diff --git a/docs/api/openapi.yaml b/docs/api/openapi.yaml
index 22eb9ba0b..c6ff8a5ec 100644
--- a/docs/api/openapi.yaml
+++ b/docs/api/openapi.yaml
@@ -5961,21 +5961,23 @@ paths:
         - in: query
           name: from
           schema:
-            description: Window start (inclusive). Defaults to 90 days before `to`; clamped to the medication's `createdAt` and a
-              366-day span floor.
+            description: Window start (inclusive). Defaults to 90 days before `to`; clamped to a 366-day span floor. Recorded doses
+              are returned from this instant; expected slots are not minted before the medication's `createdAt`.
             type: string
             format: date-time
             pattern: ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z|([+-](?:[01]\d|2[0-3]):[0-5]\d)))$
-          description: Window start (inclusive). Defaults to 90 days before `to`; clamped to the medication's `createdAt` and a
-            366-day span floor.
+          description: Window start (inclusive). Defaults to 90 days before `to`; clamped to a 366-day span floor. Recorded doses
+            are returned from this instant; expected slots are not minted before the medication's `createdAt`.
         - in: query
           name: to
           schema:
-            description: Window end (inclusive). Defaults to now. Must be ≥ `from`.
+            description: Window end (inclusive). Defaults to now. Must be ≥ `from`. A dose recorded ahead of its slot (the slot's
+              time within a day after `to`) is still returned.
             type: string
             format: date-time
             pattern: ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z|([+-](?:[01]\d|2[0-3]):[0-5]\d)))$
-          description: Window end (inclusive). Defaults to now. Must be ≥ `from`.
+          description: Window end (inclusive). Defaults to now. Must be ≥ `from`. A dose recorded ahead of its slot (the slot's
+            time within a day after `to`) is still returned.
       responses:
         "200":
           description: Dose-history ledger.
@@ -43671,10 +43673,13 @@ components:
           type: string
           format: date-time
           pattern: ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z|([+-](?:[01]\d|2[0-3]):[0-5]\d)))$
+          description: "Start of the window recorded doses were read over: the requested `from` after the span clamp."
         to:
           type: string
           format: date-time
           pattern: ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z|([+-](?:[01]\d|2[0-3]):[0-5]\d)))$
+          description: "End of the window recorded doses were read over: the requested `to`, or the slot time of a dose recorded
+            ahead of its slot when that lies later (at most one day after `to`)."
         family:
           type: string
           enum:
diff --git a/src/app/api/medications/[id]/dose-history/__tests__/route.test.ts b/src/app/api/medications/[id]/dose-history/__tests__/route.test.ts
index 23e01838e..1cccc72ad 100644
--- a/src/app/api/medications/[id]/dose-history/__tests__/route.test.ts
+++ b/src/app/api/medications/[id]/dose-history/__tests__/route.test.ts
@@ -344,6 +344,9 @@ describe("GET /api/medications/[id]/dose-history — intakes recorded before cre
           json.data.rows as Array<{ intake: { id: string | null } | null }>
         ).map((r) => r.intake?.id);
         expect(ids).toContain("evt-earlier-today");
+        // The response reports the window the recorded doses were read
+        // over: the requested start, not the medication's creation.
+        expect(json.data.from).toBe(from);
       } finally {
         vi.useRealTimers();
       }
@@ -410,6 +413,9 @@ describe("GET /api/medications/[id]/dose-history — early take (#1028 class)",
         status: string;
         intake: { id: string | null } | null;
       }>;
+      // `to` reports how far recorded doses were read: up to the early
+      // dose's slot, past the request's own now.
+      expect(json.data.to).toBe(slot.toISOString());
       const early = rows.find((r) => r.intake?.id === "evt-early");
       expect(early?.status).toBe("taken_on_time");
       // The read horizon stretches only to the recorded anchor: no later
diff --git a/src/app/api/medications/[id]/dose-history/route.ts b/src/app/api/medications/[id]/dose-history/route.ts
index 11256b61f..8b1dae088 100644
--- a/src/app/api/medications/[id]/dose-history/route.ts
+++ b/src/app/api/medications/[id]/dose-history/route.ts
@@ -313,9 +313,13 @@ export const GET = apiHandler(
       meta: { row_count: serialized.length, family },
     });
 
+    // The window the recorded doses were read over (#1028): from the
+    // requested start (slots additionally start at the medication's
+    // creation) to the read horizon, which reaches past `to` only for a dose
+    // recorded ahead of its slot.
     return apiSuccess({
-      from: from.toISOString(),
-      to: to.toISOString(),
+      from: intakeFrom.toISOString(),
+      to: horizon.toISOString(),
       family,
       hasExpectedSlots: bands.length > 0,
       rows: serialized,
diff --git a/src/lib/openapi/routes/medications/schemas.ts b/src/lib/openapi/routes/medications/schemas.ts
index 02b1a3908..47a2bd6e3 100644
--- a/src/lib/openapi/routes/medications/schemas.ts
+++ b/src/lib/openapi/routes/medications/schemas.ts
@@ -911,12 +911,14 @@ export const doseHistoryQuery = z.object({
     .datetime({ offset: true })
     .optional()
     .describe(
-      "Window start (inclusive). Defaults to 90 days before `to`; clamped to the medication's `createdAt` and a 366-day span floor.",
+      "Window start (inclusive). Defaults to 90 days before `to`; clamped to a 366-day span floor. Recorded doses are returned from this instant; expected slots are not minted before the medication's `createdAt`.",
     ),
   to: z.iso
     .datetime({ offset: true })
     .optional()
-    .describe("Window end (inclusive). Defaults to now. Must be ≥ `from`."),
+    .describe(
+      "Window end (inclusive). Defaults to now. Must be ≥ `from`. A dose recorded ahead of its slot (the slot's time within a day after `to`) is still returned.",
+    ),
 });
 
 const doseHistoryRow = z
@@ -982,8 +984,16 @@ const doseHistoryRow = z
 
 export const doseHistoryResponse = z
   .object({
-    from: z.iso.datetime({ offset: true }),
-    to: z.iso.datetime({ offset: true }),
+    from: z.iso
+      .datetime({ offset: true })
+      .describe(
+        "Start of the window recorded doses were read over: the requested `from` after the span clamp.",
+      ),
+    to: z.iso
+      .datetime({ offset: true })
+      .describe(
+        "End of the window recorded doses were read over: the requested `to`, or the slot time of a dose recorded ahead of its slot when that lies later (at most one day after `to`).",
+      ),
     family: z
       .enum(["daily", "weekly", "one_shot", "none"])
       .describe("Cadence family the window's slots were minted under."),