API Reference
Batch code lookup
Look up multiple medical codes in a single request.
Endpoint: POST /api/v1/codes/batch
Availability: Live in production.
Authentication: API key in Authorization: Bearer <key> with the read scope.
Look up multiple medical codes in a single request. Returns results keyed by code. Maximum 50 codes per request. Fuzzy matching is disabled in batch mode for performance.
Partial failure handling: Individual code lookup failures do not abort the batch. A code that cannot be resolved returns {"found": false, "code": "<code>", "code_system": "UNKNOWN"} in the results map instead of causing a request-level error, even when the request includes a code_system hint.
Parameters
codes(body, required): Array of medical codes to look upcode_system(body): Optional code system hint applied to all codesinclude(body): Comma-separated list of additional data (rvu, policies)
Code sources: Code entries in the response carry a source: document when the policy document lists the code, inferred_title_match when the code was attached because the policy title names the drug. See Code sources.
Example request
curl -X POST "https://backworkhealth.com/api/v1/codes/batch" \
-H "Authorization: Bearer $BACKWORK_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"codes": [
"99213",
"E11.9",
"27447"
]
}'Example response (200)
{
"success": true,
"data": {
"results": {}
},
"meta": {
"request_id": "string",
"timestamp": "2026-01-15T10:30:00Z",
"total_codes": 0,
"unique_codes": 0,
"includes": [
"string"
],
"attributions": {
"disclaimer": "string",
"cpt": "string",
"loinc": "string",
"cms": "string",
"payer_data": "string",
"negotiated_rates": "string"
}
}
}Authorization
bearerAuth AuthorizationBearer <token>
API key in format: bwk_live_xxxxx. Keys issued before the rename (vrt_live_) remain valid. bwk_test_ keys work only on the sandbox.
In: header
Request Body
application/json
TypeScript Definitions
Use the request body type in TypeScript.
Response Body
application/json
application/json
application/json
application/json
application/json
application/json
application/json
curl -X POST "https://example.com/codes/batch" \ -H "Content-Type: application/json" \ -d '{ "codes": [ "99213", "E11.9", "27447" ] }'{ "success": true, "data": { "results": { "property1": { "code": "76942", "code_system": "HCPCS", "found": true, "description": "string", "short_description": "string", "category": "string", "betos_code": "string", "poa_exempt": true, "is_active": true, "rvu": { "work_rvu": "string", "pe_rvu_nonfacility": "string", "pe_rvu_facility": "string", "mp_rvu": "string", "total_rvu_nonfacility": "string", "total_rvu_facility": "string", "non_facility_price": "string", "facility_price": "string", "conversion_factor": "string", "global_days": "string", "status_code": "string", "year": 0 }, "negotiated_rates": { "min_rate": "string", "max_rate": "string", "avg_rate": "string", "num_rates": 0, "payer": "string", "arrangement": "string", "source": "string", "payer_scope": "string", "as_of": "string", "billing_code_set": "string", "is_current": true }, "policies": [ { "policy_id": "string", "title": "string", "policy_type": "string", "disposition": "string", "source": "document", "grounding": "grounded", "jurisdiction": "string", "applicability_scope": "shared_markets", "applicability_markets": [ "string" ], "applicability_evidence": { "document_sha256": "string", "market_index_listings": [ { "market": "string", "index_url": "string" } ], "document_statements": [ { "kind": "non_medicare_disclaimer", "quote": "string", "page": 1 } ] }, "applicability_note": "string", "effective_date": "string", "source_url": "string", "public_url": "https://backworkhealth.com/policy/L33831", "source_check": { "source_url": "https://www.cms.gov/medicare-coverage-database/view/lcd.aspx?lcdid=33831", "last_fetched_at": "2019-08-24T14:15:22Z", "content_sha256": "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08", "source_accuracy": [ { "field": "overall", "sampled_at": "2019-08-24T14:15:22Z", "sample_size": 120, "accuracy": 0.9667, "ci_low": 0.917, "ci_high": 0.987, "method": "manual_review_v1" } ] } } ], "suggestions": [ { "code": "string", "code_system": "string", "description": "string", "score": 0, "match_type": "code" } ], "ndc_crosswalk": { "ndc": "string", "hcpcs_code": "string", "hcpcs_description": "string", "ndc_label": "string", "route": "string", "billing_units": "string", "conversion_factor": "string" } }, "property2": { "code": "76942", "code_system": "HCPCS", "found": true, "description": "string", "short_description": "string", "category": "string", "betos_code": "string", "poa_exempt": true, "is_active": true, "rvu": { "work_rvu": "string", "pe_rvu_nonfacility": "string", "pe_rvu_facility": "string", "mp_rvu": "string", "total_rvu_nonfacility": "string", "total_rvu_facility": "string", "non_facility_price": "string", "facility_price": "string", "conversion_factor": "string", "global_days": "string", "status_code": "string", "year": 0 }, "negotiated_rates": { "min_rate": "string", "max_rate": "string", "avg_rate": "string", "num_rates": 0, "payer": "string", "arrangement": "string", "source": "string", "payer_scope": "string", "as_of": "string", "billing_code_set": "string", "is_current": true }, "policies": [ { "policy_id": "string", "title": "string", "policy_type": "string", "disposition": "string", "source": "document", "grounding": "grounded", "jurisdiction": "string", "applicability_scope": "shared_markets", "applicability_markets": [ "string" ], "applicability_evidence": { "document_sha256": "string", "market_index_listings": [ { "market": "string", "index_url": "string" } ], "document_statements": [ { "kind": "non_medicare_disclaimer", "quote": "string", "page": 1 } ] }, "applicability_note": "string", "effective_date": "string", "source_url": "string", "public_url": "https://backworkhealth.com/policy/L33831", "source_check": { "source_url": "https://www.cms.gov/medicare-coverage-database/view/lcd.aspx?lcdid=33831", "last_fetched_at": "2019-08-24T14:15:22Z", "content_sha256": "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08", "source_accuracy": [ { "field": "overall", "sampled_at": "2019-08-24T14:15:22Z", "sample_size": 120, "accuracy": 0.9667, "ci_low": 0.917, "ci_high": 0.987, "method": "manual_review_v1" } ] } } ], "suggestions": [ { "code": "string", "code_system": "string", "description": "string", "score": 0, "match_type": "code" } ], "ndc_crosswalk": { "ndc": "string", "hcpcs_code": "string", "hcpcs_description": "string", "ndc_label": "string", "route": "string", "billing_units": "string", "conversion_factor": "string" } } } }, "meta": { "request_id": "string", "timestamp": "2019-08-24T14:15:22Z", "total_codes": 0, "unique_codes": 0, "includes": [ "string" ], "attributions": { "disclaimer": "string", "cpt": "string", "loinc": "string", "cms": "string", "payer_data": "string", "negotiated_rates": "string" } }}Last updated on