- Nothing open on GitHub.

These members address missing CORS headers on server-sent event (SSE) stream responses in the API server, specifically affecting session chat stream endpoints. The work involves identifying the root cause and applying fixes to ensure CORS headers are consistently included on SSE responses.

## TL;DR

- 3 member(s): 0 open issue(s), 1 closed issue(s), 0 open PR(s), 1 merged PR(s), 1 PR(s) closed without merging.
- A fix was merged to main in PR #121745. Verify it addresses your case.
- **Recommended:** read PR #121745 (and any competing PRs below) before filing. Confirm the merged change covers your symptom.

## Maintainer resolution verdict

- Internal-tracker verdict over this cluster's issue members: `resolved` · deciding PR(s): `pr-121745`. This is distinct from the fix status above. Weigh it yourself.

## How this cluster was grouped

- Link evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
- Pairwise link density `0.67`: the share of member pairs that carry a link, counting a structural link in full and a relevance-only link at 0.36. `1.00` means every pair is linked.

## Closed / duplicate issues

- #72892: \[Bug\]: POST /api/sessions/{id}/chat/stream missing CORS headers — same root cause as #6358, different call site

## Prior & competing PRs

- **#121745: fix(api-server): CORS on every SSE stream, flush run-events head, report failed tools as tool.failed**. merged to main · fix tier `verified`
  - maintainer direction: category `merged`
  - files: `contributors/emails/195337306+0xGr1mm@users.noreply.github.com`, `gateway/platforms/api_server.py`, `gateway/platforms/api_server_openai_routes.py`, `gateway/platforms/api_server_runs.py`, `tests/gateway/test_api_server.py`, `tests/gateway/test_api_server_runs.py`, `tests/gateway/test_session_api.py`, `website/docs/user-guide/features/api-server.md`
- **#72945: fix(api-server): resolve CORS headers on session chat stream SSE response (#72892)**. closed without merge
  - maintainer direction: category `implemented_elsewhere`; implication `superseded`; refs `346c14a9c5`, `#121745`, `#72892`

## Fix status

- Merged to main in PR #121745 (cited above). No release data is tracked. Verify downstream.
- Fix last verified (merged) `2026-09-25`.
- Subsystem: `gateway`