diff --git a/packages/account-wasm/pkg/account_wasm_bg.js b/packages/account-wasm/pkg/account_wasm_bg.js
index c205dc2b6..faef5df8e 100644
--- a/packages/account-wasm/pkg/account_wasm_bg.js
+++ b/packages/account-wasm/pkg/account_wasm_bg.js
@@ -457,16 +457,6 @@ export function __wbindgen_string_get(arg0, arg1) {
     getInt32Memory0()[arg0 / 4 + 0] = ptr1;
 };
 
-export function __wbindgen_cb_drop(arg0) {
-    const obj = takeObject(arg0).original;
-    if (obj.cnt-- == 1) {
-        obj.a = 0;
-        return true;
-    }
-    const ret = false;
-    return ret;
-};
-
 export function __wbindgen_is_bigint(arg0) {
     const ret = typeof(getObject(arg0)) === 'bigint';
     return ret;
@@ -516,6 +506,16 @@ export function __wbindgen_is_undefined(arg0) {
     return ret;
 };
 
+export function __wbindgen_cb_drop(arg0) {
+    const obj = takeObject(arg0).original;
+    if (obj.cnt-- == 1) {
+        obj.a = 0;
+        return true;
+    }
+    const ret = false;
+    return ret;
+};
+
 export function __wbindgen_jsval_loose_eq(arg0, arg1) {
     const ret = getObject(arg0) == getObject(arg1);
     return ret;
@@ -561,64 +561,21 @@ export function __wbg_String_88810dfeb4021902(arg0, arg1) {
     getInt32Memory0()[arg0 / 4 + 0] = ptr1;
 };
 
-export function __wbg_crypto_1d1f22824a6a080c(arg0) {
-    const ret = getObject(arg0).crypto;
-    return addHeapObject(ret);
-};
-
-export function __wbg_process_4a72847cc503995b(arg0) {
-    const ret = getObject(arg0).process;
-    return addHeapObject(ret);
-};
-
-export function __wbg_versions_f686565e586dd935(arg0) {
-    const ret = getObject(arg0).versions;
+export function __wbg_fetch_bc7c8e27076a5c84(arg0) {
+    const ret = fetch(getObject(arg0));
     return addHeapObject(ret);
 };
 
-export function __wbg_node_104a2ff8d6ea03a2(arg0) {
-    const ret = getObject(arg0).node;
+export function __wbg_queueMicrotask_3cbae2ec6b6cd3d6(arg0) {
+    const ret = getObject(arg0).queueMicrotask;
     return addHeapObject(ret);
 };
 
-export function __wbindgen_is_string(arg0) {
-    const ret = typeof(getObject(arg0)) === 'string';
-    return ret;
-};
-
-export function __wbg_require_cca90b1a94a0255b() { return handleError(function () {
-    const ret = module.require;
-    return addHeapObject(ret);
-}, arguments) };
-
 export function __wbindgen_is_function(arg0) {
     const ret = typeof(getObject(arg0)) === 'function';
     return ret;
 };
 
-export function __wbg_msCrypto_eb05e62b530a1508(arg0) {
-    const ret = getObject(arg0).msCrypto;
-    return addHeapObject(ret);
-};
-
-export function __wbg_randomFillSync_5c9c955aa56b6049() { return handleError(function (arg0, arg1) {
-    getObject(arg0).randomFillSync(takeObject(arg1));
-}, arguments) };
-
-export function __wbg_getRandomValues_3aa56aa6edec874c() { return handleError(function (arg0, arg1) {
-    getObject(arg0).getRandomValues(getObject(arg1));
-}, arguments) };
-
-export function __wbg_fetch_bc7c8e27076a5c84(arg0) {
-    const ret = fetch(getObject(arg0));
-    return addHeapObject(ret);
-};
-
-export function __wbg_queueMicrotask_3cbae2ec6b6cd3d6(arg0) {
-    const ret = getObject(arg0).queueMicrotask;
-    return addHeapObject(ret);
-};
-
 export function __wbg_queueMicrotask_481971b0d87f3dd4(arg0) {
     queueMicrotask(getObject(arg0));
 };
@@ -753,6 +710,49 @@ export function __wbg_hostname_3d9f22c60dc5bec6() { return handleError(function
     getInt32Memory0()[arg0 / 4 + 0] = ptr1;
 }, arguments) };
 
