Time travel

Time travel answers node (algod) API questions as of a past round: an account’s balance and holdings, an app’s global state or a box at any round since genesis, the rounds at which they changed, and a transaction group simulated against past state. A stock node only knows the latest state; Nodely routes these requests to time-travel nodes that keep the history of every ledger object.

Who gets it

Plan	Time travel
Free	Testnet time travel
Boost	Basic time travel (mainnet and testnet)
Unlimited	Full time travel (mainnet and testnet)
Enterprise	Full time travel (mainnet and testnet)

Testnet history is open to everyone, on the free hosts as well, under the usual free-tier limits.
Mainnet history needs a paid plan: send a token, or call from a whitelisted site (or IP, on Unlimited and Enterprise). Boost uses the public nodely.dev hosts, Unlimited and Enterprise the commercial hosts. Public goods projects on Unlimited get it too. Without a plan, mainnet history requests are rejected with an error; an organization admin can upgrade on the Billing page.
History requests count toward your daily quota and rate limits like any other request.

What counts as a history request

The edge sends these requests to the time-travel nodes and everything else to the regular nodes:

Request	Answers
`GET /v2/accounts/{address}?round=R`, and its `/assets`, `/applications`, `/assets/{id}`, `/applications/{id}`	The account, its holdings and local states at the end of round R
`GET /v2/assets/{id}?round=R`, `GET /v2/applications/{id}?round=R`	Asset parameters, app parameters and global state at R
`GET /v2/applications/{id}/box?name=…&round=R`, `/boxes?round=R`	A box value, or the app’s boxes, at R
`GET /v2/ledger/supply?round=R`	Totals at R
`GET …/versions`, for example `/v2/accounts/{address}/versions`	The rounds at which an object changed, paginated, with the new values on `include=values`
`POST /v2/transactions/simulate` with `"round": R`	The group evaluated as if it were in block R+1

Simulate requests that use the fork’s other extensions (rounds, parallel-groups, protocol) count as history requests too. The full list of endpoints, parameters and known limitations is in the dt-algorand time travel docs, and the versions API in VERSIONS.md.

Examples

# Mainnet, paid plan: an account as it was at the end of round 50,000,000
curl -H "X-API-Key: $NODELY_TOKEN" \
  "https://mainnet-api.4160.nodely.io/v2/accounts/$ADDRESS?round=50000000"

# The rounds at which the account changed between two rounds, newest first
curl -H "X-API-Key: $NODELY_TOKEN" \
  "https://mainnet-api.4160.nodely.io/v2/accounts/$ADDRESS/versions?min-round=49000000&max-round=50000000&order=desc&limit=10"

# Testnet, free host, no key: an app's global state at a past round
curl "https://testnet-api.4160.nodely.dev/v2/applications/$APP_ID?round=40000000"

To simulate at a past round, add round to the usual simulate request body:

{
  "txn-groups": [{ "txns": ["…signed or unsigned transactions…"] }],
  "allow-empty-signatures": true,
  "round": 50000000
}

Errors

Response	Meaning
An error on a mainnet history request without a plan	Mainnet history needs a paid plan: send your token, or call from a whitelisted site or IP.
`503 {"message":"historical state (time travel) service unavailable"}`	The time-travel nodes cannot be reached. The edge does not fall back to a regular node, because it would answer with the latest state instead. Retry with backoff.
`404` on `/v2/ledger/supply?round=`	The online stake for that round was not recorded.

Indexer APIs are not affected: they keep their own round and min-round / max-round parameters.