diff --git a/src/internal/adapters/tenantengine/adapter.go b/src/internal/adapters/tenantengine/adapter.go
new file mode 100644
index 0000000..eeb54b9
--- /dev/null
+++ b/src/internal/adapters/tenantengine/adapter.go
@@ -0,0 +1,74 @@
+// Package tenantengine calls tenant-engine's cache-read endpoint at
+// token-issuance time to source the optional tenant_roles claim
+// (net-kingdom/canon/standards/iam-profile_v0.3.md, "Tenant Roles").
+//
+// This is the cache-read direction only, and it fails OPEN -- the opposite
+// of flex-auth's live-lookup adapter (flex-auth/internal/adapters/tenantengine),
+// which must fail closed. tenant_roles is documented as a cache callers
+// must never trust for privileged decisions (flex-auth re-validates live
+// before authorizing aal2-class actions); losing this claim at issuance
+// time is a performance regression, not a security one. Blocking login
+// because a cache source is briefly down would be the wrong trade.
+package tenantengine
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+)
+
+// Client fetches cached capability roles for a tenant.
+type Client struct {
+	BaseURL string
+	HTTP    *http.Client
+}
+
+// New returns a tenant-engine cache-read client. A nil httpClient gets a
+// short default timeout -- this call sits on the synchronous token-issuance
+// path and must not turn a cache miss into a slow login.
+func New(baseURL string, httpClient *http.Client) *Client {
+	if httpClient == nil {
+		httpClient = &http.Client{Timeout: 2 * time.Second}
+	}
+	return &Client{BaseURL: strings.TrimRight(baseURL, "/"), HTTP: httpClient}
+}
+
+// Roles fetches GET /tenants/{tenantID}/roles.
+//
+// Returns (nil, false) -- not an error -- on any failure: unreachable
+// tenant-engine, non-200 response, or a malformed body. Callers must treat
+// false as "omit the tenant_roles claim entirely", never as "emit an empty
+// or stale role list".
+func (c *Client) Roles(ctx context.Context, tenantID string) ([]string, bool) {
+	if c == nil || c.BaseURL == "" {
+		return nil, false
+	}
+
+	url := fmt.Sprintf("%s/tenants/%s/roles", c.BaseURL, tenantID)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+	if err != nil {
+		return nil, false
+	}
+
+	resp, err := c.HTTP.Do(req)
+	if err != nil {
+		return nil, false
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, false
+	}
+
+	var body struct {
+		Roles []string `json:"roles"`
+	}
+	if err := json.NewDecoder(resp.Body).Decode(&body); err != nil {
+		return nil, false
+	}
+
+	return body.Roles, true
+}
diff --git a/src/internal/adapters/tenantengine/adapter_test.go b/src/internal/adapters/tenantengine/adapter_test.go
new file mode 100644
index 0000000..d437fd1
--- /dev/null
+++ b/src/internal/adapters/tenantengine/adapter_test.go
@@ -0,0 +1,107 @@
+package tenantengine_test
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"keycape/internal/adapters/tenantengine"
+)
+
+func TestRolesReturnsRolesOnSuccess(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/tenants/tenant:friendly:binky/roles" {
+			t.Fatalf("unexpected path %s", r.URL.Path)
+		}
+		w.Header().Set("Content-Type", "application/json")
+		w.Write([]byte(`{"tenant_id":"tenant:friendly:binky","roles":["CUS","VEN"]}`))
+	}))
+	defer server.Close()
+
+	client := tenantengine.New(server.URL, nil)
+	roles, ok := client.Roles(context.Background(), "tenant:friendly:binky")
+
+	if !ok {
+		t.Fatal("expected ok = true")
+	}
+	if len(roles) != 2 || roles[0] != "CUS" || roles[1] != "VEN" {
+		t.Fatalf("unexpected roles: %v", roles)
+	}
