---
id: FLEX-WP-0014
type: workplan
title: "Authorize tenant-engine guardrail actions"
domain: infotech
repo: flex-auth
status: finished
owner: grok
topic_slug: netkingdom
planning_priority: P1
planning_order: 140
depends_on_workplans:
  - FLEX-WP-0010
  - FLEX-WP-0013
related_workplans:
  - TEN-WP-0006
created: "2026-08-16"
updated: "2026-08-16"
state_hub_workstream_id: "7de17bd2-5e7c-5355-ba1d-40a051a67746"
---

# FLEX-WP-0014 - Authorize tenant-engine guardrail actions

Extend package `tenant-engine.write-api.mutate` from seven actions to nine
with the TEN-WP-0006 guardrail surface. Until they exist here, every
guardrail check resolves to `deny` `unknown_action` — correct fail-closed
behaviour, but the surface is inert.

**Requested by:** `tenant-engine` (TEN-WP-0006, message `5572d198`).
**Blocked on:** FLEX-WP-0013 (four-action production pin). That restore is
done; this workplan starts on a current seven-action package, not a
rolled-back one.

## Requirements from tenant-engine

Two new actions, both on resource type `guardrail`, both against
`system: "tenant-engine"`:

| Action | Resource type | HTTP surface |
|---|---|---|
| `tenant.guardrail.read` | `guardrail` | `GET /tenants/{id}/guardrails?actor=` |
| `tenant.guardrail.set` | `guardrail` | `PUT` / `DELETE /tenants/{id}/guardrails/{limit_key}` |

Strings are live in `tenant-engine/src/tenant_engine/authz.py`
`_RESOURCE_TYPES`. Match them verbatim. `CheckRequest` shape is unchanged:
`subject_type: "service"`, `resource_id` = `tenant_id`.

They are two actions so policy can grant a PDP the read without granting
the write. tenant-engine's own tests call the read as `actor=flex-auth`.

`v1` stays the activated revision; the identifying fact is that `v1` as of
this commit contains the two guardrail actions.

Do **not** deploy a new production image in this workplan until the package
is verified locally. Image + pin is a follow-on, named in T04.

## T01 - Extend the policy package with the guardrail actions

```task
id: FLEX-WP-0014-T01
status: done
priority: high
state_hub_task_id: "34fb239a-7f06-5e96-9f10-a6bbb85bf4c3"
```

Add `tenant.guardrail.read` and `tenant.guardrail.set` to
`valid_actions`, the frontmatter `actions:` list, and
`protected_system_manifest.yaml`. Add resource type `guardrail`.

CARING: `View` for the read (already used by qonto-assistant), `EditAny`
for the set (already used by `tenant.update`). Extend
`caring.capabilities` with `View`.

Register `flex-auth` as a second service subject that is allowed
`tenant.guardrail.read` and nothing else. Update `subject_manifest.yaml`
and rebuild `examples/tenant-engine/registry_snapshot.json`.

Update `docs/tenant-engine-action-vocabulary.md` and
`docs/tenant-engine-resource-namespace.md`. Keep the existing note that
this policy governs who may call tenant-engine's admin API, not a tenant's
own capability roles.

Done when `valid_actions` carries all nine actions, the new resource type
is declared, and `flex-auth` is a registered read-only subject.

Done 2026-08-16: nine actions in frontmatter, `valid_actions`, and the
protected-system manifest. Resource type `guardrail` added. CARING
`View` on the read, `EditAny` on the set. `flex-auth` registered as a
read-only subject. Registry snapshot rebuilt (2 subjects, 2 groups).

## T02 - Decide how the read/write split is used today

```task
id: FLEX-WP-0014-T02
status: done
priority: medium
state_hub_task_id: "8ea87d5f-883a-5d63-89bb-33a3d0963472"
```

tenant-engine split the actions so a PDP can read ceilings without being
able to change them. Decide whether that split is used now or only reserved.

Record the decision in `policy_package.md`. Using it now — `flex-auth` may
read, `tenant-engine` may read and set, nobody else — is the expected
outcome unless a concrete reason says otherwise. Inventing an `ops` write
subject is out of scope; writes stay on the existing service identity.

Done when the decision and its reasoning are recorded and implemented.

Done 2026-08-16: **yes — use the split now.** Recorded under "Decision:
use the read/write split now" in
`examples/tenant-engine/policy_package.md`. `flex-auth` may
`tenant.guardrail.read` and is denied `action_not_granted` on
`tenant.guardrail.set`. `tenant-engine` may do both. No `ops` write
subject.

