Fix: Inconsistent Error Messages.

CLAUDE.md

@@ -0,0 +1 @@
+# CLAUDE.md

contracts/compliance_registry/lib.rs

@@ -1,11 +1,8 @@
 #![cfg_attr(not(feature = "std"), no_std, no_main)]
-#![allow(clippy::needless_borrows_for_generic_args)]
-#![allow(clippy::too_many_arguments)]
-#![allow(clippy::upper_case_acronyms)]
 #![allow(
-    clippy::upper_case_acronyms,
+    clippy::needless_borrows_for_generic_args,
     clippy::too_many_arguments,
-    clippy::needless_borrows_for_generic_args
+    clippy::upper_case_acronyms
 )]
 
 use propchain_traits::ComplianceChecker;
@@ -383,53 +380,79 @@ mod compliance_registry {
                     propchain_traits::errors::compliance_codes::COMPLIANCE_EXPIRED
                 }
                 Error::HighRisk => {
-                    propchain_traits::errors::compliance_codes::COMPLIANCE_CHECK_FAILED
+                    propchain_traits::errors::compliance_codes::COMPLIANCE_HIGH_RISK
                 }
                 Error::ProhibitedJurisdiction => {
-                    propchain_traits::errors::compliance_codes::COMPLIANCE_CHECK_FAILED
+                    propchain_traits::errors::compliance_codes::COMPLIANCE_PROHIBITED_JURISDICTION
                 }
                 Error::AlreadyVerified => {
-                    propchain_traits::errors::compliance_codes::COMPLIANCE_UNAUTHORIZED
+                    propchain_traits::errors::compliance_codes::COMPLIANCE_ALREADY_VERIFIED
                 }
                 Error::ConsentNotGiven => {
-                    propchain_traits::errors::compliance_codes::COMPLIANCE_NOT_VERIFIED
+                    propchain_traits::errors::compliance_codes::COMPLIANCE_CONSENT_NOT_GIVEN
                 }
                 Error::DataRetentionExpired => {
-                    propchain_traits::errors::compliance_codes::COMPLIANCE_EXPIRED
+                    propchain_traits::errors::compliance_codes::COMPLIANCE_DATA_RETENTION_EXPIRED
                 }
                 Error::InvalidRiskScore => {
-                    propchain_traits::errors::compliance_codes::COMPLIANCE_CHECK_FAILED
+                    propchain_traits::errors::compliance_codes::COMPLIANCE_INVALID_RISK_SCORE
                 }
                 Error::InvalidDocumentType => {
-                    propchain_traits::errors::compliance_codes::COMPLIANCE_DOCUMENT_MISSING
+                    propchain_traits::errors::compliance_codes::COMPLIANCE_INVALID_DOCUMENT_TYPE
                 }
                 Error::JurisdictionNotSupported => {
-                    propchain_traits::errors::compliance_codes::COMPLIANCE_CHECK_FAILED
+                    propchain_traits::errors::compliance_codes::COMPLIANCE_JURISDICTION_NOT_SUPPORTED
                 }
             }
         }
 
         fn error_description(&self) -> &'static str {
             match self {
-                Error::NotAuthorized => "Caller does not have permission to perform this operation",
+                Error::NotAuthorized => {
+                    "Caller does not have permission to perform this compliance operation"
+                }
                 Error::NotVerified => "The user has not completed verification",
                 Error::VerificationExpired => {
                     "The user's verification has expired and needs renewal"
                 }
-                Error::HighRisk => "The user has been assessed as high risk",
-                Error::ProhibitedJurisdiction => "The user's jurisdiction is prohibited",
-                Error::AlreadyVerified => "The user is already verified",
-                Error::ConsentNotGiven => "The user has not provided required consent",
-                Error::DataRetentionExpired => "The data retention period has expired",
-                Error::InvalidRiskScore => "The risk score is invalid or out of range",
-                Error::InvalidDocumentType => "The document type is invalid or not supported",
-                Error::JurisdictionNotSupported => "The jurisdiction is not supported",
+                Error::HighRisk => "The user has been assessed as high risk and is not permitted",
+                Error::ProhibitedJurisdiction => {
+                    "The user's jurisdiction is prohibited from this operation"
+                }
+                Error::AlreadyVerified => "The user is already verified and cannot be re-verified",
+                Error::ConsentNotGiven => "The user has not provided the required consent",
+                Error::DataRetentionExpired => {
+                    "The data retention period for this record has expired"
+                }
+                Error::InvalidRiskScore => {
+                    "The risk score provided is invalid or out of acceptable range"
+                }
+                Error::InvalidDocumentType => "The document type is invalid or not accepted",
+                Error::JurisdictionNotSupported => {
+                    "The specified jurisdiction is not currently supported"
+                }
             }
         }
 
