Expand an HL7 Value Set into Its Codes (FHIR Terminology Server)

fhirtx/expand-valueset

Expands an HL7 value set on the terminology server into its list of codes with system, code and display, optionally filtered by text and paged with count and offset. The url must be an HL7 value set (http://hl7.org/fhir/ValueSet/..., http://terminology.hl7.org/ValueSet/... or a LOINC value set). Up to 50 codes per call; the total is reported in expansion.total. A value set that expands from a restricted system is refused by the server or may return nothing. An unknown value set is refused as a validation error. HL7 FHIR terminology server data served by Eden Engine; not an official HL7 product.

activeper callv1

Price

$0.0026 per call

You pay the price shown. If a call turns out to cost more than its quote, you pay the actual price, capped at twice the quote. No monthly minimum. Top-ups start at $0.50.

Data source

HL7 FHIR Terminology Server (tx.fhir.org)

Source: HL7 FHIR Terminology Server (tx.fhir.org). Contains content from LOINC (http://loinc.org); LOINC is copyright Regenstrief Institute, Inc. and the LOINC Committee and is available under the license at http://loinc.org/license. Served by Eden Engine; not an official HL7 product.

Use it

Five steps: search, inspect, learn, run, settle. No per-tool setup; your agent reaches this tool through the meta-tools it already has.

Connect once and your AI can find and run this tool, and any other it needs.

Install it Create an account

agent

// 1. search: find the tool
omnial_search({ query: "what you need" })

// 2. inspect: price and input schema
omnial_inspect({ tool: "fhirtx/expand-valueset" })

// 3. learn: read the usage guide at runtime
omnial_learn({ tool: "fhirtx/expand-valueset" })

// 4. run: price the exact call first, then run it
omnial_execute({ tool: "fhirtx/expand-valueset", input: { /* see input_schema */ }, dry_run: true })
omnial_execute({ tool: "fhirtx/expand-valueset", input: { /* ... */ } })

// 5. settle: the call is charged when it finishes, nothing to do

Not connected yet? Point your MCP client at https://mcp.eden-engine.com/mcp, then copy a config for your client.

Pricing

Every charge this tool can incur.

Charge	Price
Per call	$0.0026

Updated: Oct 21, 2026

Input and output schemas

Input schema

input_schema.json

{
  "type": "object",
  "required": [
    "url"
  ],
  "properties": {
    "url": {
      "type": "string",
      "pattern": "^(http://(hl7\\.org/fhir|terminology\\.hl7\\.org)/ValueSet/[A-Za-z0-9._-]{1,100}|http://loinc\\.org/vs/[A-Za-z0-9._-]{1,40})$",
      "description": "Canonical URL of the value set, for example http://hl7.org/fhir/ValueSet/languages."
    },
    "count": {
      "type": "integer",
      "default": 20,
      "maximum": 50,
      "minimum": 1,
      "description": "Codes per call, 1 to 50. Defaults to 20."
    },
    "filter": {
      "type": "string",
      "maxLength": 100,
      "minLength": 1,
      "description": "Only codes whose display contains this text, for example french."
    },
    "offset": {
      "type": "integer",
      "maximum": 100000,
      "minimum": 0,
      "description": "Codes to skip, for paging."
    }
  },
  "additionalProperties": false
}

Output schema

output_schema.json

{
  "type": "object",
  "required": [
    "resourceType"
  ],
  "properties": {
    "url": {
      "type": "string"
    },
    "name": {
      "type": "string"
    },
    "title": {
      "type": "string"
    },
    "expansion": {
      "type": "object",
      "properties": {
        "total": {
          "type": "integer",
          "description": "Total codes in the value set (after the filter)."
        },
        "offset": {
          "type": "integer"
        },
        "contains": {
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "code": {
                "type": "string"
              },
              "system": {
                "type": "string"
              },
              "display": {
                "type": "string"
              }
            },
            "additionalProperties": true
          }
        }
      },
      "additionalProperties": true
    },
    "resourceType": {
      "type": "string"
    }
  },
  "description": "A FHIR ValueSet with its expansion.",
  "additionalProperties": true
}