+export function __wbg_crypto_1d1f22824a6a080c(arg0) {
+    const ret = getObject(arg0).crypto;
+    return addHeapObject(ret);
+};
+
+export function __wbg_process_4a72847cc503995b(arg0) {
+    const ret = getObject(arg0).process;
+    return addHeapObject(ret);
+};
+
+export function __wbg_versions_f686565e586dd935(arg0) {
+    const ret = getObject(arg0).versions;
+    return addHeapObject(ret);
+};
+
+export function __wbg_node_104a2ff8d6ea03a2(arg0) {
+    const ret = getObject(arg0).node;
+    return addHeapObject(ret);
+};
+
+export function __wbindgen_is_string(arg0) {
+    const ret = typeof(getObject(arg0)) === 'string';
+    return ret;
+};
+
+export function __wbg_require_cca90b1a94a0255b() { return handleError(function () {
+    const ret = module.require;
+    return addHeapObject(ret);
+}, arguments) };
+
+export function __wbg_msCrypto_eb05e62b530a1508(arg0) {
+    const ret = getObject(arg0).msCrypto;
+    return addHeapObject(ret);
+};
+
+export function __wbg_randomFillSync_5c9c955aa56b6049() { return handleError(function (arg0, arg1) {
+    getObject(arg0).randomFillSync(takeObject(arg1));
+}, arguments) };
+
+export function __wbg_getRandomValues_3aa56aa6edec874c() { return handleError(function (arg0, arg1) {
+    getObject(arg0).getRandomValues(getObject(arg1));
+}, arguments) };
+
 export function __wbg_get_bd8e338fbd5f5cc8(arg0, arg1) {
     const ret = getObject(arg0)[arg1 >>> 0];
     return addHeapObject(ret);
@@ -1002,8 +1002,8 @@ export function __wbindgen_memory() {
     return addHeapObject(ret);
 };
 
-export function __wbindgen_closure_wrapper1626(arg0, arg1, arg2) {
-    const ret = makeMutClosure(arg0, arg1, 500, __wbg_adapter_48);
+export function __wbindgen_closure_wrapper1507(arg0, arg1, arg2) {
+    const ret = makeMutClosure(arg0, arg1, 513, __wbg_adapter_48);
     return addHeapObject(ret);
 };
 
