CLI anchor command: gas estimation exceeds Base Sepolia per-tx limit

[crtahlin]

Bug

When using the CLI's anchor command on Base Sepolia, the transaction can fail because the RPC gas estimation returns ~131,250,000 which exceeds Base Sepolia's per-transaction gas limit of 25,000,000.

This is the same root cause as datafund/swarm_provenance_SDK#45 — the underlying SDK's ChainClient doesn't pass a gas field in sendTransaction, so the RPC node's gas estimation is used, which can return unreasonably high values.

Error

ChainTransactionError: Transaction failed: [object Object]

(The [object Object] is a separate stringification bug in the SDK — see datafund/swarm_provenance_SDK#45.)

Expected behavior

The CLI should either:

1. Accept a --gas flag to let users override the gas limit
2. Set a sensible default gas limit (e.g., 500,000) for registerData calls
3. Or be fixed upstream via the SDK (ChainClient: gas estimation exceeds Base Sepolia per-tx limit (131M vs 25M) swarm_provenance_SDK#45)

Workaround

Consumers of the SDK are wrapping the EIP-1193 provider to inject a gas limit before passing it to fromEip1193Provider:

const DEFAULT_GAS_LIMIT = '0x7A120' // 500,000

function withGasLimitProvider(provider) {
  return {
    request(args) {
      if (args.method === 'eth_sendTransaction' && args.params?.[0]) {
        const tx = args.params[0];
        if (!tx.gas) tx.gas = DEFAULT_GAS_LIMIT;
      }
      return provider.request(args);
    },
  };
}

Related

• ChainClient: gas estimation exceeds Base Sepolia per-tx limit (131M vs 25M) swarm_provenance_SDK#45 — SDK root cause

[crtahlin]

Fixed in #79.

Added --gas option to all chain write commands and CHAIN_GAS_LIMIT env var. When set, the explicit value is used directly — no RPC estimation, no multiplier.

Usage:

# Per-command override
swarm-prov-upload chain anchor <hash> --gas 500000

# Persistent via env
export CHAIN_GAS_LIMIT=500000
swarm-prov-upload chain anchor <hash>

Commands with --gas: anchor, access, status, transfer, delegate, transform, protect.

If gas is set too low, the node rejects pre-broadcast with a clear ChainTransactionError — no gas wasted. Verified against Hardhat.