diff --git a/README.md b/README.md
index d3aba92..4dd34fb 100644
--- a/README.md
+++ b/README.md
@@ -131,7 +131,7 @@ source.pipe(
   
   // Maps the events with
   // block and extrinsic context
-  mapEventsWithContext(),
+  extractEventsWithTx(),
   
   // Filters over the events
   mongoFilter(eventsQuery),
diff --git a/packages/core/src/operators/filter.ts b/packages/core/src/operators/filter.ts
index 94dd294..3b297f8 100644
--- a/packages/core/src/operators/filter.ts
+++ b/packages/core/src/operators/filter.ts
@@ -9,14 +9,16 @@ import { ControlQuery, Criteria } from '../index.js';
 import { EventWithId, TxWithIdAndEvent } from '../types/interfaces.js';
 
 /**
+ * Filters extrinsics based on the provided criteria.
  *
- * @param extrinsicsCriteria
- * @returns
+ * It extracts extrinsics with events from the given block,
+ * flattens batch calls if needed and applies the filter criteria.
+ *
+ * @param extrinsicsCriteria The criteria to filter extrinsics.
+ * @returns An observable that emits filtered extrinsics with identifier and event information.
  */
 export function filterExtrinsics(
-  extrinsicsCriteria : Criteria = {
-    dispatchError: { $exists: false }
-  }
+  extrinsicsCriteria: Criteria
 ) {
   return (source: Observable<SignedBlockExtended>)
     : Observable<TxWithIdAndEvent> => {
diff --git a/packages/core/src/subjects/query.ts b/packages/core/src/subjects/query.ts
index e44648e..71c7c9d 100644
--- a/packages/core/src/subjects/query.ts
+++ b/packages/core/src/subjects/query.ts
@@ -62,9 +62,9 @@ export class ControlQuery
   }
 
   /**
-   *
-   * @param obj
-   * @returns
+   * Checks if an object is an instance of `ControlQuery`.
+   * @param obj The object to check.
+   * @returns `true` if the object is an instance of `ControlQuery`, `false` otherwise.
    */
   static isControlQuery(obj: ControlQuery | Criteria): obj is ControlQuery {
     return obj.change !== undefined;
diff --git a/packages/pallets/contracts/src/operators/contracts.ts b/packages/pallets/contracts/src/operators/contracts.ts
index b3fa409..e897b84 100644
--- a/packages/pallets/contracts/src/operators/contracts.ts
+++ b/packages/pallets/contracts/src/operators/contracts.ts
@@ -21,8 +21,8 @@ function getArgValueFromTx(extrinsic: types.ExtrinsicWithId, name: string) {
  * Returns an Observable that filters for contract call extrinsics based on the given address
  * and decodes the contract message based on the provided ABI.
  *
- * @param abiJson - The ABI of the contract as a JSON object or string.
- * @param address - The address of the contract.
+ * @param abi The ABI of the contract as a JSON object or string.
+ * @param address The contract address or an array of addresses.
  * @returns An Observable that emits ContractMessageWithTx objects.
  */
 export function contractMessages(abi: Abi, address: AddressParam ) {
@@ -54,9 +54,9 @@ export function contractMessages(abi: Abi, address: AddressParam ) {
  * Returns an Observable that filters for contract instantiations based on the given code hash
  * and decodes the contract constructor based on the provided ABI.
  *
- * @param api - The ApiPromise instance for the network.
- * @param abi - The contract ABI.
- * @param codeHash - The contract code hash.
+ * @param api The ApiPromise instance for the network.
+ * @param abi The contract ABI.
+ * @param codeHash The contract code hash.
  *
  * @returns An observable that emits the decoded contract constructor with associated block event and transaction.
  */
@@ -123,8 +123,8 @@ export function contractConstructors(api: ApiPromise, abi: Abi, codeHash: string
 /**
  * Returns an Observable that filters and maps contract events based on the given ABI and address.
  *
- * @param abiJson - The ABI of the contract as a JSON object or string.
- * @param address - The address of the contract.
+ * @param abi The ABI of the contract as a JSON object or string.
+ * @param address The contract address or an array of addresses.
  * @returns An Observable that emits ContractEventWithBlockEvent objects.
  */
 export function contractEvents(
diff --git a/packages/pallets/contracts/src/operators/filter.ts b/packages/pallets/contracts/src/operators/filter.ts
index ff25c95..9dd8f3a 100644
--- a/packages/pallets/contracts/src/operators/filter.ts
+++ b/packages/pallets/contracts/src/operators/filter.ts
@@ -16,7 +16,13 @@ import { ContractEventWithBlockEvent, ContractMessageWithTx } from '../types/int
 import { AddressParam } from '../types/types.js';
 
 /**
+ * Filters contract calls based on the provided criteria.
  *
+ * @param abi The ABI of the contract as a JSON object or string.
+ * @param address The contract address or an array of addresses.
+ * @param callsCriteria The criteria to filter contract calls.
+ * @param extrinsicsCriteria - (Optional) Criteria for filtering extrinsics. Defaults to `{ dispatchError: { $exists: false } }`.
+ * @returns An observable that emits filtered contract calls.
  */
 export function filterContractCalls(
   abi: Abi,
@@ -43,12 +49,13 @@ export function filterContractCalls(
 }
 
 /**
+ * Filters contract events based on the provided criteria.
  *
- * @param abi
- * @param address
- * @param eventsCriteria
- * @param extrinsicsCriteria
- * @returns
+ * @param abi The ABI of the contract as a JSON object or string.
+ * @param address The contract address or an array of addresses.
+ * @param eventsCriteria The criteria to filter contract events.
+ * @param extrinsicsCriteria - (Optional) Criteria for filtering extrinsics. Defaults to `{ dispatchError: { $exists: false } }`.
+ * @returns An observable that emits filtered contract events.
  */
 export function filterContractEvents(
   abi: Abi,