Concepts and vocabulary

Stratl uses a small, fixed vocabulary on purpose. The same word means the same thing in the portal, the API, the record and the verifier’s output. Here they are, roughly in the order you meet them.

The things being recorded

Decision. One unit of AI-influenced work that affected one subject. A refund, a claim determination, a loan decline, a server restart. A decision has a beginning, a sequence of events and an outcome, and it gets exactly one record.

Subject. The person or thing the decision was about: a claim, an applicant, an order, a server. Every record is filed under its subject, so “everything about applicant 72819” is one query, not a search across systems. A subject has a type and an id, and optionally a display name.

Agent. The software that made or carried out the decision: “claims-triage”, “support-bot”. It has an id, and optionally a name, version and owner.

Event. One observable fact within a decision, numbered in order. There are eight types, and no others: input, retrieval, model_call, tool_call, policy_eval, approval, action, outcome. Each is explained here.

Actor. A participant in the decision: the agent itself, a system, or a human. A human actor carries an id (usually an email), a role such as “support_lead” or “medical_director”, and the identity provider that vouched for them, such as “okta”.

Outcome. How the decision ended for the subject, and whether it was adverse, meaning it went against the person. Adverse outcomes are what trigger notices and reconsideration rights under most frameworks.

What makes a record trustworthy

Fingerprint. A SHA-256 hash of some content, written as sha256: followed by 64 hex characters. Stratl records fingerprints of prompts, answers, documents and tool payloads, never the content itself. Anyone who holds the original can recompute the fingerprint and prove it is the same bytes; nobody can recover the content from the fingerprint.

Original content, or artifact. The actual bytes behind a fingerprint, if the source chose to send them. They go to custody storage under their fingerprint, never into the search index. The bundle carries them so a reader can re-hash them against the record.

Record hash. The fingerprint of the whole record, computed over a canonical form so that every implementation, in every language, gets the same answer. How it is computed.

Signature. Proof that the record was produced by the holder of one specific key, and has not changed since. Stratl uses ES256, the same algorithm as in web tokens and passkeys. The key lives in a key service and cannot be exported.

Key id. A short identifier for a public key, derived from the key itself (an RFC 7638 thumbprint). Every record names the key that signed it, so records stay verifiable after a key changes.

Chain. Every record in a workspace carries the hash of the record before it and its position number. Remove a record from the middle and the chain no longer links. This is what makes “nothing was quietly deleted” checkable.

Checkpoint. Every hour, or every thousand records, the custodian signs a single summary (a Merkle root) of all records not yet covered by a checkpoint and has it dated by an outside party. A checkpoint proves the set was complete and existed by that time.

Timestamp authority. An outside service, following the RFC 3161 standard, that dates a checkpoint. It is neither the customer nor Stratl, which is the point: it is the one fact about the evidence that Stratl could not fabricate. Stratl uses two, tried in order.

Assurance. How the events were captured: observed (a tracer or SDK saw them happen), attested (a system vouched for them), enforced (the action could not have happened without passing through the recording step). Stratl never upgrades assurance; a connector that only observes says “observed”.

Custody. Who holds the storage and the signing key: stratl (managed by Stratl in a region you chose) or customer (your own bucket and key on your own cloud). Every record says which. Custody explained.

Provenance. Where a record came from: the source (an SDK, OpenTelemetry, Langfuse, the Anthropic Compliance API), the source’s own ids, the connector version and when it was ingested.

What Stratl hands over

Evidence bundle. A zip for one decision: the signed record, the public key, any original content, the checkpoint that covers it, a manifest listing every file’s fingerprint, and instructions. Verifies offline. Details.

Subject pack. Every bundle about one person, every notice sent to them and the holds that apply, in one archive with a manifest signed by the workspace key. Built for data-subject requests. Details.

Period pack. A report over a date range against one framework, listing which controls each record’s evidence supports and which gaps exist, with a signed manifest. Details.

Framework pack. A YAML file mapping a regulation’s controls to the record fields that support them. Six ship today. Packs never claim compliance.

Notice. A plain-language letter to a person affected by an adverse decision, drafted from the record so every sentence cites the field it came from, approved by a named person, sent, and recorded. Lifecycle.

Reconsideration. A human review of a decision, recorded as its own signed record linked to the original.

Workflow record. Stratl’s own actions, written as records into your stream: a notice approved, a notice sent, a hold placed, custody transferred, the key used. Everything Stratl does to your evidence is itself evidence.

People and access

Workspace. A company’s private space: its own key, chain, records, sources, members and settings. Nothing crosses workspaces; a record from another workspace answers as if it did not exist.

Roles. Owner, admin, engineer, auditor. Owners and admins run the workspace, engineers connect things, auditors read everything and change nothing. The matrix.

Ingest key. A write-only API key for agents and collectors, shown once, stored as a hash. It can write records and upload originals, and read nothing.

Retention policy and legal hold. How long a workspace keeps records before they may be deleted, and a flag on a decision or a subject that blocks deletion whatever the policy says. Stratl never deletes anything itself. Details.

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