SPEC v1.1 : une décroissance montrée nomme sa lecture

Un auditeur qui voit une confiance décrue ne peut pas la reproduire s'il
ignore quelle fonction l'a produite, dans quelle version, à quelle date.
Deux lectures divergentes du même verbatim se valent alors, sans qu'on
puisse dire pourquoi : c'est l'opposabilité qui se fissure, non le fait.

Champ 15 confidence_reading (§4.1), OPTIONNEL — présent seulement quand
l'émetteur EXPOSE une valeur qu'il a dérivée ; ses quatre clés sont alors
requises (policy, version, value, as_of). Le verbatim reste intact au
champ 8. Règle de conformité au §9 : une valeur dérivée non déclarée
n'est pas conforme. Additif et ignorable — un consommateur v1.0 le
préserve et passe, comme §8 l'exige de tout champ inconnu.

Relevé par une lecture extérieure du 2026-09-19 : « c'est une ligne du
contrat, pas une ADR ». Elle avait raison sur les deux points.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

envelope/schema/assertion.schema.json

@@ -1,8 +1,8 @@
 {
   "$schema": "https://json-schema.org/draft/2020-12/schema",
   "$id": "https://prismagram.com/published-language/envelope/1.0/assertion.schema.json",
-  "title": "Assertion Envelope v0.1",
-  "description": "Producer contract for envelope v0.1 messages (SPEC.md §4). One cross-field rule cannot be expressed here and is enforced by the conformance runner: `jurisdiction` MUST equal the prefix of `id`.",
+  "title": "Assertion Envelope v1.1",
+  "description": "Producer contract for envelope v1.1 messages (SPEC.md §4). One cross-field rule cannot be expressed here and is enforced by the conformance runner: `jurisdiction` MUST equal the prefix of `id`.",
   "type": "object",
   "required": [
     "envelope",
@@ -25,9 +25,10 @@
     "envelope": {
       "enum": [
         "0.1",
-        "1.0"
+        "1.0",
+        "1.1"
       ],
-      "description": "Version of the contract. v1.0 is substantively identical to v0.1 (SPEC §8): both values validate. A message that does not declare its version is not versioned (A1 §3)."
+      "description": "Version of the contract. v1.0 is substantively identical to v0.1 (SPEC §8): both values validate. v1.1 adds the optional declared reading (§4.1). A message that does not declare its version is not versioned (A1 §3)."
     },
     "id": {
       "type": "string",
@@ -178,6 +179,40 @@
           "minLength": 1
         }
       ]
+    },
+    "confidence_reading": {
+      "type": "object",
+      "description": "OPTIONAL (SPEC §4.1, v1.1). Present only when the sender exposes a value it derived from `confidence`. A derived value shown without this object is not conformant: nobody could reproduce it.",
+      "required": [
+        "policy",
+        "version",
+        "value",
+        "as_of"
+      ],
+      "additionalProperties": false,
+      "properties": {
+        "policy": {
+          "type": "string",
+          "minLength": 1,
+          "description": "Name of the reading applied — not the value it produced."
+        },
+        "version": {
+          "type": "string",
+          "minLength": 1,
+          "description": "Version of that reading. Two auditors on two dates must be able to tell whether they read alike."
+        },
+        "value": {
+          "type": "number",
+          "minimum": 0,
+          "maximum": 1,
+          "description": "The derived value. The verbatim one stays in `confidence`, untouched."
+        },
+        "as_of": {
+          "type": "string",
+          "format": "date-time",
+          "description": "When the reading was taken. A decay without a date is not reproducible."
+        }
+      }
     }
   },
   "patternProperties": {