diff --git a/__tests__/space-reputation-serialization.test.ts b/__tests__/space-reputation-serialization.test.ts
new file mode 100644
index 0000000..d9c0cb0
--- /dev/null
+++ b/__tests__/space-reputation-serialization.test.ts
@@ -0,0 +1,133 @@
+import axios from "axios";
+
+import { searchContent } from "../src/modules/search";
+import { fetchManyEntities, fetchEntity } from "../src/modules/entities";
+import { fetchUserByForeignId } from "../src/modules/users";
+import { buildSpaceReputationParams } from "../src/core/spaceReputationParams";
+import { makeClient, MockAxiosInstance } from "./helpers/mockClient";
+
+/**
+ * THE serialization regression guard for the `spaceReputation` object (Task 3.4).
+ *
+ * The central risk: if the nested `spaceReputation` object is forwarded to axios
+ * `params` un-normalized, axios bracket-encodes it
+ * (`spaceReputation%5BspaceId%5D=…`) and the server IGNORES it — so the new
+ * (primary) form silently no-ops while the deprecated flat props keep working.
+ * Typecheck and the existing flat-prop tests both stay green when that happens.
+ *
+ * These tests pass the OBJECT form, capture the exact `params` object handed to
+ * the mocked axios instance, serialize it through axios's OWN default param
+ * serializer (`getUri`), and assert the resulting query string is the FLAT
+ * `spaceReputationId=…&spaceReputationDescendants=…` — never dropped, never
+ * bracketed. Each forwarding shape present in the modules is covered:
+ *   - silent-drop (explicit `params: { spaceReputationId, ... }`)   → searchContent
+ *   - silent-drop (explicit field-assign params object)            → fetchUserByForeignId
+ *   - `params: data` bracket-leak                                  → fetchManyEntities
+ *   - rest-spread `const { id, ...params } = data` bracket-leak    → fetchEntity
+ */
+
+// A real axios instance used purely as an oracle for default param
+// serialization — the same algorithm the SDK's live instances use.
+const serializer = axios.create();
+
+/** Serialize a captured `params` object exactly as axios would put it on the wire. */
+function serializeParams(params: unknown): string {
+  const uri = serializer.getUri({ url: "/x", params: params as any });
+  const qIndex = uri.indexOf("?");
+  return qIndex === -1 ? "" : uri.slice(qIndex + 1);
+}
+
+/** Pull the `params` object out of the most recent axios get/post mock call. */
+function capturedParams(method: jest.Mock): unknown {
+  const call = method.mock.calls[method.mock.calls.length - 1];
+  // get(path, config) → config is arg 1; post(path, body, config) → config is arg 2.
+  const config = call.length >= 3 ? call[2] : call[1];
+  return (config as { params?: unknown })?.params;
+}
+
+function assertFlatRepQuery(method: jest.Mock) {
+  const params = capturedParams(method) as Record<string, unknown>;
+
+  // The object must never reach axios params un-normalized.
+  expect(params).not.toHaveProperty("spaceReputation");
+  // It must be flattened (not dropped).
+  expect(params.spaceReputationId).toBe("rep1");
+  expect(params.spaceReputationDescendants).toBe(true);
+
+  // And the serialized wire string must be flat, never bracketed.
+  const query = serializeParams(params);
+  expect(query).toContain("spaceReputationId=rep1");
+  expect(query).toContain("spaceReputationDescendants=true");
+  expect(query).not.toContain("spaceReputation%5B"); // spaceReputation[
+  expect(query).not.toContain("spaceReputation["); // un-encoded, just in case
+}
+
+describe("space-reputation serialization guard — object form never drops or brackets", () => {
+  it("silent-drop shape (explicit params object): searchContent", async () => {
+    const { client, projectInstance } = makeClient();
+    await searchContent(client, {
+      query: "hello",
+      spaceReputation: { spaceId: "rep1", includeDescendants: true },
+    });
+    assertFlatRepQuery(projectInstance.post as unknown as jest.Mock);
+  });
+
+  it("silent-drop shape (explicit field-assign): fetchUserByForeignId", async () => {
+    const { client, projectInstance } = makeClient();
+    await fetchUserByForeignId(client, {
+      foreignId: "fid-1",
+      spaceReputation: { spaceId: "rep1", includeDescendants: true },
+    });
+    assertFlatRepQuery(projectInstance.get as unknown as jest.Mock);
+  });
+
+  it("`params: data` bracket-leak shape: fetchManyEntities", async () => {
+    const { client, projectInstance } = makeClient();
+    await fetchManyEntities(client, {
+      sortBy: "hot",
+      spaceReputation: { spaceId: "rep1", includeDescendants: true },
+    });
+    assertFlatRepQuery(projectInstance.get as unknown as jest.Mock);
+    // The unrelated param still rides along.