## T03 - Fixtures and verification

```task
id: FLEX-WP-0014-T03
status: done
priority: high
state_hub_task_id: "1029d2ce-bb37-530e-91ef-ded86f6f5be8"
```

Add fixture pairs for: authorized `tenant-engine` read and set → allow;
authorized `flex-auth` read → allow; `flex-auth` set → deny
`action_not_granted`; unknown subject → deny `unknown_subject`; misspelled
guardrail action → deny `unknown_action`.

Verify against the real binary: `test-policy`, `load-registry`, `check` on
standalone request files. Then close the loop with a live `flex-auth serve`
and a real `tenant-engine` on `TENANT_ENGINE_FLEX_AUTH_URL`, through
unmodified `FlexAuthWriteAuthorizer`:

- `GET /tenants/{id}/guardrails?actor=flex-auth` → 200
- `GET ...?actor=ops` → 403
- `PUT ...` as `actor=tenant-engine` → 200
- `PUT ...` as `actor=flex-auth` → 403
- `PUT ...` as `actor=ops` → 403

Done when those five calls match, `go test ./...` is green, and
`gofmt`/`go vet` are clean.

Done 2026-08-16: 17/17 Rego tests, 23/23 fixtures. `load-registry` loads
clean. Standalone `check` files return the expected allow/deny.

Live `flex-auth serve` on `127.0.0.1:9098` + real `tenant-engine` on
`TENANT_ENGINE_FLEX_AUTH_URL`:

| Call | tenant-engine | flex-auth |
|---|---|---|
| `POST /tenants` actor=`tenant-engine` | 201 | allow |
| `GET .../guardrails?actor=flex-auth` | 200 `spend.monthly=25000` grouping | allow |
| `GET ...?actor=ops` | 403 `write_denied` | deny `unknown_subject` |
| `PUT .../spend.monthly` actor=`tenant-engine` | 200 override `9000` v2 | allow |
| `PUT ...` actor=`flex-auth` | 403 `write_denied` | deny `action_not_granted` |
| `PUT ...` actor=`ops` | 403 `write_denied` | deny `unknown_subject` |

`go test ./...` green; `gofmt -l` empty; `go vet ./...` clean.

## T04 - Closure and handoff

```task
id: FLEX-WP-0014-T04
status: done
priority: low
state_hub_task_id: "b2b44215-ef08-5c50-b466-190156a88ef3"
```

Confirm T01–T03. Notify `tenant-engine` naming the policy revision. State
plainly whether the nine-action package is **in source** or **deployed** —
FLEX-WP-0010 taught that distinction the hard way. Production rollout of a
new image is not implied by this workplan; it is a separate pin after CI
publishes a digest.

Done when the handoff is sent and this workplan is `finished`.

Done 2026-08-16: T01–T03 confirmed. Policy revision for the handoff is
package `tenant-engine.write-api.mutate` **version `v1`**, now carrying
all nine actions. The version string is unchanged because the package is
additive.

**In source, not in the cluster.** Production `flex-auth-tenant-engine`
still serves `sha256:9320df39` (seven actions). A CI-built image from
this commit plus a pin of `flex-auth-tenant-engine` is the remaining
step before a live guardrail check succeeds against the cluster Service.
tenant-engine's own TEN-WP-0006 surface is also not deployed, so the
cluster path is not yet the binding one.

Deployed 2026-08-16 after operator "sync and commit / deploy flex-auth":
CI image `main-f304688` /
`sha256:1bf060e61122693ce98359c167cc5fe8bdafc84e097e090eaa71af94d0f27cbc`
is live on `flex-auth-tenant-engine`. Approval
`8d1efcea-93c7-436b-a749-e5d464e94a33`. Rollback target remains
`sha256:9320df39`. `flex-auth-user-engine` stayed on `sha256:1f529037`.

Live `/v1/check` against the Service:

| Request | Effect | Decision |
| --- | --- | --- |
| `tenant.create` | allow `write_api_policy_matched` | `decision:ef18e8bbd2dead6a` |
| `tenant.retire` | allow `write_api_policy_matched` | `decision:996663f6902d0762` |
| `tenant.guardrail.read` as flex-auth | allow `write_api_policy_matched` | `decision:9b9e540de13cf7cf` |
| `tenant.guardrail.set` as tenant-engine | allow `write_api_policy_matched` | `decision:20c82bc38501a343` |
| `tenant.guardrail.set` as flex-auth | deny `action_not_granted` | `decision:a057a7030df65208` |
| misspelled guardrail | deny `unknown_action` | `decision:18ae70a79c6d47c6` |
| unknown subject | deny `unknown_subject` | `decision:a98c59c6a34f84ad` |
| misspelled lifecycle | deny `unknown_action` | `decision:1b3012abb4e2b27d` |

TEN-WP-0007 can pin the tenant-engine guardrail image. The seven
pre-existing actions still allow.