# NousResearch/hermes-agent · Sanitize error headers containing control characters

## Open now

- 1 issue, 2 PRs open on GitHub.
- #133848: \[Bug\]: API server drops the connection when an agent error message contains a newline (X-Hermes-Error header)
- PR #133872: fix(api-server): fold control characters out of the X-Hermes-Error header
- PR #136580: fix(api-server): fold control characters out of _redact_api_error_text

A bug was identified where newline or other control characters in agent error messages corrupt HTTP response headers. Related fixes address sanitizing these characters in the API server and gateway error headers.

## TL;DR

- 4 member(s): 1 open issue(s), 0 closed issue(s), 2 open PR(s), 0 merged PR(s), 1 PR(s) closed without merging.
- No fix has been merged to main; one or more PRs were attempted (see below).
- **Recommended:** review the prior/competing PR(s) below. A fix was attempted but not merged; your case may extend or revive that work.

## Maintainer resolution verdict

- Internal-tracker verdict over this cluster's issue members: `unresolved`. 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evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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 `0.50`: 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.

## Open related issues

- #133848: \[Bug\]: API server drops the connection when an agent error message contains a newline (X-Hermes-Error header)

## Prior & competing PRs

- **#133872: fix(api-server): fold control characters out of the X-Hermes-Error header**. open
  - maintainer direction: category `silent_close`; implication `active`
  - files: `gateway/platforms/api_server_openai_routes.py`, `tests/gateway/test_api_server_error_header_newline.py`
- **#134317: fix(gateway): sanitize API error response headers**. closed without merge
  - maintainer direction: category `duplicate_of`; implication `duplicate`; refs `#133872`
- **#136580: fix(api-server): fold control characters out of _redact_api_error_text**. open
  - maintainer direction: category `uncategorized`; implication `needs_llm`
  - files: `gateway/platforms/api_server.py`, `tests/gateway/test_api_server.py`

## Fix status

- No merged fix on record.
- Subsystem: `gateway`