         fn error_category(&self) -> ErrorCategory {
             ErrorCategory::Compliance
         }
+
+        fn error_i18n_key(&self) -> &'static str {
+            match self {
+                Error::NotAuthorized => "compliance.unauthorized",
+                Error::NotVerified => "compliance.not_verified",
+                Error::VerificationExpired => "compliance.verification_expired",
+                Error::HighRisk => "compliance.high_risk",
+                Error::ProhibitedJurisdiction => "compliance.prohibited_jurisdiction",
+                Error::AlreadyVerified => "compliance.already_verified",
+                Error::ConsentNotGiven => "compliance.consent_not_given",
+                Error::DataRetentionExpired => "compliance.data_retention_expired",
+                Error::InvalidRiskScore => "compliance.invalid_risk_score",
+                Error::InvalidDocumentType => "compliance.invalid_document_type",
+                Error::JurisdictionNotSupported => "compliance.jurisdiction_not_supported",
+            }
+        }
     }
 
     pub type Result<T> = core::result::Result<T, Error>;

contracts/traits/src/errors.rs

@@ -5,16 +5,40 @@
 //! - Common error variants reusable across contracts
 //! - Numeric error codes for external API integration
 //! - Full Debug, Display, and From trait implementations
+//! - [`ErrorMessage`]: structured error snapshot combining code, category, message, and i18n key
+//! - [`ContractError::to_error_message()`]: default method to produce an `ErrorMessage`
+//! - [`ContractError::error_i18n_key()`]: default method returning a localization key
 
 use core::fmt;
 use scale::{Decode, Encode};
 
 #[cfg(feature = "std")]
 use scale_info::TypeInfo;
 
-/// =============================================================================
-/// Base Error Trait
-/// =============================================================================
+// =============================================================================
+// Standardized Error Message
+// =============================================================================
+
+/// Structured snapshot of all error information for a single error instance.
+///
+/// Suitable for logging and client-side display. All string fields are `&'static str`
+/// for `no_std` / no-heap compatibility. This type is not SCALE-encoded since
+/// `&'static str` does not implement `Decode`; use it purely in-memory.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct ErrorMessage {
+    /// Numeric error code, globally unique across all PropChain contracts.
+    pub code: u32,
+    /// Top-level domain that produced this error.
+    pub category: ErrorCategory,
+    /// Short human-readable message (matches `error_description`).
+    pub message: &'static str,
+    /// Longer technical description suitable for logs and developer tooling.
+    pub description: &'static str,
+    /// Dot-separated localization key for client-side message lookup.
+    /// Format: `"<category>.<variant_snake_case>"`, e.g. `"compliance.not_verified"`.
+    pub i18n_key: &'static str,
+}
+
 // =============================================================================
 // Base Error Trait
 // =============================================================================
@@ -45,6 +69,26 @@ pub trait ContractError: fmt::Debug + fmt::Display + Encode + Decode {
             _ => ErrorCategory::Unknown,
         }
     }
+
+    /// Returns a dot-separated localization key for client-side message lookup.
+    ///
+    /// Format: `"<category>.<variant_snake_case>"`, e.g. `"compliance.not_verified"`.
+    /// Override this in each error type to provide a precise key.
+    fn error_i18n_key(&self) -> &'static str {
+        "unknown.error"
+    }
+
+    /// Constructs a complete [`ErrorMessage`] snapshot from this error.
+    /// No allocation is performed; all fields are `'static`.
+    fn to_error_message(&self) -> ErrorMessage {
+        ErrorMessage {
+            code: self.error_code(),
+            category: self.error_category(),
+            message: self.error_description(),
+            description: self.error_description(),
+            i18n_key: self.error_i18n_key(),
+        }
+    }
 }
 
 /// Error categories for classification and monitoring
@@ -82,9 +126,6 @@ impl fmt::Display for ErrorCategory {
     }
 }
 
-/// =============================================================================
-/// Common Error Variants
-/// =============================================================================
 // =============================================================================
 // Common Error Variants
 // =============================================================================
@@ -159,11 +200,23 @@ impl ContractError for CommonError {
     fn error_category(&self) -> ErrorCategory {
         ErrorCategory::Common
     }
+
+    fn error_i18n_key(&self) -> &'static str {
+        match self {
+            CommonError::Unauthorized => "common.unauthorized",
+            CommonError::InvalidParameters => "common.invalid_parameters",
+            CommonError::NotFound => "common.not_found",
+            CommonError::InsufficientFunds => "common.insufficient_funds",
+            CommonError::InvalidState => "common.invalid_state",
+            CommonError::InternalError => "common.internal_error",
+            CommonError::CodecError => "common.codec_error",
+            CommonError::NotImplemented => "common.not_implemented",
+            CommonError::Timeout => "common.timeout",
+            CommonError::Duplicate => "common.duplicate",
+        }
+    }
 }
 
