THE BRAIN
OF THE OPERATION.

HCS-21 defines platform-agnostic adapter registries that give distributed appnets (Floras) their intelligence. Each adapter is a deterministic software package that achieves consensus about specific entity types.

READ SPECBUILD ADAPTER
THE DIFFERENCE

Adapters Make Floras Smart

HCS-16 ONLY

Empty Nodes

Without adapters, Flora nodes have no intelligence—just empty coordination.

HCS-16 + HCS-21

Active Adapters

Price Oracle
Processing consensus...
Agent Registry
Processing consensus...
Trust Signals
Processing consensus...

With HCS-21, each adapter brings deterministic intelligence to the Flora.

LIFECYCLE

How It Works

STEP 1

Publish Adapter

Developer publishes adapter package to npm/PyPI/crates.io and creates signed manifest

IN ACTION

Live Example: Flora Price Oracle

Active Adapters

Binance Adapter
$42,150
BTC/USD
Coinbase Adapter
$42,148
BTC/USD
Kraken Adapter
$42,152
BTC/USD
Consensus Reached

All three adapters agree on price range. Flora state hash: 0xb4c3...

MESSAGES

The Protocol

Adapter Declaration

adapter-declaration.json
cat adapter-declaration.json | jq .
{
"protocol": "HCS-21",
"adapter_id": "price-oracle-v1",
"manifest": "hcs://1/0.0.123456",
"package": "npm:@flora/[email protected]",
"entity_type": "price_feed"
}

Deterministic Consensus

Every Flora participant runs the exact same adapter version, ensuring reproducible state hashes via HCS-17. No more "it works on my machine" in distributed consensus.

Build Your First Adapter

Create deterministic adapters for any data source—agent registries, oracles, governance feeds—and plug them into any Flora.

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