+    const params = capturedParams(projectInstance.get as unknown as jest.Mock) as Record<
+      string,
+      unknown
+    >;
+    expect(params.sortBy).toBe("hot");
+  });
+
+  it("rest-spread bracket-leak shape: fetchEntity", async () => {
+    const { client, projectInstance } = makeClient();
+    await fetchEntity(client, {
+      entityId: "e1",
+      include: "author",
+      spaceReputation: { spaceId: "rep1", includeDescendants: true },
+    });
+    assertFlatRepQuery(projectInstance.get as unknown as jest.Mock);
+    const params = capturedParams(projectInstance.get as unknown as jest.Mock) as Record<
+      string,
+      unknown
+    >;
+    expect(params.include).toBe("author");
+    expect(params).not.toHaveProperty("entityId"); // path param, not a query param
+  });
+
+  it("object form wins over deprecated flat props (precedence)", () => {
+    const out = buildSpaceReputationParams({
+      spaceReputation: { spaceId: "rep1", includeDescendants: true },
+      spaceReputationId: "ignored",
+      spaceReputationDescendants: false,
+    });
+    expect(out).toEqual({
+      spaceReputationId: "rep1",
+      spaceReputationDescendants: true,
+    });
+  });
+
+  it("`spaceId: \"none\"` flattens to `spaceReputationId=none` without descendants", () => {
+    const out = buildSpaceReputationParams({
+      spaceReputation: { spaceId: "none" },
+    });
+    expect(out).toEqual({ spaceReputationId: "none" });
+  });
+});
diff --git a/src/core/spaceReputationParams.ts b/src/core/spaceReputationParams.ts
new file mode 100644
index 0000000..fa4e8c5
--- /dev/null
+++ b/src/core/spaceReputationParams.ts
@@ -0,0 +1,123 @@
+/**
+ * Input accepted by {@link buildSpaceReputationParams}: either the new
+ * `spaceReputation` object or the deprecated flat props.
+ *
+ * The flat inputs accept `null` (in addition to `undefined`) so the helper's
+ * contract matches `@sublay/core` exactly; `null` is treated as unset. node-sdk
+ * never persists these params, so the `null` tolerance is not strictly required
+ * here, but matching core is harmless and consistent.
+ */
+export interface BuildSpaceReputationParamsInput {
+  spaceReputation?: {
+    spaceId: string | "none" | "context";
+    includeDescendants?: boolean;
+  };
+  /**
+   * @deprecated Pass `spaceReputation` instead. Accepted for back-compat.
+   */
+  spaceReputationId?: string | null;
+  /**
+   * @deprecated Pass `spaceReputation` instead. Accepted for back-compat.
+   */
+  spaceReputationDescendants?: boolean | null;
+}
+
+/**
+ * Flat output handed to the query-string serializer (axios `params`). Both keys
+ * are omitted when unset — never bracketed, never nested.
+ */
+export interface SpaceReputationFlatParams {
+  spaceReputationId?: string;
+  spaceReputationDescendants?: boolean;
+}
+
+// Ambient `process` declaration so this file typechecks under the publish build
+// tsconfig (which does not pull in @types/node). At runtime node-sdk always runs
+// under Node, so `process.env` is present; the `typeof` guard keeps it safe
+// anywhere it isn't.
+declare const process:
+  | { env?: Record<string, string | undefined> }
+  | undefined;
+
+let bothFormsWarned = false;
+
+function isProduction(): boolean {
+  return (
+    typeof process !== "undefined" &&
+    !!process.env &&
+    process.env.NODE_ENV === "production"
+  );
+}
+
+/**
+ * Normalize the `spaceReputation` object or the deprecated flat props down to
+ * the flat query params the server understands
+ * (`spaceReputationId` / `spaceReputationDescendants`).
+ *
+ * **Critical:** this is the only thing that prevents the nested
+ * `spaceReputation` object from reaching axios `params`, where axios would
+ * bracket-encode it (`spaceReputation[spaceId]=…`) and the server would ignore
+ * it — silently no-opping the new (primary) form. Every reputation-consuming
+ * module must route the object through here and merge only the flat output.
+ *
+ * Rules (mirrors the `@sublay/core` helper contract):
+ * - **Object wins when present.** "Present" means the `spaceReputation` key was
+ *   supplied at all (`spaceReputation !== undefined`) — even `{}` or a partial
+ *   object suppresses the flat props.
+ * - When **both** the object and a flat prop are supplied, the object wins and a
+ *   one-time dev-only `console.warn` fires (never throws).