diff --git a/packages/account-wasm/pkg/account_wasm_bg.wasm b/packages/account-wasm/pkg/account_wasm_bg.wasm
index 02c754a8a..c0713a8cd 100644
Binary files a/packages/account-wasm/pkg/account_wasm_bg.wasm and b/packages/account-wasm/pkg/account_wasm_bg.wasm differ
diff --git a/packages/account-wasm/src/errors.rs b/packages/account-wasm/src/errors.rs
new file mode 100644
index 000000000..cce4fee91
--- /dev/null
+++ b/packages/account-wasm/src/errors.rs
@@ -0,0 +1,71 @@
+use account_sdk::signers::SignError;
+use base64::DecodeError;
+use coset::CoseError;
+use starknet::{
+    accounts::AccountError,
+    core::{types::FromStrError, utils::NonAsciiNameError},
+};
+use thiserror::Error;
+
+#[derive(Error, Debug)]
+pub enum CartridgeError {
+    #[error("Session error: {0}")]
+    Session(#[from] SessionError),
+
+    #[error("Account operation error: {0}")]
+    Operation(#[from] OperationError),
+
+    #[error("Encoding error: {0}")]
+    Encoding(#[from] EncodingError),
+}
+
+#[derive(Error, Debug)]
+pub enum SessionError {
+    #[error("Failed to create session: {0}")]
+    Creation(SignError),
+
+    #[error("Failed to sign message: {0}")]
+    Signing(SignError),
+}
+
+#[derive(Error, Debug)]
+pub enum OperationError {
+    #[error("Failed to delegate account: {0}")]
+    Delegation(String),
+
+    #[error("Failed to estimate fee: {0}")]
+    FeeEstimation(String),
+
+    #[error("Failed to execute transaction: {0}")]
+    Execution(String),
+
+    #[error("Failed to deploy account: {0}")]
+    Deployment(String),
+
+    #[error("Failed to sign message: {0}")]
+    SignMessage(SignError),
+
+    #[error(transparent)]
+    AccountError(#[from] AccountError<SignError>),
+}
+
+#[derive(Error, Debug)]
+pub enum EncodingError {
+    #[error(transparent)]
+    FromStr(#[from] FromStrError),
+
+    #[error(transparent)]
+    NonAsciiName(#[from] NonAsciiNameError),
+
+    #[error("Base64 decoding error: {0}")]
+    Base64Decode(#[from] DecodeError),
+
+    #[error("COSE key error: {0}")]
+    CoseKey(#[from] CoseError),
+
+    #[error("Invalid JSON: {0}")]
+    Json(#[from] serde_json::Error),
+
+    #[error("Serialization error: {0}")]
+    Serialization(#[from] serde_wasm_bindgen::Error),
+}
diff --git a/packages/account-wasm/src/lib.rs b/packages/account-wasm/src/lib.rs
index e59165e42..bda9e3d6f 100644
--- a/packages/account-wasm/src/lib.rs
+++ b/packages/account-wasm/src/lib.rs
@@ -1,4 +1,5 @@
 mod constants;
+mod errors;
 mod paymaster;
 mod types;
 mod utils;
@@ -26,6 +27,7 @@ use base64::{engine::general_purpose, Engine};
 use cainome::cairo_serde::CairoSerde;
 use constants::ACCOUNT_CLASS_HASH;
 use coset::{CborSerializable, CoseKey};
+use errors::{OperationError, SessionError};
 use factory::cartridge::CartridgeAccountFactory;
 use factory::AccountDeployment;
 use paymaster::PaymasterRequest;
@@ -128,16 +130,21 @@ impl CartridgeAccount {
         let methods = policies
             .into_iter()
             .map(AllowedMethod::try_from_js_value)
-            .collect::<Result<Vec<AllowedMethod>>>()?;
+            .collect::<std::result::Result<Vec<_>, _>>()?;
 
         let signer = SigningKey::from_random();
-        let session = Session::new(methods, expires_at, &signer.signer())?;
+        let session =
+            Session::new(methods, expires_at, &signer.signer()).map_err(SessionError::Creation)?;
 
         let hash = session
             .raw()
             .get_message_hash_rev_1(self.account.chain_id(), self.account.address());
 
-        let authorization = self.account.sign_hash(hash).await?;
+        let authorization = self
+            .account
+            .sign_hash(hash)
+            .await
+            .map_err(SessionError::Signing)?;
 
         Ok(to_value(&JsCredentials {
             authorization,
@@ -157,23 +164,26 @@ impl CartridgeAccount {
         let calls = calls
             .into_iter()
             .map(Call::try_from_js_value)
-            .collect::<Result<Vec<Call>>>()?;
+            .collect::<std::result::Result<Vec<_>, _>>()?;
 
