NoHostAvailableError in coreKit sign

Help - Core-Kit MPC Core Kit SDK
1

When asking for help in this category, please make sure to provide the following details:

  • SDK Version: 3.2.4

I am getting the following error when trying to use Web3AuthMPCCoreKit .sign():

Server 1: Error: Something went wrong for session admin-dev-sky.coll_auth@gmail.comdefault0hashhere-not-sure-if-confidential: NoHostAvailableError: No host could be resolved
Server 0: Error: Something went wrong for session admin-dev-sky.coll_auth@gmail.comdefault0hashhere-not-sure-if-confidential: NoHostAvailableError: No host could be resolved
Server 2: Error: Something went wrong for session admin-dev-sky.coll_auth@gmail.comdefault0hashhere-not-sure-if-confidential: NoHostAvailableError: No host could be resolved
[Nest] 124  - 06/05/2025, 10:35:48 AM   ERROR [ExceptionsHandler] MsgBroker: Party 6: Session admin-dev-accountemailhere@gmail.comdefault0hashhere-not-sure-if-confidential: Failed to receive message SignR1: JsValue(Error: Timeout
Error: Timeout

This is how I am instantiating corekit and logging in, which is all working:

        this.coreKitInstance = new Web3AuthMPCCoreKit({
            web3AuthClientId,
            web3AuthNetwork: WEB3AUTH_NETWORK.SAPPHIRE_DEVNET,
            storage: {
                getItem: async (key) => getItem(key),
                setItem: async (key, value) => setItem(key, value),
            },
            manualSync: true,
            tssLib,

            uxMode: 'nodejs',
        })

        await this.coreKitInstance.init()

        let token = await signToken(email)

        await this.coreKitInstance.loginWithJWT({
            verifier: verifier,
            verifierId: email,
            idToken: token,
        })

        console.log('userinfo', await this.coreKitInstance.getUserInfo())

And the call that is throwing the error:

            let _tx = VersionedTransaction.deserialize(
                new Uint8Array(Buffer.from(tx, 'base64'))
            )

            const serializedTransaction = _tx.message.serialize()
            const sig = await this.coreKitInstance.sign(
                Buffer.from(serializedTransaction)
            )
2

Thanks for providing detailed information, Arthur! Here’s a summary of your issue for the support team:

Issue Summary

  • SDK: MPC Core Kit SDK
  • SDK Version: 3.2.4
  • Platform: Node.js (using uxMode: ‘nodejs’)
  • Network: SAPPHIRE_DEVNET
  • Error:
    • NoHostAvailableError: No host could be resolved
    • Timeout errors during .sign() operation
  • Initialization & Login Code: Provided (see above)
  • Login Method: JWT (custom authentication)
    • Verifier Name: Provided in code (verifier)
    • verifierId: email
    • idToken: generated via signToken(email)
  • Failing Operation:
    • await this.coreKitInstance.sign(Buffer.from(serializedTransaction))

Next Steps & Suggestions

  1. Check Network Connectivity

    • The error NoHostAvailableError typically indicates that the Core Kit SDK cannot reach the Web3Auth TSS nodes. This can happen due to network restrictions, firewall rules, or misconfigured endpoints.
    • Make sure your server can access the endpoints required by SAPPHIRE_DEVNET.
      See Network Requirements for more details.

  2. Verify Network Selection

    • You are using WEB3AUTH_NETWORK.SAPPHIRE_DEVNET. If you intend to use the devnet, ensure it is currently operational and not undergoing maintenance.
    • Try switching to another network (like SAPPHIRE_MAINNET or SAPPHIRE_TESTNET) to see if the issue persists.

  3. Check TSS Library

    • Ensure that the tssLib you are using is compatible with the SDK version 3.2.4.

  4. Manual Sync

    • Since you are using manualSync: true, ensure you are calling any necessary sync methods if required by your flow.

  5. Session/Token Validity

    • Double-check that the JWT (idToken) is valid, not expired, and correctly signed.

Documentation & References

Additional Information Needed (if possible):

  • Are there any firewall or proxy settings on your server that could block outbound connections?
  • Are you able to reach the TSS endpoints from your server (try a simple curl/ping to the endpoints listed in the docs)?
  • If possible, please share a sample (redacted) JWT and JWKS endpoint for further investigation.

Let us know if you can check the above points or if you have any more logs or error details (such as full stack trace or network logs). This will help us narrow down the issue faster!

Note: This response was generated by an AI bot and may require further verification. The Web3Auth support team has tracked this issue and will be responding as soon as possible.

Additionally, we would recommend you to join our biweekly Office Hours to get this resolved even faster. Web3Auth Developer Office Hours