+ * - The flat inputs tolerate `null` (treated as unset → param omitted).
+ * - Output keys are omitted when unset; the result is always the two flat keys,
+ *   never a bracketed/nested object.
+ */
+export function buildSpaceReputationParams(
+  input: BuildSpaceReputationParamsInput
+): SpaceReputationFlatParams {
+  const { spaceReputation, spaceReputationId, spaceReputationDescendants } =
+    input;
+
+  const objectPresent = spaceReputation !== undefined;
+  const flatPresent =
+    (spaceReputationId !== undefined && spaceReputationId !== null) ||
+    (spaceReputationDescendants !== undefined &&
+      spaceReputationDescendants !== null);
+
+  if (objectPresent && flatPresent && !bothFormsWarned && !isProduction()) {
+    bothFormsWarned = true;
+    // eslint-disable-next-line no-console
+    console.warn(
+      "[Sublay] Both `spaceReputation` and the deprecated flat props " +
+        "(`spaceReputationId` / `spaceReputationDescendants`) were supplied. " +
+        "The `spaceReputation` object takes precedence; the flat props are ignored. " +
+        "Remove the flat props — they are deprecated."
+    );
+  }
+
+  const result: SpaceReputationFlatParams = {};
+
+  if (objectPresent) {
+    // Object form chosen. Read from the object; ignore the flat props entirely.
+    const spaceId = spaceReputation!.spaceId;
+    if (spaceId !== undefined && spaceId !== null) {
+      result.spaceReputationId = spaceId;
+    }
+    const includeDescendants = spaceReputation!.includeDescendants;
+    if (includeDescendants !== undefined && includeDescendants !== null) {
+      result.spaceReputationDescendants = includeDescendants;
+    }
+    return result;
+  }
+
+  // Flat form. `null` is treated as unset (param omitted).
+  if (spaceReputationId !== undefined && spaceReputationId !== null) {
+    result.spaceReputationId = spaceReputationId;
+  }
+  if (
+    spaceReputationDescendants !== undefined &&
+    spaceReputationDescendants !== null
+  ) {
+    result.spaceReputationDescendants = spaceReputationDescendants;
+  }
+
+  return result;
+}
diff --git a/src/interfaces/SpaceReputation.ts b/src/interfaces/SpaceReputation.ts
index 77d2eba..db3bc1c 100644
--- a/src/interfaces/SpaceReputation.ts
+++ b/src/interfaces/SpaceReputation.ts
@@ -12,7 +12,15 @@
  *   module). Accept `<uuid> | "none"` only; `"context"` is rejected (400).
  *
  * Both classes share the same param names and types — only the accepted
- * `spaceReputationId` value set (documented in JSDoc) differs.
+ * `spaceId` value set (documented in JSDoc) differs.
+ *
+ * **Preferred form:** pass the `spaceReputation` object (`{ spaceId,
+ * includeDescendants? }`). The flat props (`spaceReputationId` /
+ * `spaceReputationDescendants`) are `@deprecated` but still accepted; when both
+ * forms are supplied the object wins. The object is normalized to the flat wire
+ * params by `buildSpaceReputationParams` before it reaches the request — it must
+ * never be forwarded to axios `params` un-normalized (axios would bracket-encode
+ * it and the server would ignore it).
  */
 
 /**
@@ -22,6 +30,21 @@
  */
 export interface SpaceReputationContextParams {
   /**
+   * Opt the returned/embedded user(s) into a space-scoped `spaceReputation`.
+   * Accepted `spaceId` forms:
+   * - a space `<uuid>` — reputation scoped to that specific space
+   * - `"none"` — the user's global, non-space reputation
+   * - `"context"` — reputation scoped to each row's own space (per-row)
+   *
+   * `includeDescendants` includes reputation accrued in descendant spaces; only
+   * honored when `spaceId` is an explicit `<uuid>`.
+   */
+  spaceReputation?: {
+    spaceId: string | "none" | "context";
+    includeDescendants?: boolean;
+  };
+  /**
+   * @deprecated Pass `spaceReputation` instead. Retained for back-compat.
    * Opt the returned/embedded user(s) into a space-scoped `spaceReputation`.
    * Accepted forms:
    * - a space `<uuid>` — reputation scoped to that specific space
@@ -30,8 +53,9 @@ export interface SpaceReputationContextParams {
    */
   spaceReputationId?: string;
   /**
-   * Include reputation accrued in descendant spaces. Only honored when
-   * `spaceReputationId` is an explicit `<uuid>`; ignored for `"none"` and
+   * @deprecated Pass `spaceReputation.includeDescendants` instead. Retained for
+   * back-compat. Include reputation accrued in descendant spaces. Only honored
+   * when `spaceReputationId` is an explicit `<uuid>`; ignored for `"none"` and
    * disallowed (not applicable) with `"context"`.