+}
+
+func TestRolesFailsOpenOnNon200(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusServiceUnavailable)
+	}))
+	defer server.Close()
+
+	client := tenantengine.New(server.URL, nil)
+	roles, ok := client.Roles(context.Background(), "tenant:friendly:binky")
+
+	if ok {
+		t.Fatal("expected ok = false on a 503")
+	}
+	if roles != nil {
+		t.Fatalf("expected nil roles, got %v", roles)
+	}
+}
+
+func TestRolesFailsOpenOnMalformedBody(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte("not json"))
+	}))
+	defer server.Close()
+
+	client := tenantengine.New(server.URL, nil)
+	_, ok := client.Roles(context.Background(), "tenant:friendly:binky")
+
+	if ok {
+		t.Fatal("expected ok = false on malformed body")
+	}
+}
+
+func TestRolesFailsOpenOnConnectionFailure(t *testing.T) {
+	client := tenantengine.New("http://127.0.0.1:1", nil)
+	_, ok := client.Roles(context.Background(), "tenant:friendly:binky")
+
+	if ok {
+		t.Fatal("expected ok = false on connection failure")
+	}
+}
+
+func TestRolesFailsOpenOnTimeout(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		time.Sleep(100 * time.Millisecond)
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte(`{"roles":[]}`))
+	}))
+	defer server.Close()
+
+	client := tenantengine.New(server.URL, &http.Client{Timeout: 10 * time.Millisecond})
+	_, ok := client.Roles(context.Background(), "tenant:friendly:binky")
+
+	if ok {
+		t.Fatal("expected ok = false on timeout")
+	}
+}
+
+func TestRolesFailsOpenOnNilClient(t *testing.T) {
+	var client *tenantengine.Client
+	roles, ok := client.Roles(context.Background(), "tenant:friendly:binky")
+
+	if ok || roles != nil {
+		t.Fatal("expected a nil *Client to fail open safely, not panic")
+	}
+}
+
+func TestRolesFailsOpenOnEmptyBaseURL(t *testing.T) {
+	client := tenantengine.New("", nil)
+	_, ok := client.Roles(context.Background(), "tenant:friendly:binky")
+
+	if ok {
+		t.Fatal("expected ok = false with an empty base URL")
+	}
+}
diff --git a/src/internal/server/oidc/token.go b/src/internal/server/oidc/token.go
index a830612..cd81f02 100644
--- a/src/internal/server/oidc/token.go
+++ b/src/internal/server/oidc/token.go
@@ -11,6 +11,7 @@ import (
 	"strings"
 	"time"
 
+	"keycape/internal/adapters/tenantengine"
 	"keycape/internal/domain"
 	profileerrors "keycape/internal/errors"
 	"keycape/internal/server/telemetry"
@@ -25,6 +26,9 @@ type TokenHandler struct {
 	Issuer        string
 	TokenLifetime time.Duration
 	Emitter       telemetry.Emitter
+	// TenantEngine sources the optional tenant_roles claim (KEY-WP-0005-T02).
+	// Nil disables it entirely -- token issuance never depends on it.
+	TenantEngine *tenantengine.Client
 }
 
 // tokenResponse is the JSON body returned on a successful token exchange.
@@ -130,12 +134,20 @@ func (h *TokenHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	// Core claims required by net-kingdom/canon/standards/iam-profile_v0.3.md
 	// for every production token -- not scope-gated, unlike the recommended
 	// human claims above (KEY-WP-0005-T01).
-	claims["tenant"] = effectiveTenant(user)
+	tenant := effectiveTenant(user)
+	claims["tenant"] = tenant
 	claims["principal_type"] = "human"
 	claims["groups"] = nonNilStrings(user.Groups)
 	claims["roles"] = nonNilStrings(user.Roles)
 	claims["assurance"] = assuranceClaim(sess.MFAVerified, now)
 
+	// Optional cached tenant_roles claim (KEY-WP-0005-T02). Fails open --
+	// see internal/adapters/tenantengine's package doc for why this is the
+	// one place in the whole tenant_roles design where that's correct.
