> ## Documentation Index > Fetch the complete documentation index at: https://docs.rcintell.com/llms.txt > Use this file to discover all available pages before exploring further. # Policies that reference an ICD-10-CM diagnosis > Which policies list this diagnosis as covered or non-covered, and for which CPTs. Matches the code exactly, by ancestor (a policy listing ``E11`` covers ``E11.65``) and, for categories, by descendant. Each row names the CPT/HCPCS the diagnosis pairs with and any asterisk note (e.g. not as primary). With ``cpt``, ``processing`` gives the LCD/NCD verdict for that pair. ## OpenAPI ````yaml /docs/openapi.client.json get /v1/policies/by-dx openapi: 3.1.0 info: description: >- Client API for RCIntel. Authenticate with X-API-Key. See Guides → Which API to use. summary: Multi-tenant knowledge API for healthcare revenue cycle management. title: Healthcare Knowledge Layer version: 0.1.0 servers: [] security: [] tags: - description: >- Cited payer policy lookup — GET /v1/policies and GET /v1/policies/changes. Medicare FFS returns NCDs/LCDs/MACs; commercial payers return that payer's documents only. Query payer, code, state, plan_type. name: policies - description: >- Payer-policy PDF parse and retrieve for Workspace / Payer Knowledge. Service-authenticated (X-Admin-Secret); chunks stored in Postgres. name: policy - description: >- Manufacturer 340B contract-pharmacy policy, fail-closed access, and the change feed. Different API from GET /v1/policies. name: 340B Policy - description: CRD-style prior authorization check, documentation, and vendors. name: prior-auth - description: Public payer directory (no API key on list/detail). name: payers-public - description: >- Payer network directory — search payers, check prior auth requirements, view filing rules, denial patterns, and appeal levels. name: payers - description: >- Resolve healthcare billing knowledge across the L1-L6 layer stack. Includes payment calculation, billing guidance, and per-layer queries. name: knowledge - description: >- CMS Fee Schedule lookups — OPPS (Addendum B / APC), DMEPOS (state-level pricing), and Clinical Lab Fee Schedule (CLFS). name: fee-schedules - description: >- NCCI (National Correct Coding Initiative) — dedicated MUE limits, PTP bundling edits, add-on code edits, and code pair validation. Medicare edits under /ncci/*, the separate CMS Medicaid edit set under /ncci/medicaid/*. name: ncci - description: >- Service code intelligence — CPT/HCPCS lookup, RVU data, NCCI edits, payment calculation, implant/GUDID search, and service group classification. name: codes - description: >- Submit asynchronous AI agent jobs for code research, medical necessity, and denial resolution. Poll for results and retrieve reasoning traces. name: agents - description: >- Register and manage healthcare facilities by CCN (Medicare Provider Number). Each facility is the root entity for knowledge resolution. name: facilities - description: >- NPI Registry — live search against CMS NPPES API for provider and organization National Provider Identifiers. name: npi - description: >- OpenFDA drug product lookup by NDC. Includes product-level fields with normalized ingredient and package detail. name: drugs - name: encounter - name: mcp - description: Health checks, service metadata, and Prometheus metrics. name: system paths: /v1/policies/by-dx: get: tags: - policies summary: Policies that reference an ICD-10-CM diagnosis description: >- Which policies list this diagnosis as covered or non-covered, and for which CPTs. Matches the code exactly, by ancestor (a policy listing ``E11`` covers ``E11.65``) and, for categories, by descendant. Each row names the CPT/HCPCS the diagnosis pairs with and any asterisk note (e.g. not as primary). With ``cpt``, ``processing`` gives the LCD/NCD verdict for that pair. operationId: list_policies_by_dx_v1_policies_by_dx_get parameters: - description: ICD-10-CM code, dotted or not (E11.65 or E1165) in: query name: dx required: true schema: description: ICD-10-CM code, dotted or not (E11.65 or E1165) title: Dx type: string - description: Payer slug; default Medicare FFS in: query name: payer required: false schema: anyOf: - type: string - type: 'null' description: Payer slug; default Medicare FFS title: Payer - description: >- Optional CPT/HCPCS: limits to policies pairing it with dx and adds a coverage verdict in: query name: cpt required: false schema: anyOf: - type: string - type: 'null' description: >- Optional CPT/HCPCS: limits to policies pairing it with dx and adds a coverage verdict title: Cpt - description: US state → Medicare MAC for LCD localization in: query name: state required: false schema: anyOf: - type: string - type: 'null' description: US state → Medicare MAC for LCD localization title: State - description: Optional facility type filter (fqhc, rhc, ...) in: query name: facility_type required: false schema: anyOf: - type: string - type: 'null' description: Optional facility type filter (fqhc, rhc, ...) title: Facility Type - description: For a category (E11), also match policies listing its child codes in: query name: include_descendants required: false schema: default: true description: For a category (E11), also match policies listing its child codes title: Include Descendants type: boolean - description: Maximum number of records to return. in: query name: limit required: false schema: default: 100 maximum: 500 minimum: 1 title: Limit type: integer responses: '200': content: application/json: schema: $ref: '#/components/schemas/DxPolicyLookupResponse' description: Successful Response '422': content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' description: Validation Error security: - APIKeyHeader: [] components: schemas: DxPolicyLookupResponse: properties: count: title: Count type: integer cpt: anyOf: - type: string - type: 'null' title: Cpt dx: title: Dx type: string dx_description: anyOf: - type: string - type: 'null' description: Null until the ICD-10-CM table is loaded title: Dx Description dx_normalized: title: Dx Normalized type: string facility_type: anyOf: - type: string - type: 'null' title: Facility Type mac: anyOf: - additionalProperties: true type: object - type: 'null' title: Mac payer: title: Payer type: string policies: items: $ref: '#/components/schemas/DxPolicyRow' title: Policies type: array processing: anyOf: - $ref: '#/components/schemas/DxProcessing' - type: 'null' state: anyOf: - type: string - type: 'null' title: State warnings: items: type: string title: Warnings type: array required: - dx - dx_normalized - payer - count title: DxPolicyLookupResponse type: object HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' title: Detail type: array title: HTTPValidationError type: object DxPolicyRow: description: One policy that references the requested diagnosis. properties: contractors: anyOf: - type: string - type: 'null' title: Contractors document_kind: description: lcd_article (more kinds as stores are added) title: Document Kind type: string dx_group: anyOf: - type: integer - type: 'null' title: Dx Group facility_applicability: anyOf: - type: string - type: 'null' title: Facility Applicability facility_tag_source: anyOf: - type: string - type: 'null' title: Facility Tag Source facility_types: items: type: string title: Facility Types type: array group_note: anyOf: - type: string - type: 'null' description: Asterisk note for this DX, e.g. not as primary title: Group Note match: description: >- exact | ancestor (a category listed) | descendant (a child code listed) title: Match type: string matched_entry: description: The ICD-10 entry as the policy lists it title: Matched Entry type: string paired_cpts: description: CPT/HCPCS the DX pairs with in this policy items: type: string title: Paired Cpts type: array pairing_grain: default: code_group title: Pairing Grain type: string payer_slug: title: Payer Slug type: string policy_id: title: Policy Id type: string relationship: description: covered | non_covered title: Relationship type: string source: title: Source type: string title: title: Title type: string url: anyOf: - type: string - type: 'null' title: Url required: - payer_slug - document_kind - policy_id - title - relationship - match - matched_entry - source title: DxPolicyRow type: object DxProcessing: description: Medical-necessity verdict for the requested CPT + DX pair. properties: coverage_status: anyOf: - type: string - type: 'null' title: Coverage Status cpt: title: Cpt type: string lcd_id: anyOf: - type: string - type: 'null' title: Lcd Id matched_dx: items: type: string title: Matched Dx type: array ncd_id: anyOf: - type: string - type: 'null' title: Ncd Id policy_title: anyOf: - type: string - type: 'null' title: Policy Title primary_covered: default: false title: Primary Covered type: boolean source: anyOf: - type: string - type: 'null' title: Source source_url: anyOf: - type: string - type: 'null' title: Source Url required: - cpt title: DxProcessing type: object ValidationError: properties: ctx: title: Context type: object input: title: Input loc: items: anyOf: - type: string - type: integer title: Location type: array msg: title: Message type: string type: title: Error Type type: string required: - loc - msg - type title: ValidationError type: object securitySchemes: APIKeyHeader: in: header name: X-API-Key type: apiKey ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.