    */
   spaceReputationDescendants?: boolean;
@@ -46,17 +70,32 @@ export interface SpaceReputationContextParams {
 export interface SpaceReputationUserParams {
   /**
    * Opt the returned user(s) into a space-scoped `spaceReputation`.
-   * Accepted forms:
+   * Accepted `spaceId` forms:
    * - a space `<uuid>` — reputation scoped to that specific space
    * - `"none"` — the user's global, non-space reputation
    *
    * Note: `"context"` is rejected by the server (400) on user-direct routes;
    * pass an explicit `<uuid>` or `"none"` here.
+   *
+   * `includeDescendants` includes reputation accrued in descendant spaces; only
+   * honored when `spaceId` is an explicit `<uuid>`.
+   */
+  spaceReputation?: {
+    spaceId: string | "none";
+    includeDescendants?: boolean;
+  };
+  /**
+   * @deprecated Pass `spaceReputation` instead. Retained for back-compat.
+   * Opt the returned user(s) into a space-scoped `spaceReputation`.
+   * Accepted forms:
+   * - a space `<uuid>` — reputation scoped to that specific space
+   * - `"none"` — the user's global, non-space reputation
    */
   spaceReputationId?: string;
   /**
-   * Include reputation accrued in descendant spaces. Only honored when
-   * `spaceReputationId` is an explicit `<uuid>`; ignored for `"none"`.
+   * @deprecated Pass `spaceReputation.includeDescendants` instead. Retained for
+   * back-compat. Include reputation accrued in descendant spaces. Only honored
+   * when `spaceReputationId` is an explicit `<uuid>`; ignored for `"none"`.
    */
   spaceReputationDescendants?: boolean;
 }
diff --git a/src/modules/chat/getMessage.ts b/src/modules/chat/getMessage.ts
index c660603..99f6228 100644
--- a/src/modules/chat/getMessage.ts
+++ b/src/modules/chat/getMessage.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { ChatMessage } from "../../interfaces/ChatMessage";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface GetMessageProps extends SpaceReputationContextParams {
   conversationId: string;
@@ -13,10 +14,26 @@ export async function getMessage(
   client: SublayHttpClient,
   data: GetMessageProps
 ): Promise<ChatMessage> {
-  const { conversationId, messageId, ...params } = data;
+  const {
+    conversationId,
+    messageId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<ChatMessage>(
     `/chat/conversations/${conversationId}/messages/${messageId}`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/chat/listMembers.ts b/src/modules/chat/listMembers.ts
index 0c38180..13f06af 100644
--- a/src/modules/chat/listMembers.ts
+++ b/src/modules/chat/listMembers.ts
@@ -2,6 +2,7 @@ import { SublayHttpClient } from "../../core/client";
 import { ConversationMember } from "../../interfaces/ConversationMember";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface ListMembersProps extends SpaceReputationContextParams {
   conversationId: string;
@@ -16,9 +17,24 @@ export async function listMembers(
   client: SublayHttpClient,
   data: ListMembersProps
 ): Promise<PaginatedResponse<ConversationMember>> {
-  const { conversationId, ...params } = data;
+  const {
+    conversationId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<
     PaginatedResponse<ConversationMember>
-  >(`/chat/conversations/${conversationId}/members`, { params });
+  >(`/chat/conversations/${conversationId}/members`, {
+    params: {
+      ...rest,
+      ...buildSpaceReputationParams({
+        spaceReputation,
+        spaceReputationId,
+        spaceReputationDescendants,
+      }),
+    },
+  });
   return response.data;
 }
diff --git a/src/modules/chat/listMessages.ts b/src/modules/chat/listMessages.ts
index a4051ff..98149f3 100644
--- a/src/modules/chat/listMessages.ts
+++ b/src/modules/chat/listMessages.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { ChatMessage } from "../../interfaces/ChatMessage";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface MessageFilters {
   /**
@@ -46,10 +47,25 @@ export async function listMessages(
   client: SublayHttpClient,
   data: ListMessagesProps
 ): Promise<ListMessagesResponse> {
-  const { conversationId, ...params } = data;
+  const {
+    conversationId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<ListMessagesResponse>(
     `/chat/conversations/${conversationId}/messages`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/chat/listReactions.ts b/src/modules/chat/listReactions.ts
index 818ba68..c7b6e21 100644
--- a/src/modules/chat/listReactions.ts
+++ b/src/modules/chat/listReactions.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { User } from "../../interfaces/User";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 import { PaginationMetadata } from "../../interfaces/IPaginatedResponse";
 
 export interface ListReactionsProps extends SpaceReputationContextParams {
@@ -29,10 +30,26 @@ export async function listReactions(
   client: SublayHttpClient,
   data: ListReactionsProps
 ): Promise<ListReactionsResponse> {
-  const { conversationId, messageId, ...params } = data;
+  const {
+    conversationId,
+    messageId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<ListReactionsResponse>(
     `/chat/conversations/${conversationId}/messages/${messageId}/reactions`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/chat/sendMessage.ts b/src/modules/chat/sendMessage.ts
index 1ac915c..59b04cc 100644
--- a/src/modules/chat/sendMessage.ts
+++ b/src/modules/chat/sendMessage.ts
@@ -4,6 +4,7 @@ import { ChatMessage } from "../../interfaces/ChatMessage";
 import { GifData } from "../../interfaces/Comment";
 import { Mention } from "../../interfaces/Mention";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface ChatMessageFile {
   file: Uint8Array | Blob;
@@ -34,6 +35,7 @@ export async function sendMessage(
   const {
     conversationId,
     files,
+    spaceReputation,
     spaceReputationId,
     spaceReputationDescendants,
     ...body
@@ -42,7 +44,11 @@ export async function sendMessage(
 
   // Space-reputation opts go as query params (never body fields), so they
   // travel the same way for both the JSON and multipart variants.
