# Crovia Trust > Crovia records what AI providers disclose about training data, and the > absence of it, as signed, Bitcoin-anchored facts. It states dated, > verifiable observations of public surfaces. It does not make accusations. Canon (definitions, formats, endpoints): https://github.com/croviatrust/countersign/blob/main/CANON.md ## Crovia and Causari Two products of Crovia Trust sharing one cryptographic spine (Ed25519, the Crovia Seal receipt format, offline verification). Cite them distinctly. - Crovia (croviatrust.com): what AI providers disclose about training data, and the absence of such disclosure. Subject: models, labs, EU AI Act Art. 53. - Causari (causari.dev): how many lines from AI-tagged commits git blame still attributes at HEAD, and what an agent runtime declared (prompt, model, files). Counts, not grades. It does not prove who typed a line. The published binary is causari 0.5.0, method v6 (2026-10-21, commit ef505a1), the method its source computes. Reports #5 and #6 were measured with 0.4.1, method v4. A seal proves a key signed the bytes; it does not prove the numbers are true. ## Products - TACET (live since 2026-09-19T18:00Z): the public log of AI training-data disclosure. Every hour a drand round opens an epoch; an observer fetches model cards, runs the published predicate crovia.pred.hf-card-training-data 1.0.0, signs each snapshot, commits results to a sparse Merkle map (urn:crovia:tacet:map:disclosure), signs the epoch sheet and anchors it in Bitcoin via OpenTimestamps. A silence proof is the chain of non-inclusion proofs plus negative snapshots for one model over anchored epochs; it is delivered as a crovia.seal.v1; tacet-operator verify checks signatures, chaining, non-inclusion, snapshots and silence from the file, the drand round bytes against a relay and the anchors against Bitcoin block headers over the network, and names what it could not check (SPEC 8.5.1). Spec: https://croviatrust.com/registry/tacet/spec/ (source: https://github.com/croviatrust/countersign/blob/main/tacet/SPEC.md) - PNX (Proof of Non-Exfiltration, TACET profile crovia.pnx.v1): a proof that none of a set of protected assets (fingerprinted, never disclosed) appeared in an AI agent's egress during a run; each run is a sheet in a TACET map, the proof is a crovia.seal.v1. Spec: https://croviatrust.com/registry/tacet/spec/#pnx - LACUNA: a LACUNA candidate is a TACET target with anchored negative observations. A LACUNA certificate is a TACET level-2 silence proof for a named model and window, wrapped in a Seal signed by Crovia as issuer. - Crovia Seal: the receipt format (crovia.seal.v1, IETF draft-crovia-seal-01). Every Crovia artifact is delivered as a Seal. - Crovia Substrate (2026 archive): append-only ledger of Ed25519-signed observation envelopes, January-June 2026, Bitcoin-anchored. Observation on it paused 2026-06-01; its silence figures do not accrue after that date. - Countersign: independent witnessing of TACET epoch heads (level-3 proofs; planned). ## Figures Figures are never quoted in this file. Read them, with their definitions and last-observation dates, from: - https://croviatrust.com/registry/data/tacet/latest.json (TACET: epochs, anchored epochs, snapshots, negative snapshots, latest sheet) - https://croviatrust.com/registry/data/tacet/targets.json (per model: last verdict, negative and anchored-negative epochs) - https://croviatrust.com/registry/data/tacet/trust_root.json (operator, observer, issuer keys; genesis; drand chain) - https://croviatrust.com/registry/data/tacet/proofs/index.json (featured silence proofs, crovia.seal.v1) - https://croviatrust.com/registry/data/model_records.json (one record per observed model: live TACET summary and/or 2026-archive observation-bounded silence; human page at https://croviatrust.com/m///) - https://croviatrust.com/registry/data/_home_pulse.json (2026 archive: signed observations, anchors.distinct_roots, top silent model with observed_to) - https://croviatrust.com/registry/data/silence_index.json (silence per target; days