NIST AI RMF

The NIST AI Risk Management Framework (AI RMF 1.0, published January 2023) is a voluntary framework organized around four core functions: Govern, Map, Measure, and Manage. This page documents how chio's shipped primitives map onto those functions and their subcategories. It is a mapping, not a certification claim.

The Four Functions

The RMF organizes controls into four functions. Chio contributes to each one differently. At a glance:

Chio's strongest contribution is to Map and Manage: capabilities, guards, receipts, and revocation are the tool-layer implementation of context identification, control cataloging, and risk response. Govern subcategories are largely organizational; chio contributes where policy-as-code and workload identity touch organizational artifacts. Measure is partially covered: chio emits the raw data but leaves risk scoring to the operator's analytics stack.

Coverage Legend

Function: GOVERN

Govern is primarily organizational. Chio aligns with the subcategories that describe signed policies, risk tolerance encoded as configuration, and lifecycle mechanics like decommissioning.

Function: MAP

Map is where chio's evidence posture shines. Every action produces a signed receipt. Every tool is described by a signed manifest. Every capability has typed constraints. The result is that the organization never has to reconstruct context after the fact.

Function: MEASURE

Measure asks for quantitative tracking of risks, mitigations, and outcomes. Chio emits the raw data: every invocation, every denial, every guard trigger, every cost event is a signed, queryable record. Scoring itself is left to the operator, because scoring requires taxonomy choices that are organization-specific.

Function: MANAGE

Manage covers prioritization, treatment, and post-deployment response. Chio's capability-plus-revocation model is precisely the primitive the Manage function needs at the tool boundary.

Evidence Collection Example

A common review question is: "show me the evidence that covers MAP-2.1 and MANAGE-2.2 for the past quarter." Chio gives that as a queryable bundle.

# Pull the signed manifest that defines the tool surface (MAP-2.1).
$ chio manifest verify \
    --manifest-file ./tool-manifest.json > manifest-verified.json

# Export the quarter's receipts for revocation activity (MANAGE-2.2).
$ chio receipts query \
    --since 2026-01-01T00:00:00Z \
    --until 2026-03-31T23:59:59Z \
    --kind revocation \
    --receipt-db ./receipts.sqlite3 > q1-revocations.json

# Bundle into an auditor-facing evidence envelope.
$ chio evidence export \
    --policy ./policy.yaml \
    --receipt-db ./receipts.sqlite3 \
    --include manifest-verified.json \
    --include q1-revocations.json \
    --output ./q1-rmf-evidence-bundle

The resulting bundle carries signed manifests, filtered receipts, and the embedded policy hash. An auditor can verify the bundle's signatures, verify each included receipt's checkpoint, and pull inclusion proofs for any subset of interest, without needing runtime access to the live kernel.

Gaps and Non-Goals

• Risk scoring: chio emits the raw data for MEASURE, but scoring is operator-owned.
• Residual-risk register: MANAGE-1.4 requires tracking residual risk. Chio does not model residual risk explicitly; operators build that register from receipt aggregates.
• Fairness, bias, environmental impact: MEASURE-2.9 through MEASURE-2.12 concern model-layer properties that a tool-governance layer cannot observe.
• Workforce-related Govern subcategories: roles, training, leadership commitment, and stakeholder culture are organizational and not implementable in code.

Cross-References

• Capabilities for the scoping model referenced in Map and Manage.
• Receipts for the evidence record format used by Measure.
• Guards for the named controls that implement Map-4.2.
• EU AI Act for the parallel mapping against Article 19 logging.