+	if roles, ok := h.TenantEngine.Roles(ctx, tenant); ok {
+		claims["tenant_roles"] = roles
+	}
+
 	// 7. Sign JWT with RSA-SHA256.
 	kid := "key-1" // static kid for v0.1
 	jwtToken, err := buildJWT(claims, kid, h.SigningKey)
diff --git a/src/internal/server/oidc/token_test.go b/src/internal/server/oidc/token_test.go
index c6827f3..c088f65 100644
--- a/src/internal/server/oidc/token_test.go
+++ b/src/internal/server/oidc/token_test.go
@@ -14,6 +14,7 @@ import (
 	"testing"
 	"time"
 
+	"keycape/internal/adapters/tenantengine"
 	"keycape/internal/domain"
 	profileerrors "keycape/internal/errors"
 	"keycape/internal/server/oidc"
@@ -507,3 +508,117 @@ func TestTokenHandler_CodeDeletedAfterUse(t *testing.T) {
 		t.Errorf("second use: expected 400 (code replay), got %d", w2.Code)
 	}
 }
+
+// ---------------------------------------------------------------------------
+// KEY-WP-0005-T02: cached tenant_roles claim
+// ---------------------------------------------------------------------------
+
+func TestTokenHandler_TenantRoles_PresentWhenTenantEngineReachable(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		w.Write([]byte(`{"tenant_id":"tenant:coulomb","roles":["IAM","VEN"]}`))
+	}))
+	defer server.Close()
+
+	sessions := oidc.NewSessionStore()
+	users := &mockUserRepo{users: map[string]*domain.User{"alice": aliceUser()}}
+	h, _ := newTokenHandler(t, sessions, users)
+	h.TenantEngine = tenantengine.New(server.URL, nil)
+
+	verifier := "dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk"
+	code := seededSession(sessions, verifier)
+
+	params := url.Values{
+		"grant_type":    []string{"authorization_code"},
+		"code":          []string{code},
+		"client_id":     []string{"test-client"},
+		"redirect_uri":  []string{"https://app.example.com/callback"},
+		"code_verifier": []string{verifier},
+	}
+	req := tokenRequest(params)
+	w := httptest.NewRecorder()
+	h.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d (body: %s)", w.Code, w.Body.String())
+	}
+	resp := decodeTokenResponse(t, w.Body.String())
+	claims := parseJWTPayload(t, resp["id_token"].(string))
+
+	roles, ok := claims["tenant_roles"].([]interface{})
+	if !ok || len(roles) != 2 || roles[0] != "IAM" || roles[1] != "VEN" {
+		t.Errorf("tenant_roles: want [IAM VEN], got %v", claims["tenant_roles"])
+	}
+}
+
+func TestTokenHandler_TenantRoles_OmittedButIssuanceSucceedsWhenUnreachable(t *testing.T) {
+	sessions := oidc.NewSessionStore()
+	users := &mockUserRepo{users: map[string]*domain.User{"alice": aliceUser()}}
+	h, _ := newTokenHandler(t, sessions, users)
+	// Unreachable: nothing listens on this port.
+	h.TenantEngine = tenantengine.New("http://127.0.0.1:1", nil)
+
+	verifier := "dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk"
+	code := seededSession(sessions, verifier)
+
+	params := url.Values{
+		"grant_type":    []string{"authorization_code"},
+		"code":          []string{code},
+		"client_id":     []string{"test-client"},
+		"redirect_uri":  []string{"https://app.example.com/callback"},
+		"code_verifier": []string{verifier},
+	}
+	req := tokenRequest(params)
+	w := httptest.NewRecorder()
+	h.ServeHTTP(w, req)
+
+	// Token issuance itself must not fail just because the cache source is
+	// down -- this is the literal point of KEY-WP-0005-T02's fail-open rule.
