diff --git a/src/components/Headline/Headline.svelte b/src/components/Headline/Headline.svelte
index 73e45097..447f5b78 100644
--- a/src/components/Headline/Headline.svelte
+++ b/src/components/Headline/Headline.svelte
@@ -108,7 +108,7 @@
         {/if}
         {#if typeof hed === 'string'}
           <h1 class={hedClass}>
-            <Markdown source={hed} parseInline />
+            <Markdown source={hed} inline />
           </h1>
         {:else if hed}
           <!-- Headline snippet -->
diff --git a/src/components/InfoBox/InfoBox.svelte b/src/components/InfoBox/InfoBox.svelte
index 1aa5d1fe..d3479636 100644
--- a/src/components/InfoBox/InfoBox.svelte
+++ b/src/components/InfoBox/InfoBox.svelte
@@ -83,7 +83,7 @@
       </div>
     {:else}
       <div class="body">
-        <Markdown source={text} />
+        <Markdown source={text || ''} />
       </div>
     {/if}
 
diff --git a/src/docs/utils/css-to-js/index.d.ts b/src/docs/utils/css-to-js/index.d.ts
index 6f1f4a47..9f5673f5 100644
--- a/src/docs/utils/css-to-js/index.d.ts
+++ b/src/docs/utils/css-to-js/index.d.ts
@@ -1 +1,2 @@
-export function convert(input: any, ...args: any[]): any;
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export function convert(input: any, ...args: any[]): Record<string, string>;
diff --git a/src/docs/utils/parseCss.js b/src/docs/utils/parseCss.ts
similarity index 90%
rename from src/docs/utils/parseCss.js
rename to src/docs/utils/parseCss.ts
index e65de5e8..2451462a 100644
--- a/src/docs/utils/parseCss.js
+++ b/src/docs/utils/parseCss.ts
@@ -16,9 +16,8 @@ export const cssStringToTableArray = (cssString = '', withInclude = false) => {
         )};`;
       })
       .join('\n');
-    return withInclude ?
-        [className, className, properties]
-      : [className, properties];
+    if (withInclude) return [className, className, properties];
+    return [className, properties];
   });
 };
 
@@ -35,7 +34,7 @@ export const extractCssColourVariables = (cssString = '') => {
   const cssVariables = [...cssString.matchAll(variableRegexp)].map(
     ([_, g1, g2]) => [g2, g1]
   );
-  const colours = {};
+  const colours: Record<string, string[]> = {};
   for (const variable of cssVariables) {
     const [colour, css] = variable;
     if (colours[colour]) {
diff --git a/src/docs/utils/withParams.js b/src/docs/utils/withParams.js
deleted file mode 100644
index d92af00a..00000000
--- a/src/docs/utils/withParams.js
+++ /dev/null
@@ -1,46 +0,0 @@
-/**
- * Use custom source code in the "Show code" pull down.
- * @param {object} source Source code object, where key is the language of the source code and value is the code string.
- * @param {object} otherOptions Other props object options, allowing chaining with other methods like withStoryDocs
- * @returns props object including parameters
- */
-export const withSource = (source, otherOptions = {}) => {
-  const language = Object.keys(source)[0];
-  const code = source[language];
-  const docs = {
-    ...otherOptions?.parameters?.docs,
-    source: { code, language },
-  };
-  const parameters = { docs };
-  return { parameters };
-};
-
-/**
- * Add custom documentation to a story.
- * @param {string} storyDocs Markdown string of docs
- * @param {object} otherOptions Other props object options, allowing chaining with other methods like withSource
- * @returns props object including parameters
- */
-export const withStoryDocs = (storyDocs, otherOptions = {}) => {
-  const docs = {
-    ...otherOptions?.parameters?.docs,
-    description: { story: storyDocs },
-  };
-  const parameters = { docs };
-  return { parameters };
-};
-
-/**
- * Add custom documentation to the top of the component docs page.
- * @param {string} componentDocs Markdown string of docs
- * @param {object} otherOptions Other props object options, allowing chaining with other methods like withSource
- * @returns props object including parameters
- */
-export const withComponentDocs = (componentDocs, otherOptions = {}) => {
-  const docs = {
-    ...otherOptions?.parameters?.docs,
-    description: { component: componentDocs },
-  };
-  const parameters = { docs };
-  return { parameters };
-};