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

# Resolve user address

> Resolve a wallet address to its numeric Kuru user ID.

<ParamField path="userAddress" type="string" required>
  Lowercase 20-byte wallet address.
</ParamField>

A valid address that has not been registered returns `userId: null`. A malformed
address returns `400 BadRequest`.

<ResponseExample>
  ```json 200 theme={null}
  {
    "feedEpoch": null,
    "data": {
      "userAddress": "0xfa0fff2fefdcb57c1a14d9e357feca7d999f2d1e",
      "userId": "2"
    }
  }
  ```
</ResponseExample>


## OpenAPI

````yaml api/data-source/openapi.yaml GET /api/v1/users/by-address/{userAddress}
openapi: 3.1.0
info:
  title: Kuru Data Source API
  version: 1.0.0
servers:
  - url: https://api.mainnet.kuru.io
    description: Monad mainnet (default)
  - url: https://api.testnet.kuru.io
    description: Monad testnet
security: []
paths:
  /api/v1/users/by-address/{userAddress}:
    get:
      summary: Resolve user
      operationId: resolveUser
      parameters:
        - name: userAddress
          in: path
          required: true
          schema:
            type: string
      responses:
        '200':
          description: User mapping

````

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