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200 even with tenant-engine unreachable, got %d (body: %s)", w.Code, w.Body.String())
+	}
+	resp := decodeTokenResponse(t, w.Body.String())
+	claims := parseJWTPayload(t, resp["id_token"].(string))
+
+	if _, present := claims["tenant_roles"]; present {
+		t.Errorf("tenant_roles must be omitted (not null, not []), got %v", claims["tenant_roles"])
+	}
+	// Every other core claim must still be present -- one missing optional
+	// claim must not cascade into missing required ones.
+	for _, c := range []string{"tenant", "principal_type", "groups", "roles", "assurance"} {
+		if _, ok := claims[c]; !ok {
+			t.Errorf("required claim %q missing even though only tenant_roles should be affected", c)
+		}
+	}
+}
+
+func TestTokenHandler_TenantRoles_OmittedWhenTenantEngineNotConfigured(t *testing.T) {
+	sessions := oidc.NewSessionStore()
+	users := &mockUserRepo{users: map[string]*domain.User{"alice": aliceUser()}}
+	h, _ := newTokenHandler(t, sessions, users)
+	// h.TenantEngine left nil -- must not panic, must simply omit the claim.
+
+	verifier := "dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk"
+	code := seededSession(sessions, verifier)
+
+	params := url.Values{
+		"grant_type":    []string{"authorization_code"},
+		"code":          []string{code},
+		"client_id":     []string{"test-client"},
+		"redirect_uri":  []string{"https://app.example.com/callback"},
+		"code_verifier": []string{verifier},
+	}
+	req := tokenRequest(params)
+	w := httptest.NewRecorder()
+	h.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d (body: %s)", w.Code, w.Body.String())
+	}
+	resp := decodeTokenResponse(t, w.Body.String())
+	claims := parseJWTPayload(t, resp["id_token"].(string))
+
+	if _, present := claims["tenant_roles"]; present {
+		t.Errorf("tenant_roles must be omitted when TenantEngine is nil, got %v", claims["tenant_roles"])
+	}
+}
diff --git a/workplans/KEY-WP-0005-iam-profile-core-claims.md b/workplans/KEY-WP-0005-iam-profile-core-claims.md
index 1798298..f9e0114 100644
--- a/workplans/KEY-WP-0005-iam-profile-core-claims.md
+++ b/workplans/KEY-WP-0005-iam-profile-core-claims.md
@@ -4,7 +4,7 @@ type: workplan
 title: "IAM Profile core claims: tenant, principal_type, groups, roles, assurance, tenant_roles"
 domain: infotech
 repo: key-cape
-status: ready
+status: finished
 owner: codex
 topic_slug: netkingdom
 created: "2026-07-23"
@@ -139,7 +139,7 @@ human included.
 
 ```task
 id: KEY-WP-0005-T02
-status: todo
+status: done
 priority: high
 state_hub_task_id: "1b8f44b4-2763-4d5a-a3eb-1c2b9a25dd15"
 ```
@@ -165,11 +165,44 @@ Done when: token issuance still succeeds with `tenant_roles` omitted when
 `tenant-engine` is unreachable (test simulates the outage); present and
 correct when reachable, for a tenant with known role grants.
 
+**Done 2026-07-24:** New `internal/adapters/tenantengine` package
+(`Client.Roles(ctx, tenantID) ([]string, bool)`), mirroring
+`internal/adapters/{lldap,privacyidea,authelia}`'s shape exactly. Fails
+open by construction — unreachable, non-200, or malformed body all return
+`(nil, false)`, never an error the caller has to specially handle; a `nil
+*Client` also fails open safely rather than panicking, so `TokenHandler`
+doesn't need a separate "is this configured" branch. Wired into
+`TokenHandler.TenantEngine` (nil by default — existing tests and call
+sites are unaffected); `token.go` stamps `tenant_roles` only when `ok`.