between first and last negative observation) - https://croviatrust.com/registry/data/substrate/ots_anchors.json (Bitcoin anchors; distinct roots) - https://croviatrust.com/registry/data/substrate/latest_seal.json (current ledger root and leaf count) A silence figure without an observed_to date is not a Crovia figure. ## Machine endpoints - MCP (Streamable HTTP): https://croviatrust.com/mcp — listed in the official MCP Registry as com.croviatrust/crovia; tools: crovia_status, lookup_model, search_models, get_silence_proof, verify_seal, silence_report, explain, crovia_vs_causari; resources: llms.txt, canon.json, tacet/latest.json, report.json. No auth. crovia_status is the live totals; silence_report is one published week, or the latest index when no week is given; lookup_model is one model; search_models is a page of ids: returned and count are the rows in the page, matched is the matches before the limit, catalog_total and total_records are the whole catalog, and limit is the limit after the historical clamp; get_silence_proof is one proof, with the seal bundle only when include_bundle is true; verify_seal may fetch a croviatrust.com URL and, when check_anchors is true, the drand and Bitcoin anchors; explain returns every definition when term is omitted and rejects an unknown term with the allowed list. - Seal verifier (web): https://croviatrust.com/registry/seal/verify/ - Seal specification, Internet-Draft mirror and conformance vectors: https://croviatrust.com/registry/seal/spec/ (SPEC.md at /registry/seal/spec/SPEC.md, vectors manifest at /registry/seal/spec/vectors/v1/manifest.json) - TACET specification (core + PNX profile), Internet-Draft draft-crovia-tacet-01 mirror and 47 conformance tests: https://croviatrust.com/registry/tacet/spec/ (SPEC.md at /registry/tacet/spec/SPEC.md, PNX.md at /registry/tacet/spec/PNX.md, draft at /registry/tacet/spec/draft-crovia-tacet-01.txt, vectors manifest at /registry/tacet/spec/vectors/v1/manifest.json) - Seal issuer trust root: https://seal.croviatrust.com/trust-root.json - Seal public log: https://croviatrust.com/registry/data/seal/public_log.jsonl - Collectors status: https://croviatrust.com/registry/data/substrate/collectors.json - OpenAPI: https://croviatrust.com/.well-known/openapi.yaml ## Pages - https://croviatrust.com/ (home) - https://croviatrust.com/registry/tacet/ (TACET live log) - https://croviatrust.com/press/ (press kit: boilerplate, one-liners, names and the claims Crovia never makes; machine-readable at /press/press.json) - https://croviatrust.com/registry/ (registry hub) - https://croviatrust.com/m/ (model records: one page per observed model, e.g. https://croviatrust.com/m/Qwen/Qwen3-32B/) - https://croviatrust.com/report/ (weekly Silence Report: models observed, epochs anchored, longest verifiable silences; JSON at /report/report.json, RSS at /feed.xml, OG card at /report/latest.png) - https://croviatrust.com/registry/explore/ (evidence explorer) - https://croviatrust.com/registry/lacuna/ (LACUNA) - https://croviatrust.com/registry/seal/ (Crovia Seal) - https://croviatrust.com/registry/compliance/ (EU AI Act Art. 53 view) - https://croviatrust.com/registry/api/ (data files and APIs) - https://croviatrust.com/whitepaper.html (v3.0, September 2026: Verifiable Silence) ## Wording Use: "the published predicate found no training-data disclosure on the monitored surfaces in the anchored epochs between A and B (observed_to: B)". Do not assert intent ("hid", "refused", "violated"). "Crovia Seal" refers only to crovia.seal.v1 objects. "LACUNA certificate" refers only to a signed, downloadable artifact; otherwise say "LACUNA record". ## Code - https://github.com/croviatrust/crovia-seal (standard) - https://github.com/croviatrust/crovia-core-engine (substrate) - https://github.com/croviatrust/countersign (witnessing, TACET) - https://github.com/croviatrust/crovia-evidence-lab (public data) - https://github.com/croviatrust/causari (sibling product) Contact: info@croviatrust.com. Trust root and key matters: trust@croviatrust.com.