-        let fee_estimate = if let Some(session_details) = from_value(session_details)? {
+        let result = if let Some(session_details) = from_value(session_details)? {
             self.session_account(session_details)
                 .await?
                 .execute_v1(calls)
                 .fee_estimate_multiplier(fee_multiplier.unwrap_or(1.0))
                 .estimate_fee()
-                .await?
+                .await
         } else {
             self.account
                 .execute_v1(calls)
                 .fee_estimate_multiplier(fee_multiplier.unwrap_or(1.0))
                 .estimate_fee()
-                .await?
+                .await
         };
 
+        let fee_estimate =
+            result.map_err(|e| OperationError::FeeEstimation(format!("{:#?}", e)))?;
+
         Ok(to_value(&fee_estimate)?)
     }
 
@@ -189,26 +199,28 @@ impl CartridgeAccount {
         let calls = calls
             .into_iter()
             .map(Call::try_from_js_value)
-            .collect::<Result<Vec<Call>>>()?;
+            .collect::<std::result::Result<Vec<_>, _>>()?;
 
         let details = JsInvocationsDetails::try_from(transaction_details)?;
-        let execution = if let Some(session_details) = from_value(session_details)? {
+        let result = if let Some(session_details) = from_value(session_details)? {
             self.session_account(session_details)
                 .await?
                 .execute_v1(calls)
                 .max_fee(details.max_fee)
                 .nonce(details.nonce)
                 .send()
-                .await?
+                .await
         } else {
             self.account
                 .execute_v1(calls)
                 .max_fee(details.max_fee)
                 .nonce(details.nonce)
                 .send()
-                .await?
+                .await
         };
 
+        let execution = result.map_err(|e| OperationError::Execution(format!("{:#?}", e)))?;
+
         Ok(to_value(&execution)?)
     }
 
@@ -228,7 +240,7 @@ impl CartridgeAccount {
             calls: calls
                 .into_iter()
                 .map(JsCall::try_from)
-                .collect::<Result<Vec<JsCall>>>()?,
+                .collect::<std::result::Result<Vec<_>, _>>()?,
             nonce: SigningKey::from_random().secret_scalar(),
         };
 
@@ -265,7 +277,9 @@ impl CartridgeAccount {
         let signature = self
             .account
             .sign_message(serde_json::from_str(&typed_data)?)
-            .await?;
+            .await
+            .map_err(OperationError::SignMessage)?;
+
         Ok(to_value(&signature)?)
     }
 
@@ -289,8 +303,11 @@ impl CartridgeAccount {
             starknetutils::cairo_short_string_to_felt(&self.username)?,
             &factory,
         );
-        let res: starknet::core::types::DeployAccountTransactionResult =
-            deployment.max_fee(from_value(max_fee)?).send().await?;
+        let res = deployment
+            .max_fee(from_value(max_fee)?)
+            .send()
+            .await
+            .map_err(|e| OperationError::Deployment(format!("{:#?}", e)))?;
 
         Ok(to_value(&res)?)
     }
@@ -308,7 +325,9 @@ impl CartridgeAccount {
                 },
                 BlockId::Tag(BlockTag::Pending),
             )
-            .await?;
+            .await
+            .map_err(|e| OperationError::Delegation(e.to_string()))?;
+
         Ok(to_value(&res[0])?)
     }
 
@@ -325,7 +344,8 @@ impl CartridgeAccount {
         let dummy_guardian = SigningKey::from_secret_scalar(short_string!("CARTRIDGE_GUARDIAN"));
         let session_signer = SigningKey::from_secret_scalar(details.credentials.private_key);
         let expires_at: u64 = details.expires_at.parse()?;
-        let session = Session::new(methods, expires_at, &session_signer.signer())?;
+        let session = Session::new(methods, expires_at, &session_signer.signer())
+            .map_err(SessionError::Creation)?;
 
         Ok(SessionAccount::new(
             JsonRpcClient::new(HttpTransport::new(self.rpc_url.clone())),
diff --git a/packages/account-wasm/src/types/call.rs b/packages/account-wasm/src/types/call.rs
index 3a3d979f6..332055315 100644
--- a/packages/account-wasm/src/types/call.rs
+++ b/packages/account-wasm/src/types/call.rs
@@ -7,6 +7,8 @@ use starknet::{
 };
 use wasm_bindgen::prelude::*;
 
