Perseus Ledger

Vault remembers. Ledger proves. Hermes executes.

Perseus Ledger is the verifiable event and provenance layer for autonomous systems. It records what happened, under what authority and evidence, and whether the history can be independently verified.

It is deliberately not an AI-spend dashboard. Hermes Cloud already provides Spend Intelligence for usage, tokens, funding, caps, and model-level cost analysis. Ledger complements that view with an append-only, hash-chained record that ties AI activity to the actor, boundary, evidence, configuration, action, result, and optional resource allocation behind it.

What Ledger establishes

For each recorded event, the stable ledger captures the operational facts already available to the system:

• Actor and boundary — organization, workspace, user/agent, and task type
• Execution configuration — provider, model, and event metadata
• Action and result — the event itself plus its immutable record hash
• Resource allocation — optional token and cost attribution
• Evidence linkage — external references and retained checkpoints where supplied
• Integrity — an append-only cryptographic hash chain that can be verified independently

The current ingestion contract is deliberately stable during the product transition: plutus_agent, the plutus CLI, /v1/usage, existing database paths, and deployed integrations remain supported compatibility surfaces. Stripe is an optional settlement adapter, not the product boundary.

Why it matters

AI systems need more than observability. They need a defensible answer to:

What did the system know, what did it do, under which model and policy, what did it consume, and can we prove it later?

Perseus Ledger provides the evidentiary layer for that answer. It can work beside Hermes Cloud, other agent frameworks, internal tools, offline environments, and federated deployments.

DoD and regulated-data relevance

• AI assurance: reconstruct a recommendation from the configuration, sources, actions, and evidence available when it was made.
• Program and cost-data curation: preserve source-to-output lineage, validation flags, analyst adjudications, and reproducible audit trails.
• Autonomous / distributed operations: retain a verifiable record of agent state, tool activity, and resource allocation for post-operation review.
• Governance: keep the human approval, correction, and policy context associated with consequential automated activity.

This is a product and architecture position, not a claim of handling CUI or satisfying a particular compliance regime.

Architecture boundary

Component	Question it answers
Hermes Cloud Spend Intelligence	What did we spend and use?
Perseus Ledger	What happened, under what authority and evidence, and can we prove it?
Perseus Vault	What durable, time-valid knowledge did the agent have?
Hermes Agent	What work did the agent execute?

Quick start: record a verifiable event

pip install plutus-agent  # compatibility package name during transition
plutus demo
# → opens the local Ledger console on http://localhost:8420

from plutus_agent import Meter

ledger = Meter(org="Acme Autonomous Systems")
ledger.track(
    provider="anthropic",
    model="claude-opus-4-8",
    task_type="evidence_review",
    workspace="mission-analysis",
    input_tokens=8200,
    output_tokens=2400,
)

This writes an immutable event into the local SQLite-backed hash chain. Existing hosted ingestion continues to use POST /v1/usage; refer to the API reference for the compatibility contract.

Integrity verification

Ledger integrity is not a marketing assertion. It is checked from the recorded chain and can be exposed through the existing admin verification endpoint in a controlled deployment.

• Ledger integrity
• API reference
• Schema
• Reconciliation — optional provider-cost and Stripe settlement reconciliation

Transition principles

1. No broken integrations. Package names, CLI commands, state paths, /v1 routes, deployed domains, and existing keys remain stable until a separately announced migration.
2. No competing dashboard. Hermes Cloud owns spend intelligence. Ledger surfaces integrity and evidence, not a replacement analytics product.
3. No billing-first story. Resource allocation and Stripe reconciliation remain supported adapters beneath the ledger.
4. Evidence before claims. The product must only claim provenance fields it actually records and can verify.

License

MIT — see LICENSE. © Perseus Computing LLC.