Last EHR — Medplum MCP server

Last EHR

Read the chart broadly. Write only what a human approved. Last EHR is the agent layer for a headless FHIR EHR. It does three things, and the write protocol is only one of them.

It reads the chart broadly. 25 of US Core 9.0.0's 27 readable resource types, across 23 patient-scoped sections, following references so authors, encounters, and provenance stop being dead pointers. Counted in the open, with the ceiling published rather than implied, in FHIR coverage.

It is built so the agent cannot fake an absence. "She has never had a flu shot" is the answer a chart agent must never invent, so a read reports when its window was capped, when a reference lookup was refused, and when a code filter matched nothing in a section that does hold records. Filters that a section cannot apply are refused with the legal values instead of silently dropped. These are safety-boundary tests, not best-effort behavior.

Every write is a proposal. Show the exact resource, require an explicit human decision, commit exactly what was reviewed, and record what created it. That half is a small protocol, Approval-Gated Agent Writes on FHIR (v0.1 draft): Proposal → Decision → Commit → Audit. Two implementations run here, a web approval card and MCP elicitation-gated write tools, plus a conformance suite that checks implementations with its own FHIR reads. Independent implementations and criticism are invited.

Five FHIR backends sit behind one interface. This repository is the reference implementation: bring your own FHIR backend and model key for a real agent (Medplum for the authenticated path, or any verified adapter for synthetic evaluation), or start with the zero-key local synthetic walkthrough.

Last EHR is a layer, not an EHR. It runs on top of a headless FHIR backend (Medplum for authenticated use; HAPI FHIR, Firely Server, Aidbox, or Oystehr for synthetic evaluation) and talks to it over the FHIR API. It is not the system of record, stores no PHI of its own, and never bundles or forks the backend.

Status: early / alpha. APIs, structure, and scope will change. Use synthetic data only. · License: Apache-2.0

Try the live demo: no sign-up, synthetic data, and every write goes through the approval gate.

Start here

Shortened. The full README is on GitHub.