# FHIR API Termbox supports all R4, R5, and R6 normative operations on ValueSets and CodeSystems[^4] {% hint style="info" %} **Support Legend** - ✅ Full support - Complete implementation with all parameters - 🏗️ In development - Under development, expect partial support in the meantime - ❌ No support - In our roadmap - 🚫 Won't support - Not in our roadmap {% endhint %} ## Operations
| Operation | Description | Support | | --------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | | `CodeSystem/$lookup` | Given a code/system, get additional details about the concept. See [docs](https://www.hl7.org/fhir/codesystem-operation-lookup.html) | ✅ | | `CodeSystem/$validate-code` | Validates a coded value. See [docs](https://www.hl7.org/fhir/codesystem-operation-validate-code.html) | ✅ | | `CodeSystem/$subsumes` | Test the subsumption relationship between A and B. See [docs](https://www.hl7.org/fhir/codesystem-operation-subsumes.html) | ✅ | | `CodeSystem/$find-matches` | Given a set of properties (and text), return one or more possible matching codes. See [docs](https://www.hl7.org/fhir/codesystem-operation-find-matches.html). Supported via [`$x-multi-invoke`](#x-multi-invoke). | ✅ | | `ValueSet/$expand` | Returns an expansion of concepts according to the value set definition. See [docs](https://www.hl7.org/fhir/valueset-operation-expand.html) | ✅ | | `ValueSet/$validate-code` | Validate that a coded value is in the set of codes allowed by a value set. See [docs](https://www.hl7.org/fhir/valueset-operation-validate-code.html) | ✅ | | `ConceptMap/$translate` | Translate a code from one terminology to another. See [docs](https://www.hl7.org/fhir/conceptmap-operation-translate.html) | ✅ | | `ConceptMap/$closure` | Maintenance of a client-side transitive closure table. See [docs](https://www.hl7.org/fhir/conceptmap-operation-closure.html) | ❌ | | `/$x-multi-invoke` | Termbox extension: invoke a supported operation over multiple entries in a single request. See [`$x-multi-invoke`](#x-multi-invoke). | ✅ |
## Features | Feature | Description | Support | | -------------------------------------------- | --------------------------------------------------------------- | ------- | | Capability Statements | + TerminologyCapabilities | ✅ | | CRUD of Terminology resources | Create, Read, Update, Delete operations | 🏗️ | | Pre-coordinated codes | Standard coded concepts | ✅ | | Post-coordinated codes | Complex expressions not yet supported | ❌ | | Intensional ValueSets | Filter-based ValueSet definitions | ✅ | | Extensional ValueSets | Explicit concept enumeration | ✅ | | ValueSet expansion | Full expansion with pagination | ✅ | | ValueSet validation | Code membership validation | ✅ | | ValueSet inclusion/exclusion | Deep set operations support | ✅ | | Lookup displays, designation, and properties | All concept attributes | ✅ | | Full text search filter | Prefix, stemming, phrase matching | ✅ | | FTS ranking | Full text search ranking based on relevance | ✅ | | Property filters | Property-based filtering: `=`, `in`, `regex`, etc | ✅ | | Subsumption filtering | `is-a`, `generalizes`, `ancestors`, etc | ✅ | | Active/Inactive filtering | Via `status`, `inactive`, `notSelectable`, etc | ✅ | | Multi-language support | Translations via displaylanguage, HTTP header, designation, etc | ✅ | | Hierarchy via properties | e.g.: `parent`, `child`, `PAR`, `CHD`, etc | ✅ | | Nested concepts | Hierarchy via `concept.concept` | ✅ | | Supplemental CodeSystems | Additional concept properties and designations | 🏗️ | | Implicit ValueSets | System-generated ValueSets | ✅ | | ConceptMap translations | Code mapping between terminology systems | ✅ | | Multiple ConceptMap matches | Returns all applicable mappings for source code | ✅ | | Transitive closure table | `$closure` | ❌ | | Syntax-based code systems | UCUM, BCP-47, HGVS, etc | ❌ | | `tx-resource` parameter | Inline resource definitions | ✅ | | Ad-hoc ValueSets | ValueSet as a `Parameter` | ✅ | | R4/R5/R6 format conversion | One server, one database, multiple FHIR versions | ❌ | | Batch validation | Validation of many codes in one request | 🏗️ | ## Extension Operations ### $x-multi-invoke `POST /fhir/$x-multi-invoke` Invokes a FHIR operation over multiple entries in a single request. This operation allows for high-throughput batch invocation of supported operations. **Supported operations** | `operation` value | Description | | -------------------------- | ----------------------------------------------------------------- | | `CodeSystem/$find-matches` | Match each entry's display text against concepts in a CodeSystem. | **Request parameters** The request body is a FHIR `Parameters` resource with the following parameters: | Name | Type | Description | | ----------- | -------- | -------------------------------------------------------------------------------------------------------------- | | `operation` | `uri` | The operation to invoke, e.g. `CodeSystem/$find-matches`. | | `shared` | `part` | Parameters shared across all entries. Parts: `system` (uri, required), `version` (string, optional). | | `entry` | `part[]` | One entry per lookup. Parts: `display` (string, required), `system` (uri, optional), `version` (string, optional). Entry-level `system` / `version` overrides the shared values. | **Response** Returns a `Parameters` resource with one `entry` per input entry (in the same order). Each `entry.part` contains zero or more `match` elements. An entry with no matching concept returns an empty `part` array. **Example** {% tabs %} {% tab title="Request" %} ```http POST /fhir/$x-multi-invoke Content-Type: application/json { "resourceType": "Parameters", "parameter": [ { "name": "operation", "valueUri": "CodeSystem/$find-matches" }, { "name": "shared", "part": [ { "name": "system", "valueUri": "http://snomed.info/sct" }, { "name": "version", "valueString": "http://snomed.info/sct/83821000000107/version/20260211" } ] }, { "name": "entry", "part": [{ "name": "display", "valueString": "Acute appendicitis" }] }, { "name": "entry", "part": [{ "name": "display", "valueString": "Type 2 diabetes mellitus" }] }, { "name": "entry", "part": [{ "name": "display", "valueString": "this description does not exist" }] } ] } ``` {% endtab %} {% tab title="Response" %} ```json { "resourceType": "Parameters", "parameter": [ { "name": "entry", "part": [ { "name": "match", "part": [{ "name": "code", "valueCode": "85189001" }] } ] }, { "name": "entry", "part": [ { "name": "match", "part": [{ "name": "code", "valueCode": "44054006" }] } ] }, { "name": "entry", "part": [] } ] } ``` {% endtab %} {% endtabs %} {% hint style="info" %} Matching is exact and case-sensitive. Per-entry `system` and `version` parts can be used to look up across different code systems in a single request. {% endhint %} ## FHIR Versions Termbox runs one endpoint for each major FHIR version[^5] and a default endpoint (currently R5, users will be able to configure this in upcoming releases) - Default: `/fhir/` - Version specific: `/fhir/:version/` Examples: - R6: `GET /fhir/r6/ValueSet/$expand` - R4B: `GET /fhir/r4b/metadata`