DEVELOPERS / VERIFIED PUBLIC API

Build on the same data the observatory trusts.

Every endpoint below is served with multi-observer agreement (a quorum of separately run v30.1.3 observers on this deployment — process isolation, not independently operated infrastructure) and re-validated against an exact public schema before anything leaves this origin. Responses fail closed unless an endpoint below expressly documents bounded last-verified continuity. Quantum, supply, and release responses label retained data and expire it after one hour; no stale record is presented as current. Mutable Explorer machine endpoints, record lookups, and readiness remain strict. Coverage bounds are disclosed wherever an index is partial.

No authentication, no API keys. Please keep request rates neighborly (the origin enforces per-client limits). Amounts are canonical integer-sats strings; heights are exact; hashes are lowercase hex.

The visible Explorer home dashboard may temporarily display five explicitly labeled last-verified aggregates. That UI-only continuity route is not part of the machine API: keep clients on /api/explorer/*, which never substitutes retained records.

AI agents & MCP →Point any MCP-capable agent at the verified chain — one URL, no keys. Plus llms.txt.Keystone evaluation stack →Deposits-disabled, targeted regression-tested reference — run it on regtest, not with customer funds.Integration guide →Detect deposits, stream data — curl / JS / Python.Run a node →Per-OS install, blackcoin.conf, staking, pruning, systemd/docker, troubleshooting.Whitepaper →Protocol V4 spec: PQC, Gold Rush, migration, RPC & consensus reference.Chain params →Machine-readable ticker, decimals, HRP, phase heights, endpoints.OpenAPI →Full machine-readable API contract — import into Postman / Insomnia.API changelog →Version history + deprecation policy for the versioned contract (also /api/changelog.json).Verify it yourself →Reproduce every number on your own signed-source node.Brand & press kit →Logo assets, asset facts, palette, official links.Security & known issues →Private reporting, release boundaries, and current public P1 issues.

FOR EXCHANGES & CUSTODIANS / READ THIS FIRST

This is a read-only public telemetry and explorer API — not a custody integration API. It exposes verified chain and Protocol V4 accounting data for display and analytics. It does not create addresses, hold keys, track deposits, sign, or broadcast. To list or custody Blackcoin, run the signed-source v30.1.3 daemon (blackcoind) from the downloads rail against your own infrastructure and integrate via its JSON-RPC — that is the custody interface. Verify balances and history independently with the reproduction contract; the daemon is the source of truth, this API is a mirror of it.

Want a running reference to evaluate against? Blackcoin Keystone packages a v30.1.3 node with a deposits-disabled, targeted regression-tested integration daemon. It boots on regtest via docker compose up (tarball · sha256). It is not independently audited or production custody software; do not use it with customer funds.

Listing applications: [email protected]
Technical & custody integration: [email protected]
General exchange contact: [email protected]

Integrate Blackcoin into your platform

CORS is open on every read endpoint. Fetch directly from any origin — no key, no proxy: fetch("https://projectblackcoin.org/api/v3/quantum").then(r => r.json())
Stream live state. new EventSource("https://projectblackcoin.org/api/v3/quantum/stream") pushes each verified snapshot the moment the quorum accepts it — the same feed that drives this site's block river and observatory.
Trust, then verify. Every response is already re-validated against the public schema before it leaves this origin, and the schema contracts ship in the site source — mirror the validation in your own client if your risk model wants a second check.
Run your own. The daemon itself carries the full explorer surface (txindex, shadowindex, getgoldrushblock, getshadowaddress and friends are enabled in the production build) — point the open-source release from the downloads rail at your infrastructure and you can serve this entire contract yourself.
Drop in the live badge. <script src="https://projectblackcoin.org/embed.js" async></script> renders a self-updating height + materialized-credits badge anywhere (add data-target="#css-selector" to control placement).
Machine-readable contract. The full surface is described in openapi.json; live health for every endpoint is at /status, and the reproduction contract lives at /verify.
Attribution welcome, not required. If you display this data, linking the exact record on this explorer (every response includes heights and hashes) lets your users verify it independently.

GET/api/v3/quantum

Current quorum-verified Gold Rush snapshot: anchor, shadow pools, next-block projections, source identity.