-/// =============================================================================
-/// Error Code Constants
-/// =============================================================================
 // =============================================================================
 // Error Code Constants
 // =============================================================================
@@ -257,6 +310,7 @@ pub mod oracle_codes {
     pub const ORACLE_INSUFFICIENT_REPUTATION: u32 = 4009;
     pub const ORACLE_SOURCE_ALREADY_EXISTS: u32 = 4010;
     pub const ORACLE_REQUEST_PENDING: u32 = 4011;
+    pub const ORACLE_BATCH_SIZE_EXCEEDED: u32 = 4012;
 }
 
 /// Fee error codes (5000-5999)
@@ -278,6 +332,14 @@ pub mod compliance_codes {
     pub const COMPLIANCE_CHECK_FAILED: u32 = 6003;
     pub const COMPLIANCE_DOCUMENT_MISSING: u32 = 6004;
     pub const COMPLIANCE_EXPIRED: u32 = 6005;
+    pub const COMPLIANCE_HIGH_RISK: u32 = 6006;
+    pub const COMPLIANCE_PROHIBITED_JURISDICTION: u32 = 6007;
+    pub const COMPLIANCE_ALREADY_VERIFIED: u32 = 6008;
+    pub const COMPLIANCE_CONSENT_NOT_GIVEN: u32 = 6009;
+    pub const COMPLIANCE_INVALID_RISK_SCORE: u32 = 6010;
+    pub const COMPLIANCE_JURISDICTION_NOT_SUPPORTED: u32 = 6011;
+    pub const COMPLIANCE_INVALID_DOCUMENT_TYPE: u32 = 6012;
+    pub const COMPLIANCE_DATA_RETENTION_EXPIRED: u32 = 6013;
 }
 
 /// Governance error codes (7000-7999)
@@ -319,3 +381,59 @@ pub mod monitoring_codes {
     pub const MONITORING_SUBSCRIBER_LIMIT_REACHED: u32 = 9004;
     pub const MONITORING_SUBSCRIBER_NOT_FOUND: u32 = 9005;
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn common_error_i18n_keys_are_correct() {
+        assert_eq!(
+            CommonError::Unauthorized.error_i18n_key(),
+            "common.unauthorized"
+        );
+        assert_eq!(CommonError::NotFound.error_i18n_key(), "common.not_found");
+        assert_eq!(CommonError::Duplicate.error_i18n_key(), "common.duplicate");
+    }
+
+    #[test]
+    fn to_error_message_populates_all_fields() {
+        let msg = CommonError::Unauthorized.to_error_message();
+        assert_eq!(msg.code, common_codes::UNAUTHORIZED);
+        assert_eq!(msg.category, ErrorCategory::Common);
+        assert_eq!(msg.i18n_key, "common.unauthorized");
+        assert!(!msg.description.is_empty());
+    }
+
+    #[test]
+    fn oracle_batch_size_exceeded_constant_matches_value() {
+        assert_eq!(oracle_codes::ORACLE_BATCH_SIZE_EXCEEDED, 4012);
+    }
+
+    #[test]
+    fn compliance_codes_are_unique() {
+        let mut codes = vec![
+            compliance_codes::COMPLIANCE_UNAUTHORIZED,
+            compliance_codes::COMPLIANCE_NOT_VERIFIED,
+            compliance_codes::COMPLIANCE_CHECK_FAILED,
+            compliance_codes::COMPLIANCE_DOCUMENT_MISSING,
+            compliance_codes::COMPLIANCE_EXPIRED,
+            compliance_codes::COMPLIANCE_HIGH_RISK,
+            compliance_codes::COMPLIANCE_PROHIBITED_JURISDICTION,
+            compliance_codes::COMPLIANCE_ALREADY_VERIFIED,
+            compliance_codes::COMPLIANCE_CONSENT_NOT_GIVEN,
+            compliance_codes::COMPLIANCE_INVALID_RISK_SCORE,
+            compliance_codes::COMPLIANCE_JURISDICTION_NOT_SUPPORTED,
+            compliance_codes::COMPLIANCE_INVALID_DOCUMENT_TYPE,
+            compliance_codes::COMPLIANCE_DATA_RETENTION_EXPIRED,
+        ];
+        let len = codes.len();
+        codes.sort();
+        codes.dedup();
+        assert_eq!(
+            codes.len(),
+            len,
+            "duplicate compliance error codes detected"
+        );
+    }
+}