Verdra · Security architecture

How an Evidence Package is signed and sealed.

Verdra Record's integrity model is designed so a Verdra Evidence Package is admissible and tamper-evident without requiring trust in Verdra. Capture happens inside the customer's environment; signing keys are customer-held; storage is customer-controlled WORM; tamper-evidence is content-addressed and time-stamped by an external authority.

In plain English

Three guarantees you don't have to take Verdra's word for: (1) the record is signed by your company's own keys, not Verdra's, so no one at Verdra can sign anything on your behalf; (2) the record lives in storage you own and lock down (an S3 bucket with retention rules, for example), so Verdra has no way to alter or delete it; (3) a third-party timestamping service stamps each record at the moment of capture, so neither Verdra nor you can backdate it after the fact (RFC 3161 timestamping is deferred in V0.1 and disclosed in each package as a forward commitment under Rules P.5).

The rest of this page is the technical version of those three guarantees, written for your security team.

1. Threat model

The system protects against four families of threat:

The integrity model places Verdra outside the trust boundary for record contents. The customer's keys sign; the customer's storage holds; an external timestamp authority countersigns at V1.0 (deferred in V0.1 as a forward commitment under Rules P.5); the schema and rulebook are public.

2. Capture flow

Single-action capture · client-side
1. Action dispatchagent runtime hook
SDK intercepts at runtime hook. No agent code change; instrument LangGraph, LangChain, AutoGen, CrewAI, Semantic Kernel, OpenAI/Anthropic/Google, or a custom runtime.
2. Strata captureS(a) S(b) S(c) S(d)
Four strata sealed in <25 ms: transaction, configuration, behavior, mandate. Configuration is captured by reference (prompt hash, tool inventory, model version) so the Evidence Package stays compact.
3. Content addressBLAKE3-256
Package gets a content-addressed identifier. Any modification produces a different ID; references that resolved at capture time fail to resolve if anything was changed.
4. Customer signaturecustomer-held keys
Customer-held key signs the package. Verdra never sees the private key; KMS integration via AWS KMS, GCP KMS, Azure Key Vault, or HSM at customer election.
5. RFC 3161 timestampexternal TSA · deferred in V0.1
External timestamp authority countersigns. RFC 3161 token from a third-party TSA establishes the record existed at the captured moment, independent of Verdra and of the customer's own time. Deferred in V0.1 and disclosed in each package as a forward commitment under Rules P.5; closes alongside V1.0 schema freeze.
6. WORM storagecustomer-controlled
·
Write-once storage. S3 Object Lock, GCS retention policies, Azure Blob immutability, on-prem WORM, or a customer-elected equivalent. Verdra has no write path.

3. Integrity primitives

Hashing BLAKE3-256 Content-addressed identifiers. Faster than SHA-256 with equivalent collision resistance; package ID is the BLAKE3 of the canonical-serialized package.
Signing Ed25519 (default) Customer-held signing keys. ECDSA P-256 with SHA-256 supported for FIPS 140-3 / NIST SP 800-186 bound environments. Signing happens in-process via KMS integration; private keys never leave the customer boundary.
Timestamping RFC 3161 (V1.0) External timestamp authority countersigns each package hash. Establishes tamper-evident time of existence independent of Verdra and the customer. Deferred in V0.1 and disclosed per package as a forward commitment under Rules P.5. TSA selection is customer-elected; batching policies (per-package vs. Merkle-batched) negotiated per engagement.
Storage WORM, customer-held Write-once-read-many storage chosen by the customer. AWS S3 Object Lock, GCS retention policies, Azure Blob immutability, or on-prem appliance.
Transport TLS 1.3 + mTLS Telemetry and operational signal transit over TLS 1.3. Customer-elected mTLS for endpoint authentication on inbound flows.
Schema Public & versioned Evidence Package schema is public, versioned per the Verdra Rules. Adjudicators of any venue can verify integrity without access to Verdra systems.

4. Behavior stratum: self-report vs. re-derived

S(c) Behavior captures what the agent would have done at decision time. Two collection modes are supported, and the mode used is recorded in the package itself:

Both modes carry the BLAKE3 root forward; an adjudicator can see which mode produced the S(c) row and weight it accordingly.

5. What Verdra cannot do

The architecture is designed so these claims hold without trusting Verdra in good faith:

6. Disclosure and engagement model

Production-stage deployments include a Data Processing Agreement scoping the customer/Verdra role under GDPR / Quebec Law 25 / CCPA, key-management responsibilities, retention defaults, and incident-notification windows. The DPA is shared at engagement; request the security packet for security-team review.

7. Roadmap

Forward commitmentsSOC 2 Type I and ISO 27001 tracks open when a first reference-implementation engagement substantiates the workload. Cross-implementation Evidence Package interoperability test suite (open source) targeted alongside Rules v0.2 (Q3 2026). Independent cryptographic review of the integrity model is part of any engagement scoping.

This page is a preview-stage description of Verdra Record's intended architecture. Specific control implementation, KMS integration patterns, and audit evidence are scoped per engagement.