-  const params = { spaceReputationId, spaceReputationDescendants };
+  const params = buildSpaceReputationParams({
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+  });
 
   // With attachments, send multipart: object fields are JSON-stringified (the
   // server parses them back) and the files are appended. Otherwise send JSON.
diff --git a/src/modules/comments/fetchComment.ts b/src/modules/comments/fetchComment.ts
index 09a88c5..eb531f5 100644
--- a/src/modules/comments/fetchComment.ts
+++ b/src/modules/comments/fetchComment.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { Comment } from "../../interfaces/Comment";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchCommentProps extends SpaceReputationContextParams {
   commentId: string;
@@ -11,10 +12,25 @@ export async function fetchComment(
   client: SublayHttpClient,
   data: FetchCommentProps
 ): Promise<Comment> {
-  const { commentId, ...params } = data;
+  const {
+    commentId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<Comment>(
     `/comments/${commentId}`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/comments/fetchManyComments.ts b/src/modules/comments/fetchManyComments.ts
index 0e6b117..9a3e82d 100644
--- a/src/modules/comments/fetchManyComments.ts
+++ b/src/modules/comments/fetchManyComments.ts
@@ -2,6 +2,7 @@ import { SublayHttpClient } from "../../core/client";
 import { Comment } from "../../interfaces/Comment";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchManyCommentsProps extends SpaceReputationContextParams {
   entityId?: string;
@@ -31,9 +32,20 @@ export async function fetchManyComments(
   client: SublayHttpClient,
   data: FetchManyCommentsProps
 ): Promise<PaginatedResponse<Comment>> {
+  const { spaceReputation, spaceReputationId, spaceReputationDescendants, ...rest } =
+    data;
   const response = await client.projectInstance.get<PaginatedResponse<Comment>>(
     "/comments",
-    { params: data }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/comments/fetchReactions.ts b/src/modules/comments/fetchReactions.ts
index 75d45c2..10aafa9 100644
--- a/src/modules/comments/fetchReactions.ts
+++ b/src/modules/comments/fetchReactions.ts
@@ -2,6 +2,7 @@ import { SublayHttpClient } from "../../core/client";
 import { Reaction, ReactionType } from "../../interfaces/Reaction";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchCommentReactionsProps
   extends SpaceReputationContextParams {
@@ -16,10 +17,25 @@ export async function fetchReactions(
   client: SublayHttpClient,
   data: FetchCommentReactionsProps
 ): Promise<PaginatedResponse<Reaction>> {
-  const { commentId, ...params } = data;
+  const {
+    commentId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<PaginatedResponse<Reaction>>(
     `/comments/${commentId}/reactions`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/entities/fetchEntity.ts b/src/modules/entities/fetchEntity.ts
index ddafe31..4e51738 100644
--- a/src/modules/entities/fetchEntity.ts
+++ b/src/modules/entities/fetchEntity.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { Entity } from "../../interfaces/Entity";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchEntityProps extends SpaceReputationContextParams {
   entityId: string;
@@ -11,10 +12,25 @@ export async function fetchEntity(
   client: SublayHttpClient,
   data: FetchEntityProps
 ): Promise<Entity> {
-  const { entityId, ...params } = data;
+  const {
+    entityId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<Entity>(
     `/entities/${entityId}`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/entities/fetchManyEntities.ts b/src/modules/entities/fetchManyEntities.ts
index 9e51d58..eb617ef 100644
--- a/src/modules/entities/fetchManyEntities.ts
+++ b/src/modules/entities/fetchManyEntities.ts
@@ -2,6 +2,7 @@ import { SublayHttpClient } from "../../core/client";
 import { Entity } from "../../interfaces/Entity";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface KeywordsFilters {
   includes?: string[];
@@ -99,10 +100,19 @@ export async function fetchManyEntities(
   data: FetchManyEntitiesProps
 ): Promise<PaginatedResponse<Entity>> {
   const path = `/entities`;
+  const { spaceReputation, spaceReputationId, spaceReputationDescendants, ...rest } =
+    data;
   const response = await client.projectInstance.get<PaginatedResponse<Entity>>(
     path,
     {
-      params: data,
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