+
+7 adapter-level tests (success, non-200, malformed body, connection
+failure, timeout, nil client, empty base URL). 3 new `token_test.go` cases
+prove the actual required behavior end-to-end through `TokenHandler`, not
+just at the adapter layer: present and correct when reachable; **token
+issuance still returns 200 with every other required core claim intact**
+when unreachable, `tenant_roles` simply absent (the literal done-criteria);
+absent when `TenantEngine` isn't configured at all. `go build`/`vet`
+clean, `go test ./...` green repo-wide.
+
+**A real bug found and fixed along the way, not worked around:** the first
+live cross-process check (real `flex-auth`, real `tenant-engine`, this
+adapter) returned `tenant_not_found` for a tenant that genuinely existed.
+`tenant-engine`'s `GET /tenants/{tenant_id}/roles` was keyed by its
+internal `tenant_id`, but `key-cape` (like any external caller) only ever
+has the tenant's profile *identifier* (the `tenant` claim value) — it has
+no way to know tenant-engine's internal id. Fixed at the source:
+`tenant-engine/workplans/ADHOC-2026-07-24.md` (identifier-or-id resolution
+added to `InMemoryTenantStore`), re-verified with the exact same live
+three-process chain afterward — `roles=[IAM] ok=true`, resolved by
+identifier. This is exactly why T02 insisted on a live-server-reachable
+test rather than only an `httptest` fake: the fake would have used
+whatever id shape the test author happened to pick and never caught this.
+
 ## Task: Closure review
 
 ```task
 id: KEY-WP-0005-T03
-status: todo
+status: done
 priority: low
 state_hub_task_id: "34555bf7-0f18-4dac-ade2-6ff3738f353f"
 ```
@@ -180,3 +213,33 @@ producing conformant tokens, and unblocks `flex-auth`'s side of the
 `tenant_roles` picture receiving a real claim to reason about (though
 `flex-auth`'s live-lookup path doesn't depend on this claim existing — only
 the cache-read/performance path does). Run `statehub fix-consistency`.
+
+**Closed 2026-07-24.** T01–T02 done. `go build ./...`, `go vet ./...` clean;
+`go test ./...` green across the whole repo. Python
+`net-kingdom/tools/iam-profile-conformance` not run against a live instance
+(needs the full Authelia+LLDAP+privacyIDEA stack, impractical in this
+pass) — real coverage instead came from `tests/profile`'s own full HTTP
+integration test (`TestCompleteTokenFlow`) with genuine claim-value
+assertions, and from three separate live cross-process checks against a
+real `tenant-engine` (one of which found and fixed a real bug in
+`tenant-engine` itself, `ADHOC-2026-07-24`).
+
+**What this closes:** `key-cape`'s human Authorization Code + PKCE flow now
+emits every IAM Profile v0.3 core claim (`tenant`, `principal_type`,
+`groups`, `roles`, `assurance`) plus the optional `tenant_roles` cache,
+correctly sourced from a real `assurance` signal (MFA actually verified
+this session, not static enrollment) and a real `tenant-engine` call
+(fail-open, never blocking login). `KEY-WP-0004`'s Binky onboarding can now
+produce conformant tokens for human logins.
+
+**What stays explicitly open, not silently dropped:**
+- `client_credentials` / service-token issuance — no such flow exists in
+  `token.go` at all yet (confirmed in T01); needed before any *service*
+  caller (not a human) can get a token with `principal_type: "service"` and
+  its own `tenant`/`tenant_roles`. A materially larger, separate piece of
+  work than either task in this workplan.
+- `flex-auth`'s side of `tenant_roles` (`FLEX-WP-0008`, already closed
+  separately) doesn't depend on this claim existing at all — its
+  live-lookup path calls `tenant-engine` directly, so this workplan doesn't
+  block it, but also doesn't complete the full `tenant_roles` picture on
+  its own until service tokens exist too.