diff --git a/README.md b/README.md
index 4109509..5d494ab 100644
--- a/README.md
+++ b/README.md
@@ -10,6 +10,11 @@ implements its contract, and no holder's code lives here.
 - **The definition**, written by hand: `seats/<seat>/seat.json`, its fixtures in `seats/<seat>/fixtures/`, and the
   parts several seats include whole in `parts/` (the four registry seats' verbs and events are `parts/registry.json`).
   mesh-sdk's `seatdef` is the one reader of the format; the indexer and the generators use it.
+- **A state**, in the definition's `states` (ADR 0608 §1, ADR 0634 §6): `{name, template, writer, key-forms, history,
+  max-age-days, description}`. `template` is one of ADR 0595's six (`state`, `events`, `work-queue`, `log`, `objects`,
+  `ledger`); `writer` is `holder` (the default) or `caller`; each key form is `{key, value, description}`, the key a
+  pattern of named parts between angle brackets (`<asker>.<id>`) and the value its JSON Schema. A definition names no
+  holder module: a reader takes the holder from its own manifest's `reads`. A fixture of a state is `state:<name>/<key>`.
 - **The seat set**, generated: `go/seats` (module `git.novox.be/novox/mesh-contracts/go`), every seat's name, scope,
   verbs and provision at the seat list's grain (ADR 0625 §2). mesh-sdk's `catalogue` is its only importer in mesh-sdk.
   A change of it rebuilds every importer of the seat set. Its npm package is `ts/` (`@novox/mesh-contracts`, the
diff --git a/format/seat-definition.schema.json b/format/seat-definition.schema.json
index 2c64151..3202f33 100644
--- a/format/seat-definition.schema.json
+++ b/format/seat-definition.schema.json
@@ -130,27 +130,11 @@
       },
       "description": "the holder's own events listed beside the seat, keeping the holder's subjects (ADR 0620 \u00a72)"
     },
-    "records": {
+    "states": {
       "type": "array",
+      "description": "the layouts of the state the holder keeps on the bus for the seat (ADR 0608 \u00a71, ADR 0634 \u00a76); a whole definition's. No holder module is named: each reader takes the holder from its own manifest's reads",
       "items": {
-        "type": "object",
-        "additionalProperties": false,
-        "required": [
-          "name"
-        ],
-        "properties": {
-          "name": {
-            "type": "string",
-            "pattern": "^[a-z][a-z0-9-]*$"
-          },
-          "key": {
-            "type": "string"
-          },
-          "value": {
-            "type": "object",
-            "description": "a JSON Schema"
-          }
-        }
+        "$ref": "#/$defs/state"
       }
     },
     "provisions": {
@@ -377,7 +361,7 @@
           },
           "of": {
             "type": "string",
-            "pattern": "^(verb:[a-z][a-z0-9-]*\\.(input|answer)|accept:[a-z][a-z0-9-]*|event:[a-z][a-z0-9-]*|holder-event:[a-z][a-z0-9-]*(\\.[a-z][a-z0-9-]*)*)$"
+            "pattern": "^(verb:[a-z][a-z0-9-]*\\.(input|answer)|accept:[a-z][a-z0-9-]*|event:[a-z][a-z0-9-]*|state:[a-z][a-z0-9-]*/.+|holder-event:[a-z][a-z0-9-]*(\\.[a-z][a-z0-9-]*)*)$"
           },
           "subject": {
             "type": "string"
@@ -410,6 +394,81 @@
           "uniqueItems": true
         }
       }
+    },
+    "state": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": [
+        "name",
+        "template",
+        "key-forms"
+      ],
+      "properties": {
+        "name": {
+          "type": "string",
+          "pattern": "^[a-z][a-z0-9-]*$"
+        },
+        "template": {
+          "enum": [
+            "state",
+            "events",
+            "work-queue",
+            "log",
+            "objects",
+            "ledger"
+          ],
+          "description": "ADR 0595 \u00a72"
+        },
+        "writer": {
+          "enum": [
+            "holder",
+            "caller"
+          ],
+          "description": "holder when not given; caller when the seat's callers write their own keys"
+        },
+        "key-forms": {
+          "type": "array",
+          "minItems": 1,
+          "items": {
+            "$ref": "#/$defs/keyForm"
+          }
+        },
+        "history": {
+          "type": "integer",
+          "minimum": 0,
+          "description": "past values a key keeps; the state template only"
+        },
+        "max-age-days": {
+          "type": "integer",
+          "minimum": 0,
+          "description": "days a message is kept; the events, work-queue and log templates only"
+        },
+        "description": {
+          "type": "string"
+        }
+      }
+    },
+    "keyForm": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": [
+        "key",
+        "value"
+      ],
+      "properties": {
+        "key": {
+          "type": "string",
+          "minLength": 1,
+          "description": "a pattern of named parts between angle brackets, the rest literal: <asker>.<id>"
+        },
+        "value": {
+          "type": "object",
+          "description": "a JSON Schema"
+        },
+        "description": {
+          "type": "string"
+        }
+      }
     }
   }
 }
diff --git a/seats/operator-channel/seat.json b/seats/operator-channel/seat.json
index 4fe0a0c..9770349 100644
--- a/seats/operator-channel/seat.json
+++ b/seats/operator-channel/seat.json
@@ -172,14 +172,21 @@
     "name": "operator-channel.decided",
     "max-age-days": 7
   },
-  "records": [
+  "states": [
     {
       "name": "asks",
-      "key": "<asker>.<id>",
-      "value": {
-        "type": "object",
-        "description": "one ask the router holds and how it stands"
-      }
+      "template": "state",
+      "key-forms": [
+        {
+          "key": "<asker>.<id>",
+          "value": {
+            "type": "object",
+            "description": "one ask the router holds and how it stands"
+          },
+          "description": "one ask the router holds and how it stands"
+        }
+      ],
+      "description": "the asks a module raised and the router holds, one key per asker and ask"
     }
   ],
   "holder-events": [