Query and analyze Hedera HCS (Consensus Service) topics with AI-powered intelligence using GPT-4o Mini. Built for developers integrating blockchain message consensus into agents, with per-call HBAR billing.
io.github.mountainmystic/hedera-hcs-mcp-server
Local install
STDIO
4 required env vars
How models use it and what it is built for.
Query and analyze Hedera HCS (Consensus Service) topics with AI-powered intelligence using GPT-4o Mini. Built for developers integrating blockchain message consensus into agents, with per-call HBAR billing.
Local install — runs as a subprocess.
Configuration this server reads at startup.
Hedera account ID in format 0.0.XXXXXXX
Hedera account private key (ECDSA hex format)
Hedera network: testnet or mainnet
OpenAI API key for GPT-4o Mini powered analysis
Where to find authoritative docs and source for Mountainmystic Hedera Hcs.
Paste any of these into Agent Studio after connecting Mountainmystic Hedera Hcs.
Common questions about connecting and running Mountainmystic Hedera Hcs.
What is Hedera HCS and why would I use this MCP server?
Hedera Consensus Service (HCS) is a blockchain service for timestamped, ordered messages. This server lets AI agents query and intelligently analyze HCS topics in real time, useful for monitoring consensus data, extracting insights, or automating responses to on-chain messages.
How do I set up authentication for this server?
You need a Hedera account with HEDERA_ACCOUNT_ID (format 0.0.XXXXXXX) and HEDERA_PRIVATE_KEY (ECDSA hex format), plus OPENAI_API_KEY for GPT-4o Mini analysis. Set HEDERA_NETWORK to 'testnet' or 'mainnet' depending on your environment.
What are the costs of using this server?
The server charges per API call in HBAR (Hedera's native token). Exact pricing depends on Hedera's HCS query fees and OpenAI's GPT-4o Mini token usage; check Hedera's fee schedule and OpenAI pricing for current rates.
Can I test this on Hedera testnet before going to mainnet?
Yes. Set HEDERA_NETWORK to 'testnet' and use a testnet account ID and private key. This lets you validate your setup and prompts without spending mainnet HBAR.
What happens if my HEDERA_PRIVATE_KEY or OPENAI_API_KEY is invalid?
The server will fail to authenticate with Hedera or OpenAI and return an error. Ensure both keys are in the correct format (ECDSA hex for Hedera, valid OpenAI API key) and have appropriate permissions before connecting.
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