+use crate::errors::EncodingError;
+
 use super::TryFromJsValue;
 
 #[serde_as]
@@ -21,7 +23,7 @@ pub struct JsCall {
 }
 
 impl TryFrom<JsCall> for Call {
-    type Error = JsError;
+    type Error = EncodingError;
 
     fn try_from(value: JsCall) -> Result<Self, Self::Error> {
         Ok(Call {
@@ -33,7 +35,7 @@ impl TryFrom<JsCall> for Call {
 }
 
 impl TryFrom<JsValue> for JsCall {
-    type Error = JsError;
+    type Error = EncodingError;
 
     fn try_from(value: JsValue) -> Result<Self, Self::Error> {
         Ok(serde_wasm_bindgen::from_value(value)?)
@@ -41,7 +43,7 @@ impl TryFrom<JsValue> for JsCall {
 }
 
 impl TryFromJsValue<Call> for Call {
-    fn try_from_js_value(value: JsValue) -> Result<Self, JsError> {
+    fn try_from_js_value(value: JsValue) -> Result<Self, EncodingError> {
         let js_call: JsCall = value.try_into()?;
         js_call.try_into()
     }
diff --git a/packages/account-wasm/src/types/estimate.rs b/packages/account-wasm/src/types/estimate.rs
index a07bbbca4..7bd100c5b 100644
--- a/packages/account-wasm/src/types/estimate.rs
+++ b/packages/account-wasm/src/types/estimate.rs
@@ -3,6 +3,8 @@ use serde_with::serde_as;
 use starknet::core::{serde::unsigned_field_element::UfeHex, types::Felt};
 use wasm_bindgen::prelude::*;
 
+use crate::errors::EncodingError;
+
 #[serde_as]
 #[derive(Debug, Deserialize, Serialize)]
 #[serde(rename_all = "camelCase")]
@@ -12,7 +14,7 @@ pub struct JsEstimateFeeDetails {
 }
 
 impl TryFrom<JsValue> for JsEstimateFeeDetails {
-    type Error = JsError;
+    type Error = EncodingError;
 
     fn try_from(value: JsValue) -> Result<Self, Self::Error> {
         Ok(serde_wasm_bindgen::from_value(value)?)
diff --git a/packages/account-wasm/src/types/invocation.rs b/packages/account-wasm/src/types/invocation.rs
index c9db1c262..a7ea881c3 100644
--- a/packages/account-wasm/src/types/invocation.rs
+++ b/packages/account-wasm/src/types/invocation.rs
@@ -4,6 +4,8 @@ use starknet::core::serde::unsigned_field_element::UfeHex;
 use starknet::core::types::Felt;
 use wasm_bindgen::prelude::*;
 
+use crate::errors::EncodingError;
+
 #[serde_as]
 #[derive(Debug, Deserialize, Serialize)]
 #[serde(rename_all = "camelCase")]
@@ -15,7 +17,7 @@ pub struct JsInvocationsDetails {
 }
 
 impl TryFrom<JsValue> for JsInvocationsDetails {
-    type Error = JsError;
+    type Error = EncodingError;
 
     fn try_from(value: JsValue) -> Result<Self, Self::Error> {
         Ok(serde_wasm_bindgen::from_value(value)?)
diff --git a/packages/account-wasm/src/types/mod.rs b/packages/account-wasm/src/types/mod.rs
index e4339b1c0..c6cca4d00 100644
--- a/packages/account-wasm/src/types/mod.rs
+++ b/packages/account-wasm/src/types/mod.rs
@@ -1,4 +1,6 @@
-use wasm_bindgen::{JsError, JsValue};
+use wasm_bindgen::JsValue;
+
+use crate::errors::EncodingError;
 