     }
   );
   return response.data;
diff --git a/src/modules/entities/fetchReactions.ts b/src/modules/entities/fetchReactions.ts
index 0eb3f9c..ecf19d9 100644
--- a/src/modules/entities/fetchReactions.ts
+++ b/src/modules/entities/fetchReactions.ts
@@ -2,6 +2,7 @@ import { SublayHttpClient } from "../../core/client";
 import { Reaction, ReactionType } from "../../interfaces/Reaction";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchEntityReactionsProps extends SpaceReputationContextParams {
   entityId: string;
@@ -15,10 +16,25 @@ export async function fetchReactions(
   client: SublayHttpClient,
   data: FetchEntityReactionsProps
 ): Promise<PaginatedResponse<Reaction>> {
-  const { entityId, ...params } = data;
+  const {
+    entityId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<PaginatedResponse<Reaction>>(
     `/entities/${entityId}/reactions`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/reports/fetchModeratedReports.ts b/src/modules/reports/fetchModeratedReports.ts
index 16a2306..2b5de48 100644
--- a/src/modules/reports/fetchModeratedReports.ts
+++ b/src/modules/reports/fetchModeratedReports.ts
@@ -2,6 +2,7 @@ import { SublayHttpClient } from "../../core/client";
 import { Report, ReportStatus, ReportTargetType } from "../../interfaces/Report";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchModeratedReportsProps
   extends SpaceReputationContextParams {
@@ -18,9 +19,20 @@ export async function fetchModeratedReports(
   client: SublayHttpClient,
   data: FetchModeratedReportsProps
 ): Promise<PaginatedResponse<Report>> {
+  const { spaceReputation, spaceReputationId, spaceReputationDescendants, ...rest } =
+    data;
   const response = await client.projectInstance.get<PaginatedResponse<Report>>(
     "/reports/moderated",
-    { params: data }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/search/askContent.ts b/src/modules/search/askContent.ts
index cdbf41e..39d3601 100644
--- a/src/modules/search/askContent.ts
+++ b/src/modules/search/askContent.ts
@@ -1,5 +1,6 @@
 import { SublayHttpClient } from "../../core/client";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface AskContentProps extends SpaceReputationContextParams {
   query: string;
@@ -24,11 +25,18 @@ export async function askContent(
   client: SublayHttpClient,
   data: AskContentProps
 ): Promise<AskContentResponse> {
-  const { spaceReputationId, spaceReputationDescendants, ...body } = data;
+  const { spaceReputation, spaceReputationId, spaceReputationDescendants, ...body } =
+    data;
   const response = await client.projectInstance.post<AskContentResponse>(
     "/search/ask",
     body,
-    { params: { spaceReputationId, spaceReputationDescendants } }
+    {
+      params: buildSpaceReputationParams({
+        spaceReputation,
+        spaceReputationId,
+        spaceReputationDescendants,
+      }),
+    }
   );
   return response.data;
 }
diff --git a/src/modules/search/searchContent.ts b/src/modules/search/searchContent.ts
index 7ff39fe..9f4cf45 100644
--- a/src/modules/search/searchContent.ts
+++ b/src/modules/search/searchContent.ts
@@ -2,6 +2,7 @@ import { SublayHttpClient } from "../../core/client";
 import { Entity } from "../../interfaces/Entity";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface SearchContentProps extends SpaceReputationContextParams {
   query: string;
@@ -21,11 +22,18 @@ export async function searchContent(
   client: SublayHttpClient,
   data: SearchContentProps
 ): Promise<PaginatedResponse<Entity>> {
-  const { spaceReputationId, spaceReputationDescendants, ...body } = data;
+  const { spaceReputation, spaceReputationId, spaceReputationDescendants, ...body } =
+    data;
   const response = await client.projectInstance.post<PaginatedResponse<Entity>>(
     "/search/content",
     body,
-    { params: { spaceReputationId, spaceReputationDescendants } }
+    {
+      params: buildSpaceReputationParams({
+        spaceReputation,
+        spaceReputationId,
+        spaceReputationDescendants,
+      }),
+    }
   );
   return response.data;
 }
diff --git a/src/modules/spaces/fetchSpaceMembers.ts b/src/modules/spaces/fetchSpaceMembers.ts
index c051758..c778e3e 100644
--- a/src/modules/spaces/fetchSpaceMembers.ts
+++ b/src/modules/spaces/fetchSpaceMembers.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { SpaceMembersResponse } from "../../interfaces/SpaceMember";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchSpaceMembersProps extends SpaceReputationContextParams {
