{"openapi":"3.1.0","info":{"title":"Hedera Topic API","version":"1.0.0","description":"Read the Hedera Consensus Service (HCS) live from the public Hedera mirror node — no key. HCS is Hedera's signature feature: a decentralized, ordered, timestamped message log that powers audit trails, supply-chain tracking, oracles and tokenization registries — the layer that account- and token-readers miss entirely. Look up any topic for its memo, admin/submit-key control, auto-renew and deleted state; read a topic's most recent messages, decoded from base64 to text, each with its consensus sequence number, timestamp and the account that paid to submit it; or discover the topics that are actively receiving messages right now. The consensus-messaging layer for Hedera wallets, explorers, dApps and auditors. Live from the mirror node; short cache only.","contact":{"name":"PremiumApi","url":"https://www.oanor.com/by/premiumapi"}},"servers":[{"url":"https://api.oanor.com/hederatopic-api","description":"oanor gateway"}],"tags":[{"name":"HCS"},{"name":"Meta"}],"components":{"securitySchemes":{"oanorKey":{"type":"apiKey","in":"header","name":"x-oanor-key","description":"Get your key at https://www.oanor.com/developer/keys"}}},"security":[{"oanorKey":[]}],"paths":{"/v1/messages":{"get":{"operationId":"get_v1_messages","tags":["HCS"],"summary":"A topic's recent decoded messages","description":"","parameters":[{"name":"id","in":"query","required":false,"description":"Hedera topic id (0.0.x); omit for the demo topic","schema":{"type":"string"},"example":"0.0.368908"},{"name":"limit","in":"query","required":false,"description":"Max messages (1-50)","schema":{"type":"string"},"example":"10"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"Most recent HCS messages on the topic (newest first), decoded from base64 to text where printable. Each has its consensus sequence number, timestamp and the account that paid to submit it.","count":10,"source":"Hedera mirror node","messages":[{"message":"1781424220160 UkyatXFBPDSPqOXVgMZUzlRpgBpyfwfrxExgqRlcqHEGDTZMIxHDhzUWpiqTJvGnnnsVYqzNHrRkugjlSiYGqVUTdCQxtQgadumWVPwNyPUJbEVbUYfMmlfIvJJoEUFqTFGLuRdYTEWomhBLBNxlXlGZQEubRXzUuxDieZlkMAAHDQtmirLvRZirBKQXurcxjVgfPTBIUXEEenVSwyAZvmfEwdAJyViLSJNpYeZWFOUeEDKttI","encoding":"utf8","size_bytes":256,"sequence_number":22614984,"payer_account_id":"0.0.256009","consensus_timestamp":"1781424220.839574000"},{"message":"1781424217624 UfDmswGqAxosZumgmiANUygUArmHtNiclHPeFCCZSrIoZDkiRpHiGCQYBcLdAtjojKyHzSjbngPIRyWVzZegEMxtZCeLgabFktxDcLAtqqCXOcBmpnZuIZZaBtGIafpFfGbCKZAENEdihJQwReixHsJUMSItzKnmZuajnYJMkDYZdmZLNdkieqFHdeBvPzIOWzZRmnyEMmOcDmiOeCduQoKDZMnPcHnbemqojsxWpdjEGyxnDc","encoding":"utf8","size_bytes":256,"sequence_number":22614983,"payer_account_id":"0.0.256009","consensus_timestamp":"1781424218.645812000"},{"message":"1781424210160 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