---
summary: "interactions target source, per-kind isolation, fetch resilience for image and 3D structure"
breaking: false
security: false
---

# 0.2.1 — 2026-06-02

## Fixed

- **`pubchem_get_compound_interactions` (`target` kind)** — now returns chemical–target binding and activity for the requested compound, sourced from PubChem's CID-keyed `bioactivity` collection (BindingDB, ChEMBL, and others). Previously queried a gene-indexed collection whose compound filter was silently ignored, causing every compound to return the same unrelated compound's records ([#20](https://github.com/cyanheads/pubchem-mcp-server/issues/20)).
- **`pubchem_get_compound_interactions` (per-kind isolation)** — a failure in one requested interaction kind no longer discards the kinds that succeeded. Successful kinds are returned and unavailable kinds are reported via a `failedKinds` notice (`Promise.allSettled` per-kind isolation) ([#21](https://github.com/cyanheads/pubchem-mcp-server/issues/21)).
- **`pubchem_get_compound_image` and `pubchem_get_compound_3d_structure`** — image and 3D-structure fetches now retry once on transient upstream 5xx errors and surface a clear `PubChem request timed out (30s)` message on timeout instead of a raw abort error, matching the JSON fetch path ([#16](https://github.com/cyanheads/pubchem-mcp-server/issues/16)).
- **SDQ-backed interaction fetches** — PubChem's occasional malformed JSON now returns a contextful error instead of an opaque `Failed to parse JSON`.