ots namespace
Reth implements part of the Otterscan API.
Enable the namespace with --http.api eth,ots (or include ots in your existing
HTTP or WebSocket API selection).
ots_getApiLevel returns 8, but this does not guarantee complete support
for API level 8 or for every feature of the Otterscan frontend.
Supported methods
| Method | Behavior |
|---|---|
ots_getApiLevel | Returns 8. |
ots_getHeaderByNumber | Returns a header, or null for an unknown block. Also exposed as erigon_getHeaderByNumber for frontend compatibility. |
ots_hasCode | Checks code at the requested block; defaults to latest state. |
ots_getTransactionError | Returns raw revert bytes. A known transaction with no revert data (including success and exceptional halt) returns "0x". An unknown transaction returns null. Check the receipt status to distinguish success from failure. |
ots_traceTransaction | Returns call, creation and self-destruct entries, or null for an unknown transaction. Includes precompile calls. |
ots_getInternalOperations | Returns internal nonzero-value calls, creations (including zero endowment), and self-destructs. Excludes the transaction's top-level call or creation. An unknown transaction returns an empty array. |
ots_getBlockDetails | Returns block metadata, execution fees, and issuance using the chain's Ethereum hardfork schedule. |
ots_getBlockDetailsByHash | The same block details, selected by hash. |
ots_getBlockTransactions | Returns paginated transactions and matching receipts. |
ots_getTransactionBySenderAndNonce | Searches canonical transaction history for a sender and nonce; excludes pending transactions. Returns null if not found. |
ots_getContractCreator | Searches historical code and traces for a creation transaction, subject to the limitations below. Returns null if no creator is found. |
Block details and block transaction methods return an RPC error when the block or required receipts are unavailable. They do not return an empty block.
Block issuance includes the proof-of-work miner reward, the miner's ommer
inclusion rewards, and the ommers' rewards. It is zero for genesis and from the
Paris (Merge) activation configured in the chain specification. It does not
include consensus-layer issuance or withdrawals. totalFees sums execution gas
used times effective gas price, including the base fee; it excludes blob fees
and is not the miner's fee income.
Block transaction pages are zero-indexed from the end of the block, with
transactions and receipts in ascending block order within each page. For 25
transactions and a page size of 10, pages contain indices 15–24, 5–14, and 0–4.
Out-of-range pages and a page size of zero return empty lists. The original
block transaction count is retained. Transaction input is capped to the first
four bytes; receipt logs and log blooms are null.
Tracing reports attempted operations, including operations reverted by an
enclosing call. These entries are not a list of committed balance changes.
SELFDESTRUCT is represented separately from the call that executes it; after
Cancun it does not necessarily delete the contract. STATICCALL and
DELEGATECALL trace entries have a null value.
Unimplemented address history search
ots_searchTransactionsBefore and ots_searchTransactionsAfter are registered
but unimplemented. Both return this JSON-RPC error:
{"code": -32603, "message": "unimplemented"}Enabling ots or running an archive node does not enable these endpoints.
Otterscan address transaction history therefore remains unavailable through
these methods. Implementing them requires efficient address/call history
indexing or another bounded search strategy; replaying arbitrary chain history
per request is not a practical substitute.
Earlier work is recorded in closed issue #13499. The closed prototype PR #13621 contains earlier implementation and indexing discussion. Cross-client response and specification alignment is discussed in Otterscan #1081.
History and state requirements
Historical code queries need state for the selected block. Tracing methods need the transaction, its block, and state sufficient to replay it, including preceding transactions when necessary. Pruned state, receipts, bodies, or transaction lookup data can prevent these methods from answering older queries. Archive state alone does not restore other pruned history. Replays and historical searches can be expensive.
Contract creator lookup currently binary-searches code presence, assuming one
transition from absent to present. Destruction and redeployment violate that
assumption, so the result is not a reliable first-deployment record for such
contracts. Contracts without code at latest state return null; genesis
allocations and code set through EIP-7702 delegation have no corresponding
CREATE/CREATE2 transaction and may also return null. A complete solution
needs creation history rather than code-presence binary search; address history
work above is a related indexing follow-up.