diff --git a/core/connectors/sdk/src/lib.rs b/core/connectors/sdk/src/lib.rs
index 2289aa9503..aee7d8c78b 100644
--- a/core/connectors/sdk/src/lib.rs
+++ b/core/connectors/sdk/src/lib.rs
@@ -425,4 +425,20 @@ pub enum Error {
     /// failures so that circuit breakers are not tripped by bad data.
     #[error("Permanent HTTP error: {0}")]
     PermanentHttpError(String),
+    /// The source schema could not be mapped to the destination schema.
+    /// Indicates a table definition or configuration problem
+    #[error("Schema mismatch: {0}")]
+    SchemaMismatch(String),
+    /// An I/O failure while writing data (e.g. Parquet serialization, file
+    /// writer close). Distinct from record-level validation errors.
+    #[error("Write failure: {0}")]
+    WriteFailure(String),
+    /// In-memory transaction preparation failed (e.g. invalid partition spec,
+    /// schema validation). These failures are deterministic and not retryable.
+    #[error("Transaction apply error: {0}")]
+    TransactionApplyError(String),
+    /// A catalog commit failed over the network (e.g. REST catalog I/O,
+    /// conflict). Transient failures may be retried.
+    #[error("Catalog commit error: {0}")]
+    CatalogCommitError(String),
 }
diff --git a/core/connectors/sinks/iceberg_sink/src/router/mod.rs b/core/connectors/sinks/iceberg_sink/src/router/mod.rs
index 8e60beedfc..ed5ca2bb3d 100644
--- a/core/connectors/sinks/iceberg_sink/src/router/mod.rs
+++ b/core/connectors/sinks/iceberg_sink/src/router/mod.rs
@@ -178,7 +178,7 @@ async fn write_data(
                 table.metadata().uuid(),
                 err
             );
-            Error::InvalidRecord
+            Error::SchemaMismatch(err.to_string())
         })?,
     ))
     .build(cursor)
@@ -197,13 +197,13 @@ async fn write_data(
         })?;
         writer.write(batch_data).await.map_err(|err| {
             error!("Error while writing record batch: {}", err);
-            Error::InvalidRecord
+            Error::WriteFailure(err.to_string())
         })?;
     }
 
     let data_files = writer.close().await.map_err(|err| {
         error!("Error while writing data records to Parquet file: {}", err);
-        Error::InvalidRecord
+        Error::WriteFailure(err.to_string())
     })?;
 
     let table_commit = Transaction::new(table);
@@ -216,7 +216,7 @@ async fn write_data(
             table.metadata().uuid(),
             err
         );
-        Error::InvalidRecord
+        Error::TransactionApplyError(err.to_string())
     })?;
 
     let _table = tx.commit(catalog).await.map_err(|err| {
@@ -225,7 +225,7 @@ async fn write_data(
             table.metadata().uuid(),
             err
         );
-        Error::InvalidRecord
+        Error::CatalogCommitError(err.to_string())
     })?;
     Ok(())
 }