# Openapi Adapter

> External-adapter sub-skill; turns an OpenAPI operation into a sealed tool result.

- Skill: `runxhq/openapi-adapter` (Agent Skill, multi-file: 5 files)
- Install (CLI): `npx skillmds@latest add runxhq/openapi-adapter`
- Raw SKILL.md: https://api.skillmd.com/api/skills/runxhq/openapi-adapter/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: runxhq (https://skillmd.com/u/runxhq)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/runxhq/openapi-adapter

---

An OpenAPI front, expressed as an external adapter. The adapter reads a
checked-in OpenAPI spec (`openapi.json`), resolves the requested operation,
validates parameters against the spec, performs the adapter-owned HTTP call, and seals
the response. The network leg lives on the adapter, the supervised side of the
boundary; when the endpoint is unreachable (the bare harness, no fixture server)
it falls back to the resolved request so the example still runs offline. This
proves the governed core runs from an external spec, not only from MCP: the same
`external-adapter` lane carries any protocol.

`examples/openapi-graph/run.sh` starts a local fixture endpoint and shows the real
response sealed into the receipt. external-adapter is a graph-step front, not a
top-level runner.