diff --git a/client/src/webview/views/diagnostics/errors.ts b/client/src/webview/views/diagnostics/errors.ts
index 037d542..ff4758b 100644
--- a/client/src/webview/views/diagnostics/errors.ts
+++ b/client/src/webview/views/diagnostics/errors.ts
@@ -30,13 +30,11 @@ export function renderErrors(errors: LJError[], expandedErrors: Set<number>): st
 
 const errorContentRenderers: Partial<Record<LJError['type'], (error: LJError) => string>> = {
     'refinement-error': (e: RefinementError) => /*html*/`
-        ${e.customMessage ? renderSection('Message', e.customMessage) : ''}
         ${renderCustomSection('Expected', renderDerivationNode(e, e.expected, 'expected'))}
         ${renderCustomSection('Found', renderDerivationNode(e, e.found, 'found'))}
         ${e.counterexample ? renderSection('Counterexample', e.counterexample) : ''}
     `,
     'state-refinement-error': (e: StateRefinementError) => /*html*/`
-        ${e.customMessage ? renderSection('Message', e.customMessage) : ''}
         ${renderSection('Expected', e.expected)}
         ${renderSection('Found', e.found)}
     `,
@@ -58,8 +56,9 @@ const errorContentRenderers: Partial<Record<LJError['type'], (error: LJError) =>
 };
 
 export function renderError(error: LJError, errorIndex: number, isExpanded: boolean): string {
-    const header = renderDiagnosticHeader(error);
-    const content = errorContentRenderers[error.type]?.(error) ?? '';
+    const message = error.type === 'refinement-error' || error.type === 'state-refinement-error' ? error.customMessage : error.message;
+    const header = renderDiagnosticHeader(error.title, message || '');
+    const content = errorContentRenderers[error.type]?.(error) || '';
     const location = renderLocation(error);
     const extra = renderExtra(error, errorIndex, isExpanded);
     return /*html*/`${header}${content}${location}${extra}`;
@@ -77,4 +76,4 @@ function renderExtra(error: LJError, errorIndex: number, isExpanded: boolean): s
         extra += renderTranslationTable((error as any).translationTable as TranslationTable);
     }
     return extra ? isExpanded ? /*html*/`${button}<div class="extra-content">${extra}</div>` : button : "";
-}
\ No newline at end of file
+}
diff --git a/client/src/webview/views/diagnostics/warnings.ts b/client/src/webview/views/diagnostics/warnings.ts
index dde140e..d32178c 100644
--- a/client/src/webview/views/diagnostics/warnings.ts
+++ b/client/src/webview/views/diagnostics/warnings.ts
@@ -24,7 +24,7 @@ const warningContentRenderers: Partial<Record<LJWarning['type'], (warning: LJWar
 };
 
 export function renderWarning(warning: LJWarning): string {
-    const header = renderDiagnosticHeader(warning);
+    const header = renderDiagnosticHeader(warning.title, warning.message);
     const content = warningContentRenderers[warning.type]?.(warning) ?? '';
     const location = renderLocation(warning);
     return /*html*/`${header}${content}${location}`;
diff --git a/client/src/webview/views/sections.ts b/client/src/webview/views/sections.ts
index dc9c61a..04d30de 100644
--- a/client/src/webview/views/sections.ts
+++ b/client/src/webview/views/sections.ts
@@ -20,8 +20,8 @@ export const renderToggleSection = (title: string, targetId: string, isExpanded:
     </button>
     `;
 
-export const renderDiagnosticHeader = (diagnostic: LJDiagnostic): string => /*html*/
-    `<h3>${diagnostic.title}</h3><div class="diagnostic-header"><p>${diagnostic.message}</p></div>`;
+export const renderDiagnosticHeader = (title: string, message: string): string => /*html*/
+    `<h3>${title}</h3><div class="diagnostic-header"><p>${message}</p></div>`;
 
 export const renderLocation = (diagnostic: LJDiagnostic): string => {
     if (!diagnostic.position || !diagnostic.file) return "";