A receipt for what an agent actually did.
When agents transact — pay, book, sign, subscribe — the contested question is always: what was agreed, by whom, and when? Dynamic Feed is the neutral witness beside the transaction. It signs, timestamps with a two‑sided Bitcoin window, transparency‑logs and lets any party verify a record of the deal — without ever touching the money. A receipt rail, not a payment rail.
One call → a receipt no one can forge or back-date.
Hash the record
The agent computes a sha256 of its transaction record and (optionally) co‑signs that hash with its own key — proof of which agent attested.
We witness it
POST /v1/witness. Dynamic Feed verifies the agent's signature, signs the record itself, and drops it in a permanent append‑only hash‑chain. We see only a hash if you want — never your money, never PII.
Pinned in time
The receipt embeds a recent Bitcoin block hash (it couldn't exist before that block — a NOT‑BEFORE bound), and the log head is anchored to Bitcoin daily (EXISTED‑BY bound). A provable window no party controls.
Anyone verifies
Buyer, seller, insurer, auditor — each re‑checks the Ed25519 signature against our public key, with no trust in Dynamic Feed or each other.
Disputes settle on facts
"You take responsibility for what your agent buys" stops being he‑said/she‑said. There's a signed, timestamped, independent record of exactly what happened.
Beside every rail
Stripe, x402, AP2 move the value; the witness sits alongside and records it. Every payment rail becomes a place a receipt gets made — not a competitor.
Don't take our word — verify a receipt.
This fetches a real, signed sample transaction‑receipt from Dynamic Feed and verifies its Ed25519 signature in your browser against the published key. Then flip one byte and watch it fail — tamper‑evidence, demonstrated, not asserted.
curl -s https://dynamicfeed.ai/v1/witness -H "X-API-Key: $KEY" \ -H "Content-Type: application/json" \ -d '{"content_hash":"<sha256 of your txn record>","parties":["agent:buyer","agent:seller"],"txn_ref":"order-123"}'
A witness — never a money-mover.
Dynamic Feed is a neutral witness that sits outside the value path — it never accepts, holds, routes, converts or custodies funds, and holds no key that releases money. It only ever signs + timestamps + anchors a hash of a record you give it. A receipt proves that record existed at a time and hasn't been altered since (tamper‑evident, verifiable against our public key), and — if co‑signed — which agent key attested. It does not prove the transaction was authorized, correct, lawful, completed, or that any value moved. Provenance, not truth. This is data and evidence, not financial, legal or settlement advice.
Be underneath the agent economy.
Every machine-to-machine transaction needs a record someone can verify. Keyless to read + verify, a free key to witness.