@vohlsyr/plugin-concordance

ElizaOS plugin for Concordance -- cross-source search and claim corroboration across 18 independent, real-time data sources (news, SEC filings, court opinions, economic indicators, market data). Every result cites its real source, never a black-box summary.

Paid per call via x402 -- USDC on Base, straight from the agent's own wallet. No API keys, no signup.

Actions

SEARCH_CONCORDANCE

Full-text search across all 18 sources. ~$0.01/call.

"search concordance for the Fed's latest rate decision"

CHECK_CORROBORATION

Checks whether a claim is backed by multiple independent sources or just one -- use this before treating something as verified. ~$0.04/call.

"is it true that the company missed earnings estimates?"

Setup

npm install @vohlsyr/plugin-concordance

Add to your character/project's plugin list, and set one secret:

EVM_PRIVATE_KEY=0x...   # a wallet funded with a small amount of USDC on Base

This is the same setting name ElizaOS's own @elizaos/plugin-evm uses, so an agent that already has a funded wallet configured for other on-chain actions picks it up automatically -- no second key to manage.

How it works

Every call follows the x402 protocol directly, with no custom auth or billing layer to integrate:

1. The action calls the real Concordance endpoint (e.g. POST /tools/search).
2. The server responds 402 Payment Required with the price and payment details.
3. x402-fetch signs and attaches a payment using the agent's wallet, and retries the request.
4. The server settles the payment and returns the real result.

Development

npm install
npm run typecheck
npm test        # vitest -- mocks the x402-fetch boundary, exercises real
                 # request-building/response-parsing/formatting logic
npm run build

The plugin also bundles a zero-cost elizaos test case (concordance plugin sanity) that pings Concordance's free /healthz endpoint to confirm the service is actually reachable -- no wallet or payment required for that one.

License

MIT