What is public

Source bitcoinuniverseio/core (private)

Path verified live against https://api.bitcoinuniverse.io

Chain bitcoin

Network mainnet

Verified 2026-09-01

The public API is at https://api.bitcoinuniverse.io, port 443. It serves reads. There is no public write surface.

What is documented, and what is not

The OpenAPI 3.1 document describes thirteen GET operations, every one of which was verified against the live service on 1 September 2026 from an unauthenticated client.

Private, operator, admin, and authenticated mutation routes are deliberately absent. Their absence is not an oversight: they are not part of the public surface, and documenting something you cannot call would be worse than saying nothing. A 404 on a path that is not in the document is intentional and does not imply that an internal service exists there.

The endpoints

Endpoint	Answers
`GET /health`	Release identity, read readiness, marketplace profile, and every reason mutation traffic is closed
`GET /indexer-health`	Per-protocol index identity, tip, node tip, lag, freshness, and status, for all 29
`GET /ordinals/status`	The Ordinals index status page, as HTML
`GET /mempool/api/blocks/tip/height`	Chain tip height, as plain text
`GET /mempool/api/blocks/tip/hash`	Chain tip hash, as plain text
`GET /mempool/api/block-height/{height}`	Block hash at a height, as plain text
`GET /mempool/api/blocks`	Recent block summaries
`GET /mempool/api/mempool`	Mempool transaction count and virtual size
`GET /mempool/api/v1/fees/recommended`	Fee rates in satoshis per virtual byte
`GET /mempool/api/address/{address}`	Funded and spent totals, confirmed and mempool kept apart
`GET /mempool/api/address/{address}/utxo`	Unspent outputs
`GET /mempool/api/address/{address}/txs`	Transactions involving an address
`GET /mempool/api/tx/{txid}`	One transaction, with previous outputs

Headers every response carries

Header	What it is for
`X-Universe-Release`	The exact commit the deployment was built from. Core’s release identifier: there is no semantic version string
`X-Request-Id`	Correlation id. Quote it when reporting a problem
`Server-Timing`	Attribution to database, upstream, and application time, so a slow response can be explained

Health responses additionally carry Cache-Control: no-store. A cached readiness answer would be worse than none.

Rate limits

Chain reads carry RateLimit-Limit and RateLimit-Remaining. A 429 means wait for the indicated interval before retrying.

Per-client protections cover burst rate, sustained rate, concurrency, request size, response size, and upstream timeout.

The error envelope

Every route uses the same shape:

{
  "message": "Ordinals proxy path is not available.",
  "error": "NOT_FOUND",
  "statusCode": 404,
  "requestId": "f40208c7-2a2f-4bcb-86da-0d280f5512f4"
}

error is a stable code you can branch on. message is for a human.

The rule that matters for a caller

A read that fails answers with an explicit failure. It never answers with a zero or an empty array.

An empty array from a UTXO or transaction list means the address was read and holds nothing.
An error status means nothing is known.

There is no public-provider fallback behind these endpoints, so a failure is a real failure rather than a hint to try a different upstream. Treat the quantity as unknown, wait, and retry.

A worked example

# Which index answered for Ordinals, and how far behind was it?
curl -s https://api.bitcoinuniverse.io/indexer-health \
  | jq '.data[] | select(.protocolId=="ordinals")
        | {indexerIdentity, tip, nodeTip, lag, lastSuccess, status}'

# Is trading open at all right now?
curl -s https://api.bitcoinuniverse.io/health \
  | jq '{release, marketplaceProfile,
         read: .readTraffic.ready,
         mutate: .mutationTraffic.ready,
         cycles: .mutationTraffic.authorityCycles}'