{"actions":[{"endpoint":"https://api.helloaigent.dev/v0/demo/actions/claim-offer","input_schema":{"$ref":"https://helloaigent.dev/schemas/demo-claim-offer-request.schema.json"},"name":"claim_offer"}],"body_markdown":"This envelope exists so independent implementations can verify signatures.\n","data":{"price_usd":41,"public_price_usd":50,"qty_available":200,"sku":"HA-MVP-001"},"feed":"hello-aigent-product","id":"msg_fixture0001","published_at":"2026-07-01T00:00:00.000Z","summary":"A deterministic envelope used to verify JCS canonicalization + Ed25519 signing.","title":"Fixture: agent-exclusive demo offer","type":"offer"}