   spaceId: string;
@@ -14,10 +15,25 @@ export async function fetchSpaceMembers(
   client: SublayHttpClient,
   data: FetchSpaceMembersProps
 ): Promise<SpaceMembersResponse> {
-  const { spaceId, ...params } = data;
+  const {
+    spaceId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<SpaceMembersResponse>(
     `/spaces/${spaceId}/members`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/spaces/fetchSpaceTeam.ts b/src/modules/spaces/fetchSpaceTeam.ts
index e07fb99..eaa85db 100644
--- a/src/modules/spaces/fetchSpaceTeam.ts
+++ b/src/modules/spaces/fetchSpaceTeam.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { SpaceTeamResponse } from "../../interfaces/SpaceMember";
 import { SpaceReputationContextParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchSpaceTeamProps extends SpaceReputationContextParams {
   spaceId: string;
@@ -10,10 +11,25 @@ export async function fetchSpaceTeam(
   client: SublayHttpClient,
   data: FetchSpaceTeamProps
 ): Promise<SpaceTeamResponse> {
-  const { spaceId, ...params } = data;
+  const {
+    spaceId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<SpaceTeamResponse>(
     `/spaces/${spaceId}/team`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/users/fetchConnectionsByUserId.ts b/src/modules/users/fetchConnectionsByUserId.ts
index 89c7a2c..0552a2c 100644
--- a/src/modules/users/fetchConnectionsByUserId.ts
+++ b/src/modules/users/fetchConnectionsByUserId.ts
@@ -2,6 +2,7 @@ import { SublayHttpClient } from "../../core/client";
 import { EstablishedConnection } from "../../interfaces/Connection";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 import { SpaceReputationUserParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchConnectionsByUserIdProps
   extends SpaceReputationUserParams {
@@ -14,9 +15,24 @@ export async function fetchConnectionsByUserId(
   client: SublayHttpClient,
   data: FetchConnectionsByUserIdProps
 ): Promise<PaginatedResponse<EstablishedConnection>> {
-  const { userId, ...params } = data;
+  const {
+    userId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<
     PaginatedResponse<EstablishedConnection>
-  >(`/users/${userId}/connections`, { params });
+  >(`/users/${userId}/connections`, {
+    params: {
+      ...rest,
+      ...buildSpaceReputationParams({
+        spaceReputation,
+        spaceReputationId,
+        spaceReputationDescendants,
+      }),
+    },
+  });
   return response.data;
 }
diff --git a/src/modules/users/fetchFollowersByUserId.ts b/src/modules/users/fetchFollowersByUserId.ts
index 14d1216..9e33021 100644
--- a/src/modules/users/fetchFollowersByUserId.ts
+++ b/src/modules/users/fetchFollowersByUserId.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { User } from "../../interfaces/User";
 import { SpaceReputationUserParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 
 export interface FetchFollowersByUserIdProps extends SpaceReputationUserParams {
@@ -13,10 +14,25 @@ export async function fetchFollowersByUserId(
   client: SublayHttpClient,
   data: FetchFollowersByUserIdProps
 ): Promise<PaginatedResponse<User>> {
-  const { userId, ...params } = data;
+  const {
+    userId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<PaginatedResponse<User>>(
     `/users/${userId}/followers`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/users/fetchFollowingByUserId.ts b/src/modules/users/fetchFollowingByUserId.ts
index c9823e0..7331065 100644
--- a/src/modules/users/fetchFollowingByUserId.ts
+++ b/src/modules/users/fetchFollowingByUserId.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { User } from "../../interfaces/User";
 import { SpaceReputationUserParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 import { PaginatedResponse } from "../../interfaces/IPaginatedResponse";
 
 export interface FetchFollowingByUserIdProps extends SpaceReputationUserParams {
@@ -13,10 +14,25 @@ export async function fetchFollowingByUserId(
   client: SublayHttpClient,
   data: FetchFollowingByUserIdProps
 ): Promise<PaginatedResponse<User>> {
-  const { userId, ...params } = data;
+  const {
+    userId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const response = await client.projectInstance.get<PaginatedResponse<User>>(
     `/users/${userId}/following`,
-    { params }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }
