SF2X is the trust app for AI: an open, auditable attestation format and API. Every answer attested is decomposed into atomic claims, independently source-grounded, scored against domain-specific calibration, and signed. Businesses attest, suppress, and re-validate trust over time — so AI output carries a verifiable warrant, not a promise.
| Field | Type | Description |
|---|---|---|
| warrant_id | string | Globally unique warrant identifier. |
| answer_version_id | string | The attested answer this warrant backs (lineage id). |
| premises | string[] | Explicit premises the conclusion depends on. Empty premises invalidate a warrant. |
| conclusion | string | The warranted conclusion being attested. |
| confidence_score | number (0–1) | Independent verifier confidence given the premises. |
| validity_status | enum | valid = well-supported; weak = mixed; invalid = unsupported/fabricated; expired = premises stale. |
| sources | string[] | Cited sources — independently checked during attestation. |
| expiry_date | ISO-8601 datetime | When premises must be revalidated. |
| signed_hash | string | HMAC-SHA256 attestation over (answer|premises|sources). Verifiable by anyone holding the SF2X attestation key. |
{
"warrant_id": "w_8f3...",
"answer_version_id": "av_2c1...",
"premises": [
"Aspirin inhibits platelet aggregation.",
"Primary-prevention benefit in low-risk adults is small and outweighed by bleeding risk."
],
"conclusion": "A 52-year-old with no cardiovascular history should not routinely take daily low-dose aspirin for primary prevention.",
"confidence_score": 0.82,
"validity_status": "valid",
"sources": ["USPSTF 2022 recommendation", "NEJM meta-analysis 2019"],
"expiry_date": "2026-09-01T00:00:00.000Z",
"signed_hash": "sf2x_sig_dG9iZUV4YW1wbGU..."
}Find each function's URL under Dashboard → Code → Functions. Replace $FUNCTION_URL with your provisioned endpoint.
Inbound attestation. Submit an answer + optional premises/sources; returns verdict, trust, claims, signed warrant.
curl -X POST $FUNCTION_URL/warrantApi \
-H "Content-Type: application/json" \
-H "x-api-key: $SF2X_API_KEY \
-d '{ "answer_text": "...", "premises": [], "sources": [], "domain": "medicine", "stakes": "high", "model_label": "gpt-5" }'Attest up to 25 answers at once. Per-item results returned in order.
curl -X POST $FUNCTION_URL/batchWarrant \
-H "Content-Type: application/json" \
-H "x-api-key: $SF2X_API_KEY \
-d '{ "answers": [{ "answer_text": "...", "domain": "finance" }, ...] }'Re-check a previously attested answer against the live web. Detects drift, logs corrections, downgrades stale warrants.
curl -X POST $FUNCTION_URL/revalidateWarrant \
-H "Content-Type: application/json" \
-H "x-api-key: $SF2X_API_KEY \
-d '{ "answer_version_id": "av_2c1..." }'Free, keyless lookup. Returns the trust scorecard for any lineage id — publish it anywhere.
curl -X POST $FUNCTION_URL/trustScorecard \
-H "Content-Type: application/json" \
-d '{ "answer_version_id": "av_2c1..." }'Callable suppression gate. Returns allow / escalate / suppress for a lineage id so low-trust answers never reach users.
curl -X POST $FUNCTION_URL/gateApi \
-H "Content-Type: application/json" \
-H "x-api-key: $SF2X_API_KEY \
-d '{ "answer_version_id": "av_2c1..." }'