 pub(crate) mod call;
 pub(crate) mod estimate;
@@ -8,5 +10,5 @@ pub(crate) mod policy;
 pub(crate) mod session;
 
 pub(crate) trait TryFromJsValue<T> {
-    fn try_from_js_value(value: JsValue) -> Result<T, JsError>;
+    fn try_from_js_value(value: JsValue) -> Result<T, EncodingError>;
 }
diff --git a/packages/account-wasm/src/types/outside_execution.rs b/packages/account-wasm/src/types/outside_execution.rs
index b6827eb29..a155ea092 100644
--- a/packages/account-wasm/src/types/outside_execution.rs
+++ b/packages/account-wasm/src/types/outside_execution.rs
@@ -6,6 +6,8 @@ use starknet::macros::short_string;
 use starknet::{accounts::Call, core::types::Felt};
 use wasm_bindgen::prelude::*;
 
+use crate::errors::EncodingError;
+
 use super::call::JsCall;
 
 #[serde_as]
@@ -22,7 +24,7 @@ pub struct JsOutsideExecution {
 }
 
 impl TryFrom<JsValue> for JsOutsideExecution {
-    type Error = JsError;
+    type Error = EncodingError;
 
     fn try_from(value: JsValue) -> Result<Self, Self::Error> {
         Ok(serde_wasm_bindgen::from_value(value)?)
@@ -30,7 +32,7 @@ impl TryFrom<JsValue> for JsOutsideExecution {
 }
 
 impl TryFrom<JsOutsideExecution> for OutsideExecution {
-    type Error = JsError;
+    type Error = EncodingError;
 
     fn try_from(value: JsOutsideExecution) -> Result<Self, Self::Error> {
         let caller = if value.caller.eq(&short_string!("ANY_CALLER")) {
diff --git a/packages/account-wasm/src/types/policy.rs b/packages/account-wasm/src/types/policy.rs
index 0d93d8640..746108755 100644
--- a/packages/account-wasm/src/types/policy.rs
+++ b/packages/account-wasm/src/types/policy.rs
@@ -1,12 +1,11 @@
 use account_sdk::account::session::hash::AllowedMethod;
 use serde::{Deserialize, Serialize};
-use starknet::core::{
-    types::{Felt, FromStrError},
-    utils::get_selector_from_name,
-};
+use starknet::core::{types::Felt, utils::get_selector_from_name};
 use std::str::FromStr;
 use wasm_bindgen::prelude::*;
 
+use crate::errors::EncodingError;
+
 use super::TryFromJsValue;
 
 #[derive(Clone, Debug, Deserialize, Serialize)]
@@ -17,7 +16,7 @@ pub struct JsPolicy {
 }
 
 impl TryFrom<JsValue> for JsPolicy {
-    type Error = JsError;
+    type Error = EncodingError;
 
     fn try_from(value: JsValue) -> Result<Self, Self::Error> {
         Ok(serde_wasm_bindgen::from_value(value)?)
@@ -25,7 +24,7 @@ impl TryFrom<JsValue> for JsPolicy {
 }
 
 impl TryFrom<JsPolicy> for AllowedMethod {
-    type Error = FromStrError;
+    type Error = EncodingError;
 
     fn try_from(value: JsPolicy) -> Result<Self, Self::Error> {
         Ok(AllowedMethod {
@@ -36,7 +35,7 @@ impl TryFrom<JsPolicy> for AllowedMethod {
 }
 
 impl TryFromJsValue<AllowedMethod> for AllowedMethod {
-    fn try_from_js_value(value: JsValue) -> Result<Self, JsError> {
+    fn try_from_js_value(value: JsValue) -> Result<Self, EncodingError> {
         let js_policy: JsPolicy = value.try_into()?;
         let allowed_method: AllowedMethod = js_policy.try_into()?;
         Ok(allowed_method)