diff --git a/src/modules/users/fetchUserByForeignId.ts b/src/modules/users/fetchUserByForeignId.ts
index c7a03cb..10c9807 100644
--- a/src/modules/users/fetchUserByForeignId.ts
+++ b/src/modules/users/fetchUserByForeignId.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { User } from "../../interfaces/User";
 import { SpaceReputationUserParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchUserByForeignIdProps extends SpaceReputationUserParams {
   foreignId: string;
@@ -32,8 +33,11 @@ export async function fetchUserByForeignId(
       ? JSON.stringify(data.secureMetadata)
       : undefined,
     include: data.include,
-    spaceReputationId: data.spaceReputationId,
-    spaceReputationDescendants: data.spaceReputationDescendants,
+    ...buildSpaceReputationParams({
+      spaceReputation: data.spaceReputation,
+      spaceReputationId: data.spaceReputationId,
+      spaceReputationDescendants: data.spaceReputationDescendants,
+    }),
   };
 
   const response = await client.projectInstance.get<User>(path, {
diff --git a/src/modules/users/fetchUserById.ts b/src/modules/users/fetchUserById.ts
index 962bb10..cefe244 100644
--- a/src/modules/users/fetchUserById.ts
+++ b/src/modules/users/fetchUserById.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { User } from "../../interfaces/User";
 import { SpaceReputationUserParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchUserByIdProps extends SpaceReputationUserParams {
   userId: string;
@@ -11,8 +12,23 @@ export async function fetchUserById(
   client: SublayHttpClient,
   data: FetchUserByIdProps
 ): Promise<User> {
-  const { userId, ...params } = data;
+  const {
+    userId,
+    spaceReputation,
+    spaceReputationId,
+    spaceReputationDescendants,
+    ...rest
+  } = data;
   const path = `/users/${userId}`; // assuming client handles prefix like /{projectId}
-  const response = await client.projectInstance.get<User>(path, { params });
+  const response = await client.projectInstance.get<User>(path, {
+    params: {
+      ...rest,
+      ...buildSpaceReputationParams({
+        spaceReputation,
+        spaceReputationId,
+        spaceReputationDescendants,
+      }),
+    },
+  });
   return response.data;
 }
diff --git a/src/modules/users/fetchUserByUsername.ts b/src/modules/users/fetchUserByUsername.ts
index d2ee031..411f66e 100644
--- a/src/modules/users/fetchUserByUsername.ts
+++ b/src/modules/users/fetchUserByUsername.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { User } from "../../interfaces/User";
 import { SpaceReputationUserParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchUserByUsernameProps extends SpaceReputationUserParams {
   username: string;
@@ -11,8 +12,17 @@ export async function fetchUserByUsername(
   client: SublayHttpClient,
   data: FetchUserByUsernameProps
 ): Promise<User> {
+  const { spaceReputation, spaceReputationId, spaceReputationDescendants, ...rest } =
+    data;
   const response = await client.projectInstance.get<User>("/users/by-username", {
-    params: data,
+    params: {
+      ...rest,
+      ...buildSpaceReputationParams({
+        spaceReputation,
+        spaceReputationId,
+        spaceReputationDescendants,
+      }),
+    },
   });
   return response.data;
 }
diff --git a/src/modules/users/fetchUserSuggestions.ts b/src/modules/users/fetchUserSuggestions.ts
index 05814dd..d14b8b0 100644
--- a/src/modules/users/fetchUserSuggestions.ts
+++ b/src/modules/users/fetchUserSuggestions.ts
@@ -1,6 +1,7 @@
 import { SublayHttpClient } from "../../core/client";
 import { User } from "../../interfaces/User";
 import { SpaceReputationUserParams } from "../../interfaces/SpaceReputation";
+import { buildSpaceReputationParams } from "../../core/spaceReputationParams";
 
 export interface FetchUserSuggestionsProps extends SpaceReputationUserParams {
   query: string;
@@ -10,9 +11,20 @@ export async function fetchUserSuggestions(
   client: SublayHttpClient,
   data: FetchUserSuggestionsProps
 ): Promise<User[]> {
+  const { spaceReputation, spaceReputationId, spaceReputationDescendants, ...rest } =
+    data;
   const response = await client.projectInstance.get<User[]>(
     "/users/suggestions",
-    { params: data }
+    {
+      params: {
+        ...rest,
+        ...buildSpaceReputationParams({
+          spaceReputation,
+          spaceReputationId,
+          spaceReputationDescendants,
+        }),
+      },
+    }
   );
   return response.data;
 }