AI Policy Enforcement

EVE enforces policy at the point of action. A proposed tool call, model action, or MCP request is evaluated against policy packs, and EVE returns a deterministic ALLOW, BLOCK, or MODIFY verdict before the side effect occurs.

How enforcement works

• Policy packs — CoreGuard evaluates requests against policy packs (27 packs ship in-tree covering domains such as lending, banking/AML, and PII handling), using deterministic threshold and rule functions.
• Three dispositions — ALLOW proceeds, BLOCK stops the action, MODIFY forwards only the modified request.
• Reason codes — every non-trivial disposition carries deterministic reason codes and a decision identifier.
• Fail-closed — if the governance service is unreachable, enforcement resolves to BLOCK or raises; there is no silent permissive fallback.

SDK example

from eve_coreguard import EVE

eve = EVE()

result = eve.govern_tool_call(
    tool="export_customer_pii",
    arguments={"format": "csv", "rows": 20000},
    context={"tenant_id": "org_abc", "principal_id": "svc_export", "session_id": "sess_44"},
)

match result["action"]:
    case "ALLOW":
        do_export()
    case "MODIFY":
        do_export()  # only the modified (forwarded) request proceeds
    case "BLOCK":
        log_blocked(result["reason_codes"])

Links

• Determinism guarantees: /seo/landing/deterministic-ai-governance.md
• Test candidate policies safely: /seo/landing/ai-policy-simulation.md
• Evidence for enforced decisions: /seo/landing/ai-compliance-evidence.md

Readiness

Policy enforcement via CoreGuard is PILOT_READY (128 CoreGuard tests passed). Fail-closed deployment across embedded, hosted, sidecar, MCP-gateway, and sovereign modes is PILOT_READY. The SDK core is a RELEASE CANDIDATE WITH EXCLUSIONS.

Limitations

• Enforcement covers the governance verdict; the governed application is responsible for actually gating on the returned action.
• The pip client enforces via hosted mode and requires a reachable endpoint; embedded enforcement is the EVE service.
• Standards mappings that accompany policy packs are descriptive; they are not a certification and do not by themselves make a system compliant with any framework.

Next step

Bring a policy set into a pilot and watch ALLOW / BLOCK / MODIFY decisions land on real requests with signed evidence.