> ## Documentation Index
> Fetch the complete documentation index at: https://docs.blockscout.com/llms.txt
> Use this file to discover all available pages before exploring further.

# List FHE operations for a specific transaction

> Retrieves Fully Homomorphic Encryption (FHE) operations parsed from transaction logs. Includes operation details, HCU (Homomorphic Compute Unit) costs, operation types, and related metadata.



## OpenAPI

````yaml /openapi-specs/pro-api-v11.yaml get /v2/transactions/{transaction_hash_param}/fhe-operations
openapi: 3.0.0
info:
  contact:
    email: info@blockscout.com
  title: Blockscout
  version: 11.0.3
servers:
  - url: http://localhost/api
    variables: {}
security: []
tags:
  - name: blocks
  - name: transactions
  - name: addresses
  - name: internal-transactions
  - name: tokens
  - name: token-transfers
  - name: smart-contracts
  - name: config
  - name: main-page
  - name: search
  - name: stats
  - name: csv-export
  - name: account-abstraction
  - name: withdrawals
  - name: advanced-filters
  - name: arbitrum
  - name: legacy
  - name: optimism
  - name: mud
  - name: celo
  - name: scroll
  - name: zilliqa
paths:
  /v2/transactions/{transaction_hash_param}/fhe-operations:
    get:
      tags:
        - transactions
      summary: List FHE operations for a specific transaction
      description: >-
        Retrieves Fully Homomorphic Encryption (FHE) operations parsed from
        transaction logs. Includes operation details, HCU (Homomorphic Compute
        Unit) costs, operation types, and related metadata.
      operationId: BlockScoutWeb.API.V2.TransactionController.fhe_operations
      parameters:
        - description: Transaction hash in the path
          in: path
          name: transaction_hash_param
          required: true
          schema:
            $ref: '#/components/schemas/FullHash'
        - description: API key for rate limiting or for sensitive endpoints
          in: query
          name: apikey
          required: false
          schema:
            type: string
            x-struct: null
            x-validate: null
        - description: Secret key for getting access to restricted resources
          in: query
          name: key
          required: false
          schema:
            type: string
            x-struct: null
            x-validate: null
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/FheOperationsResponse'
          description: >-
            FHE operations for the specified transaction with transaction-level
            metrics.
        '404':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/NotFoundResponse'
          description: Not Found
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/JsonErrorResponse'
          description: Unprocessable Entity
      callbacks: {}
components:
  schemas:
    FullHash:
      nullable: false
      pattern: ^0x([A-Fa-f0-9]{64})$
      title: FullHash
      type: string
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.General.FullHash
      x-validate: null
    FheOperationsResponse:
      additionalProperties: false
      properties:
        items:
          items:
            allOf:
              - $ref: '#/components/schemas/FheOperation'
            nullable: false
            x-struct: null
            x-validate: null
          nullable: false
          type: array
          x-struct: null
          x-validate: null
        max_depth_hcu:
          description: Maximum HCU depth across all operations in the transaction
          example: 3
          minimum: 0
          nullable: false
          type: integer
          x-struct: null
          x-validate: null
        operation_count:
          description: Total number of FHE operations in the transaction
          example: 5
          minimum: 0
          nullable: false
          type: integer
          x-struct: null
          x-validate: null
        total_hcu:
          description: >-
            Total HCU (Homomorphic Compute Units) cost for all operations in the
            transaction
          example: 500
          minimum: 0
          nullable: false
          type: integer
          x-struct: null
          x-validate: null
      required:
        - items
        - total_hcu
        - max_depth_hcu
        - operation_count
      title: FheOperationsResponse
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.FheOperationsResponse
      x-validate: null
    NotFoundResponse:
      description: Response returned when the requested resource is not found
      properties:
        message:
          description: Error message indicating the requested resource was not found
          example: Resource not found
          type: string
          x-struct: null
          x-validate: null
      title: NotFoundResponse
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.ErrorResponses.NotFoundResponse
      x-validate: null
    JsonErrorResponse:
      properties:
        errors:
          items:
            properties:
              detail:
                example: null value where string expected
                type: string
                x-struct: null
                x-validate: null
              source:
                properties:
                  pointer:
                    example: /data/attributes/petName
                    type: string
                    x-struct: null
                    x-validate: null
                required:
                  - pointer
                type: object
                x-struct: null
                x-validate: null
              title:
                example: Invalid value
                type: string
                x-struct: null
                x-validate: null
            required:
              - title
              - source
              - detail
            type: object
            x-struct: null
            x-validate: null
          type: array
          x-struct: null
          x-validate: null
      required:
        - errors
      title: JsonErrorResponse
      type: object
      x-struct: Elixir.OpenApiSpex.JsonErrorResponse
      x-validate: null
    FheOperation:
      additionalProperties: false
      properties:
        block_number:
          example: 12345678
          nullable: false
          type: integer
          x-struct: null
          x-validate: null
        caller:
          allOf:
            - $ref: '#/components/schemas/Address'
          nullable: true
          x-struct: null
          x-validate: null
        fhe_type:
          enum:
            - Bool
            - Uint8
            - Uint16
            - Uint32
            - Uint64
            - Uint128
            - Uint160
            - Uint256
            - Bytes64
            - Bytes128
            - Bytes256
          example: Uint8
          nullable: false
          type: string
          x-struct: null
          x-validate: null
        hcu_cost:
          example: 100
          minimum: 0
          nullable: false
          type: integer
          x-struct: null
          x-validate: null
        hcu_depth:
          example: 1
          minimum: 0
          nullable: false
          type: integer
          x-struct: null
          x-validate: null
        inputs:
          additionalProperties: false
          properties:
            control:
              nullable: true
              type: string
              x-struct: null
              x-validate: null
            ct:
              nullable: true
              type: string
              x-struct: null
              x-validate: null
            if_false:
              nullable: true
              type: string
              x-struct: null
              x-validate: null
            if_true:
              nullable: true
              type: string
              x-struct: null
              x-validate: null
            lhs:
              nullable: true
              type: string
              x-struct: null
              x-validate: null
            plaintext:
              nullable: true
              type: number
              x-struct: null
              x-validate: null
            rhs:
              nullable: true
              type: string
              x-struct: null
              x-validate: null
          type: object
          x-struct: null
          x-validate: null
        is_scalar:
          example: false
          nullable: false
          type: boolean
          x-struct: null
          x-validate: null
        log_index:
          nullable: false
          type: integer
          x-struct: null
          x-validate: null
        operation:
          example: FheAdd
          nullable: false
          type: string
          x-struct: null
          x-validate: null
        result:
          $ref: '#/components/schemas/HexString'
        type:
          enum:
            - arithmetic
            - bitwise
            - comparison
            - unary
            - control
            - encryption
            - random
          example: arithmetic
          nullable: false
          type: string
          x-struct: null
          x-validate: null
      required:
        - log_index
        - operation
        - type
        - fhe_type
        - is_scalar
        - hcu_cost
        - hcu_depth
        - inputs
        - result
        - block_number
      title: FheOperation
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.FheOperation
      x-validate: null
    Address:
      additionalProperties: false
      description: Address
      properties:
        ens_domain_name:
          description: ENS domain name associated with the address
          nullable: true
          type: string
          x-struct: null
          x-validate: null
        hash:
          $ref: '#/components/schemas/AddressHash'
        implementations:
          description: Implementations linked with the contract
          items:
            $ref: '#/components/schemas/Implementation'
          type: array
          x-struct: null
          x-validate: null
        is_contract:
          description: Has address contract code?
          nullable: true
          type: boolean
          x-struct: null
          x-validate: null
        is_scam:
          description: Has address scam badge?
          nullable: false
          type: boolean
          x-struct: null
          x-validate: null
        is_verified:
          description: Has address associated source code?
