Promise get on the vault's seat, so the Go vault can serve it (issue 674)

The vault hands a secret only on request and reply, sealed to the asker's key
(hq ADR 0349 §11). The seat set is the controller's, so the verb is promised
here; optional until the vault that runs serves it (design 33 §7).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/catalogue/seats.go

@@ -128,7 +128,19 @@ var defaultSeats = append([]Seat{
 	// The vault: the controller seals every minted credential with what it provides, which is the
 	// test for a seat of the mesh's own (novox/hq ADR 0161) — a second provider of `secret` is a
 	// second claimant, refused by name, rather than a candidate for a pin.
-	{Name: "mesh-vault", Scope: ScopeMesh, Delivers: "secret", Decision: "novox/hq ADR 0161"},
+	//
+	// Its one verb, `get`, hands a secret on request and reply, sealed to the key the asker sends and only
+	// to an asker the vault allows (novox/hq ADR 0349 §11, issue 674). Optional until the vault that runs
+	// serves it (design 33 §7).
+	{Name: "mesh-vault", Scope: ScopeMesh, Delivers: "secret", Decision: "novox/hq ADR 0161",
+		Serves: []Verb{
+			{Name: "get", Optional: true, Description: "One secret, sealed to the public key the asker sends (the " +
+				"sealed box of ADR 0206), with its generation; answered only to an asker the vault allows, as the " +
+				"bus proved it. Never the value in the clear, and never to a private key.",
+				Input: schema(map[string]string{"name": "the secret's name",
+					"public_key": "the asker's X25519 public key as SPKI PEM — never a private key"},
+					[]string{"name", "public_key"})},
+		}},
 	// Named for its scope since 2026-09-30 (novox/hq ADR 0156); `the-artifact-store` resolves to it as
 	// an alias on a mesh that predates the rename. It serves artifacts of every kind a build makes —
 	// images and archives, by digest — which is why the provision is the artifact store and not an

internal/catalogue/vault_seat_test.go

@@ -23,3 +23,34 @@ func TestTheVaultsSeatDeliversSecret(t *testing.T) {
 		t.Fatal("a provider of secret that does not claim the seat was allowed to hold it")
 	}
 }
+
+// The vault answers `get` on request and reply (novox/hq ADR 0349 §11, issue 674): the seat promises the
+// verb, so a holder serving it is accepted — and, optional while the vault that runs is the TypeScript one,
+// so is a holder that does not yet.
+func TestTheVaultsSeatPromisesGet(t *testing.T) {
+	seat, _ := SeatNamed("mesh-vault")
+	var get *Verb
+	for i := range seat.Serves {
+		if seat.Serves[i].Name == "get" {
+			get = &seat.Serves[i]
+		}
+	}
+	if get == nil {
+		t.Fatal("the vault's seat does not promise get")
+	}
+	for _, arg := range []string{"name", "public_key"} {
+		if props, _ := get.Input["properties"].(map[string]any); props[arg] == nil {
+			t.Errorf("get takes no %s", arg)
+		}
+	}
+	serving := Manifest{Module: "mesh-vault", Provides: []Offer{{Name: "secret", Scope: ScopeMesh}},
+		Claims: []Claim{{Name: "mesh-vault", Scope: ScopeMesh, Serves: []string{"get"}}}}
+	if err := CanHold(serving, seat); err != nil {
+		t.Fatalf("the vault serving get was refused: %v", err)
+	}
+	notYet := Manifest{Module: "mesh-vault", Provides: []Offer{{Name: "secret", Scope: ScopeMesh}},
+		Claims: []Claim{{Name: "mesh-vault", Scope: ScopeMesh}}}
+	if err := CanHold(notYet, seat); err != nil {
+		t.Fatalf("the vault that does not serve get yet was refused: %v", err)
+	}
+}