On-chain REST

/v1/onchain/ answers questions about EVM addresses and ERC-20 tokens: what a wallet holds, who it trades with, where its money went, who is accumulating a token, and which labelled institution sits behind an address. 15 endpoints, all on https://data.vike.io, all behind the API key and the shared hourly budget.

The chain is a filter, not a namespace — ?chain=ethereum|bsc|base on most routes, because the data behind this namespace is multi-chain by design.

Every call carries the credential in a header — X-API-Key: vk_... or Authorization: Bearer vk_oat_..., either alone is enough (Authentication) — and spends one unit of the shared hourly counter (Rate limits):

# the 20 counterparties this wallet moved the most USD with over the past 7 days
curl -H "X-API-Key: $VIKE_API_KEY" \
  "https://data.vike.io/v1/onchain/wallets/0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045/counterparties?window=7d&limit=20"

Each endpoint has its own page, carrying its full request line in a fence at the top; the page titles are written as the path, without the method.

Start here

What it looks like in use

# find: the wallets with the biggest net inflow over 7 days
curl -s "https://data.vike.io/v1/onchain/wallets/discover?window=7d&sort=net_flow&order=desc&size=5" \
  -H "X-API-Key: $VIKE_API_KEY"

# size one up: WALLET is an address from that board; five windows of activity in one call
curl -s "https://data.vike.io/v1/onchain/wallets/$WALLET" \
  -H "X-API-Key: $VIKE_API_KEY"

# who it deals with: its ten biggest counterparties over 30 days
curl -s "https://data.vike.io/v1/onchain/wallets/$WALLET/counterparties?window=30d&limit=10" \
  -H "X-API-Key: $VIKE_API_KEY"

# where the money went from there: two hops, five counterparties per hop
curl -s "https://data.vike.io/v1/onchain/wallets/$WALLET/trace?depth=2&width=5&window=30d" \
  -H "X-API-Key: $VIKE_API_KEY"

# who those counterparties are: CPS is their addresses joined with commas
curl -s -X POST "https://data.vike.io/v1/onchain/labels/batch?addresses=$CPS" \
  -H "X-API-Key: $VIKE_API_KEY"

Conventions on this namespace

Omitting a parameter is not the same as passing zero

A numeric parameter sent as 0 — or as an empty string — is treated exactly like one you did not send at all: the endpoint falls back to its own default, and that default is not always zero.

Two ceilings, and the lower one is silent

The limit a route accepts and the limit it applies are two different numbers. The request validator enforces the higher one; the query underneath then quietly caps at the lower one. Nothing rejects an over-cap value and nothing reports the cap — a request for 1,000 rows returns 50 and looks exactly like a wallet with only 50 counterparties.

Credits are counted differently from MCP

Every on-chain REST call logs one credit, whatever it cost to serve — no route on this namespace charges more. Over MCP the same work is priced by tool instead, from 0 (token_search) to 4 (wallet_trace, the heaviest graph traversal). The hourly request budget is separate again and charges one unit per request on every surface, this namespace included.

Errors

Status codes and the error envelope are namespace-wide and documented under Errors. The mapping: a rejected input becomes 400 carrying the reason, and any other failure becomes 503.

A rejected batch on POST /labels/batch — more than 100 addresses, or none — is a 400 like any other rejected input. A malformed address on /balances and /ens is a 400 too, with a message reading Bad EVM address: …; the check there is strict: a 0x prefix and exactly 42 characters.

An unrecognised chain name is a 400 (chain 'x' not supported (use ethereum, bsc, or base)) on /wallets/{address}/counterparties, /pnl, /transactions, /trace, /wallets/compare, /tokens/screener, /tokens/{token_address}/holders and /labels/batch. The one exception is /tokens/{token_address}/transfers, which maps an unknown chain to ethereum and answers 200.

Wallets

Nine endpoints. /wallets/compare and /wallets/discover are literal paths rather than addresses — they take no {address} segment.

Tokens

Labels