          nullable: true
          type: boolean
          x-struct: null
          x-validate: null
        metadata:
          allOf:
            - $ref: '#/components/schemas/Metadata'
          nullable: true
          x-struct: null
          x-validate: null
        name:
          description: Name associated with the address
          nullable: true
          type: string
          x-struct: null
          x-validate: null
        private_tags:
          description: Private tags associated with the address
          items:
            $ref: '#/components/schemas/Tag'
          type: array
          x-struct: null
          x-validate: null
        proxy_type:
          $ref: '#/components/schemas/ProxyType'
        public_tags:
          description: Public tags associated with the address
          items:
            $ref: '#/components/schemas/Tag'
          type: array
          x-struct: null
          x-validate: null
        reputation:
          description: Reputation of the address
          enum:
            - ok
            - scam
          nullable: false
          type: string
          x-struct: null
          x-validate: null
        watchlist_names:
          description: Watchlist name associated with the address
          items:
            $ref: '#/components/schemas/WatchlistName'
          type: array
          x-struct: null
          x-validate: null
      required:
        - hash
        - is_contract
        - name
        - is_scam
        - reputation
        - proxy_type
        - implementations
        - is_verified
        - ens_domain_name
        - metadata
      title: Address
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.Address
      x-validate: null
    HexString:
      nullable: false
      pattern: ^0x([A-Fa-f0-9]*)$
      title: HexString
      type: string
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.General.HexString
      x-validate: null
    AddressHash:
      nullable: false
      pattern: ^0x([A-Fa-f0-9]{40})$
      title: AddressHash
      type: string
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.General.AddressHash
      x-validate: null
    Implementation:
      additionalProperties: false
      description: Proxy smart contract implementation
      properties:
        address_hash:
          $ref: '#/components/schemas/AddressHash'
        name:
          nullable: true
          type: string
          x-struct: null
          x-validate: null
      required:
        - address_hash
        - name
      title: Implementation
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.General.Implementation
      x-validate: null
    Metadata:
      additionalProperties: false
      description: Metadata struct
      properties:
        tags:
          description: Metadata tags linked with the address
          items:
            $ref: '#/components/schemas/MetadataTag'
          type: array
          x-struct: null
          x-validate: null
      required:
        - tags
      title: Metadata
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.Proxy.Metadata
      x-validate: null
    Tag:
      additionalProperties: false
      description: Address tag struct
      properties:
        address_hash:
          $ref: '#/components/schemas/AddressHash'
        display_name:
          nullable: false
          type: string
          x-struct: null
          x-validate: null
        label:
          nullable: false
          type: string
          x-struct: null
          x-validate: null
      required:
        - address_hash
        - display_name
        - label
      title: Tag
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.General.Tag
      x-validate: null
    ProxyType:
      enum:
        - eip1167
        - eip1967
        - eip1822
        - eip1967_oz
        - eip1967_beacon
        - master_copy
        - basic_implementation
        - basic_get_implementation
        - comptroller
        - eip2535
        - clone_with_immutable_arguments
        - eip7702
        - resolved_delegate_proxy
        - erc7760
      nullable: true
      title: ProxyType
      type: string
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.General.ProxyType
      x-validate: null
    WatchlistName:
      additionalProperties: false
      description: Watchlist name struct
      properties:
        display_name:
          nullable: false
          type: string
          x-struct: null
          x-validate: null
        label:
          nullable: false
          type: string
          x-struct: null
          x-validate: null
      required:
        - display_name
        - label
      title: WatchlistName
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.General.WatchlistName
      x-validate: null
    MetadataTag:
      additionalProperties: false
      description: Metadata tag struct
      properties:
        meta:
          nullable: false
          type: object
          x-struct: null
          x-validate: null
        name:
          nullable: false
          type: string
          x-struct: null
          x-validate: null
        ordinal:
          nullable: false
          type: integer
          x-struct: null
          x-validate: null
        slug:
          nullable: false
          type: string
          x-struct: null
          x-validate: null
        tagType:
          nullable: false
          type: string
          x-struct: null
          x-validate: null
      required:
        - slug
        - name
        - tagType
        - ordinal
        - meta
      title: MetadataTag
      type: object
      x-struct: Elixir.BlockScoutWeb.Schemas.API.V2.Proxy.MetadataTag
      x-validate: null

````