Quality ladder live / delayed / last_verified by snapshot age; strong ETag keyed on a content hash of public fields; 503 with {schema_version:3,status:"unavailable"} when no snapshot inside the one-hour retention window passes validation.

SSE/api/v3/quantum/stream

Bounded text/event-stream pushing each accepted snapshot as event: snapshot.

Event id is <height>:<snapshot_id>:<quality>; retry hint 5000 ms.

GET/api/v3/lifecycle

Quorum-attested schema-12 replay marker (with commitment hash), protocol phase, and the published consensus schedule.

GET/api/quantum

Legacy schema-2 snapshot envelope, preserved unchanged for existing consumers.

GET/api/releases

Validated release catalog from the signed GitHub record: platform-classified binaries and the verification rail (checksums, SBOM, provenance, evidence).

A validated catalog may remain available for at most one hour during a GitHub interruption. Retained responses are explicitly last_verified and carry Warning: 110 plus X-Data-Quality/Verified-At/Expires-At/Age-Seconds. Download redirects are live-only and resolve the pinned GitHub asset ID to a fresh GitHub-signed target; retained or unverified asset identities return 503.

GET/api/supply

Base-chain supply sample (JSON: sats and decimal BLK). Plain-text aggregator endpoints: /api/supply/circulating and /api/supply/total.

Inner sample_* fields preserve the Explorer producer's collection and restart provenance. The outer quality/verified_at/expires_at/age_seconds fields describe this site's delivery and retention state. Samples older than 10 minutes, Explorer-retained samples, or a site disk fallback are labeled last_verified, never live, and expire one hour after sampled_at. JSON and plain-text responses carry the same X-Data-* quality headers.

GET/api/ready

Dependency readiness with separate live, operational, ready, restart-recommended, and catch-up state for each component, including an explicit fully reconciled supply read.

HTTP 200 requires observer quorum/agreement, a fresh canonical tip, synchronized required indexes, canonical address anchoring, complete base coverage, gap-free payload-complete shadow coverage, and a non-null fully validated supply sample. Operational catch-up remains an explicit 503 not_ready state and is not a restart instruction.

SSE/api/explorer/stream

Best-effort canonical-tip notifications (forward block, rollback, or same-height reorg). Legacy event:block frames retain the raw block payload and integer-height ID; additive event:block-v3 frames carry the public schema-3 envelope and height:hash ID. This is not a lossless event log or reorg replay service: refetch and reconcile by height + hash after every connect/reconnect or detected gap.

GET/explorer/address/{address}/feed.xml

Atom feed of an address's shadow payouts — watch any wallet from any RSS reader, no account needed.

GET/api/explorer/network

Live network telemetry: hashrate, difficulty, connections, mempool, chain size, and the observed peer-version mix (aggregate only — no peer addresses).

GET/api/explorer/status

Chain status, observer agreement, tip freshness, per-index state, and canonical base/shadow coverage integrity.

GET/api/explorer/recent-blocks?limit=1..50&before=<height>

Newest blocks with base and shadow summaries; `before` pages backward through history.

GET/api/explorer/block/{height|hash}?tx_offset&tx_limit

Full block record: header, paginated transactions, and every shadow event anchored to the block.

GET/api/explorer/tx/{txid}?vin_offset&vin_limit&vout_offset&vout_limit

Transaction with prevout-resolved inputs and spentness where provable; unknowables stay null, never guessed.

GET/api/explorer/address/{address}?offset&limit&shadow_offset&shadow_limit

Base-chain activity within disclosed coverage plus the complete synthetic payout history with independent pagination.

GET/api/explorer/shadow/tx/{synthetic_txid}

Synthetic payout record: lifecycle state, maturity, demurrage facts, spend linkage.

GET/api/explorer/shadow/supply

Anchored shadow supply: pools, materialized and phase-locked totals, claim counts.

GET/api/explorer/events

Recent shadow events (claims, distributions, signals) from the sanitized public stream.

GET/api/explorer/analytics/leaderboard?limit=1..100

Addresses ranked by materialized payouts, with PoW/PoS split and active range.

GET/api/explorer/analytics/series?from=<height>&to=<height>

Bucketed per-block series (payout value, event counts) for charting, capped at 240 points.

GET/api/explorer/search?q=<height|hash|txid|address>

Classifies a query and returns the exact explorer path for it.