# NousResearch/hermes-agent · $ref pointer breakage from nullable anyOf collapsing

## Open now

- 1 issue, 2 PRs open on GitHub.
- #67131: xAI Responses 400: unresolvable $ref after strip_nullable_unions collapses anyOf (MCP/Zod/Paperclip)
- PR #67266: fix: inline combinator-path $refs before strip_nullable_unions (#67131)
- PR #67423: fix(schema): rewrite $ref pointers after collapsing nullable anyOf

These members concern a bug where stripping nullable unions collapses anyOf schemas in a way that leaves unresolvable $ref pointers. The group includes a bug report and two fix attempts targeting the rewriting or inlining of $refs around this transformation.

## TL;DR

- 3 member(s): 1 open issue(s), 0 closed issue(s), 2 open PR(s), 0 merged PR(s), 0 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evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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 `0.67`: 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.

## Open related issues

- #67131: xAI Responses 400: unresolvable $ref after strip_nullable_unions collapses anyOf (MCP/Zod/Paperclip)

## Prior & competing PRs

- **#67266: fix: inline combinator-path $refs before strip_nullable_unions (#67131)**. open
  - maintainer direction: category `uncategorized`; implication `needs_llm`
  - files: `tests/tools/test_schema_sanitizer.py`, `tools/schema_sanitizer.py`
- **#67423: fix(schema): rewrite $ref pointers after collapsing nullable anyOf**. open
  - maintainer direction: category `partial_fix`; implication `needs_llm`; refs `d84b5f9faf70`, `#67131`, `#67137`, `#67266`, `#67423`, `#374151`
  - files: `agent/anthropic_adapter.py`, `tools/mcp_tool.py`, `tools/schema_sanitizer.py`

## Fix status

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