fix(checkpoint): stop reread loops for complete writebacks

docs/reference/protocols/goal-vision-replan-contract-v0.md

@@ -1086,6 +1086,12 @@ in its durable-writeback step, the replan contract uses a same-response
 Different schemas remain separate, and progress-only replan does not acquire a
 Vision requirement. TurnEnvelope preserves the ordinary plan's guidance.
 
+`checkpoint_context_not_missing` is an inapplicable recovery, not a request to
+repeat that read. Its `reread_required` is false. Preserve the committed writeback
+and quota receipt; inspect later authorized work through the normal guard with
+a fresh Turn identity. A stale, missing or replaced read receipt still requires
+the original scoped reread. Neither rejection grants execution or completion.
+
 Shared `todo plan` and guided-start authoring steps also provide a routed exact
 readback command for each authored or reused Todo id. Inventory text is a bounded
 excerpt. Verify `todo_detail_projection.source_complete=true`, compare `.todo.text`
@@ -1103,6 +1109,11 @@ Turn 写回后的恢复。规划与接续指引提供逐条精确读回命令，
 需求和当前状态，不能拿列表摘要判断正文丢失。读取不授予执行权限；准入、租约、
 恢复和单次记账规则保持不变。包体增量与模型效率、效果收益须分别测量。
 
+`checkpoint_context_not_missing` 表示这条恢复路径不适用，`reread_required=false`，
+不应重复同一读取。保留已提交写回与记账回执；后续获授权的工作通过正常 guard 和新
+Turn 身份检查。陈旧、缺失或被替换的读取回执仍须按原范围重读。拒绝不授予执行或
+完成权限。
+
 A satisfied checkpoint is protocol-complete, but a material closeout also has
 to qualify its relationship to the final outcome. A patched checkpoint must
 name the active `acceptance_summary`, attach public-safe

loopx/control_plane/goals/checkpoint_read_context.ts

@@ -77,8 +77,13 @@ function snapshot(request: JsonObject): JsonObject {
 }
 
 const rejected = (code: string, changed: string[] = []): JsonObject => ({
-  ok: false, error_code: code, reread_required: true, changed_components: changed,
-  error: `${code}: run checkpoint-context for the same Goal/Agent/Todo or obligation/Turn, ` +
+  ok: false, error_code: code, reread_required: code !== "checkpoint_context_not_missing", changed_components: changed,
+  error: code === "checkpoint_context_not_missing"
+    ? `${code}: this committed writeback has no missing checkpoint for this recovery. ` +
+      "Preserve the committed writeback and quota receipt; do not repeat this recovery or quota spend. " +
+      "For later authorized work, inspect current state through the normal guard with a fresh Turn identity. " +
+      "This rejection grants no work or completion authority."
+    : `${code}: run checkpoint-context for the same Goal/Agent/Todo or obligation/Turn, ` +
     "read the returned state and judge again; submit its --checkpoint-read-context with only the vision decision. " +
     "Do not repeat implementation, state mutations, or quota spend.",
 });

tests/control_plane/test_checkpoint_read_context.py

@@ -84,6 +84,11 @@ def test_missing_replaced_stale_context_requires_reread_and_preserves_delivery(t
     assert rc == 0 and result["appended"] and result["vision_checkpoint"]["satisfied"], result
     assert result["vision_checkpoint"]["read_context"]["read_context_id"] == fresh["read_context_id"]
     after = index.read_bytes()
+    rc, inapplicable = _run_cli(registry, runtime, "checkpoint-context", *binding, cwd=project)
+    assert rc == 1 and inapplicable["error_code"] == "checkpoint_context_not_missing", inapplicable
+    assert inapplicable["checkpoint_read_context"]["reread_required"] is False
+    assert "normal guard" in inapplicable["error"]
+    assert index.read_bytes() == after, "an inapplicable recovery must not append another receipt"
     state.write_text(state.read_text(encoding="utf-8") + "\n## Acceptance\n\nNew acceptance after commit.\n", encoding="utf-8")
     rc, replay = _run_cli(registry, runtime, *supplement, cwd=project)
     assert rc == 0 and replay["idempotent_replay"] and not replay["appended"], replay

tests/control_plane_ts/checkpoint_read_context.test.ts

@@ -31,6 +31,19 @@ test("read captures the exact task, transitive upstream results and goal accepta
   assert.equal(check(result.receipt).ok, true);
 });
 
+test("an inapplicable recovery does not direct the caller to repeat the same read", () => {
+  const result = read({prior: {vision_checkpoint: {
+    decision: "unchanged_with_reason", satisfied: true, delivery_boundary: "in_flight_continuation",
+  }}, writeback_committed: true, quota_spend_committed: true});
+  assert.equal(result.ok, false);
+  assert.equal(result.error_code, "checkpoint_context_not_missing");
+  assert.equal(result.reread_required, false);
+  assert.doesNotMatch(String(result.error), /run checkpoint-context/);
+  assert.match(String(result.error), /normal guard/);
+  const missing = check(undefined);
+  assert.equal(missing.reread_required, true, "a genuinely missing receipt still requires reread");
+});
+
 test("an unqualified blocked replan needs the exact committed source and no debit before reread", () => {
   const bound = settlementIdentity({goal_id: "goal", agent_id: "agent", turn_instance_id: "turn",
     replan_obligation_id: "replan-1111111111111111"});