diff --git a/packages/backend-common/src/reading/AzureUrlReader.ts b/packages/backend-common/src/reading/AzureUrlReader.ts
index 8e6e6a75df..79058c79a9 100644
--- a/packages/backend-common/src/reading/AzureUrlReader.ts
+++ b/packages/backend-common/src/reading/AzureUrlReader.ts
@@ -17,7 +17,7 @@
 import fetch from 'cross-fetch';
 import { Config } from '@backstage/config';
 import { NotFoundError } from '../errors';
-import { ReaderFactory, UrlReader } from './types';
+import { ReaderFactory, ReadTreeResponse, UrlReader } from './types';
 
 type Options = {
   // TODO: added here for future support, but we only allow dev.azure.com for now
@@ -86,6 +86,10 @@ export class AzureUrlReader implements UrlReader {
     throw new Error(message);
   }
 
+  readTree(): Promise<ReadTreeResponse> {
+    throw new Error('AzureUrlReader does not implement readTree');
+  }
+
   // Converts
   // from: https://dev.azure.com/{organization}/{project}/_git/reponame?path={path}&version=GB{commitOrBranch}&_a=contents
   // to:   https://dev.azure.com/{organization}/{project}/_apis/git/repositories/reponame/items?path={path}&version={commitOrBranch}
diff --git a/packages/backend-common/src/reading/BitbucketUrlReader.ts b/packages/backend-common/src/reading/BitbucketUrlReader.ts
index 348426fd34..b2fb9fa309 100644
--- a/packages/backend-common/src/reading/BitbucketUrlReader.ts
+++ b/packages/backend-common/src/reading/BitbucketUrlReader.ts
@@ -18,7 +18,7 @@ import { Config } from '@backstage/config';
 import parseGitUri from 'git-url-parse';
 import fetch from 'cross-fetch';
 import { NotFoundError } from '../errors';
-import { ReaderFactory, UrlReader } from './types';
+import { ReaderFactory, ReadTreeResponse, UrlReader } from './types';
 
 const DEFAULT_BASE_URL = 'https://api.bitbucket.org/2.0';
 
@@ -209,6 +209,10 @@ export class BitbucketUrlReader implements UrlReader {
     throw new Error(message);
   }
 
+  readTree(): Promise<ReadTreeResponse> {
+    throw new Error('BitbucketUrlReader does not implement readTree');
+  }
+
   toString() {
     const { host, token, username, appPassword } = this.config;
     let authed = Boolean(token);
diff --git a/packages/backend-common/src/reading/FetchUrlReader.ts b/packages/backend-common/src/reading/FetchUrlReader.ts
index d2e5c45620..1d1784590c 100644
--- a/packages/backend-common/src/reading/FetchUrlReader.ts
+++ b/packages/backend-common/src/reading/FetchUrlReader.ts
@@ -16,7 +16,7 @@
 
 import fetch from 'cross-fetch';
 import { NotFoundError } from '../errors';
-import { UrlReader } from './types';
+import { ReadTreeResponse, UrlReader } from './types';
 
 /**
  * A UrlReader that does a plain fetch of the URL.
@@ -41,6 +41,10 @@ export class FetchUrlReader implements UrlReader {
     throw new Error(message);
   }
 
+  readTree(): Promise<ReadTreeResponse> {
+    throw new Error('FetchUrlReader does not implement readTree');
+  }
+
   toString() {
     return 'fetch{}';
   }
diff --git a/packages/backend-common/src/reading/GitlabUrlReader.ts b/packages/backend-common/src/reading/GitlabUrlReader.ts
index 378e76fb61..c621e41338 100644
--- a/packages/backend-common/src/reading/GitlabUrlReader.ts
+++ b/packages/backend-common/src/reading/GitlabUrlReader.ts
@@ -17,7 +17,7 @@
 import fetch from 'cross-fetch';
 import { Config } from '@backstage/config';
 import { NotFoundError } from '../errors';
-import { ReaderFactory, UrlReader } from './types';
+import { ReaderFactory, ReadTreeResponse, UrlReader } from './types';
 
 type Options = {
   host: string;
@@ -87,6 +87,10 @@ export class GitlabUrlReader implements UrlReader {
     throw new Error(message);
   }
 
+  readTree(): Promise<ReadTreeResponse> {
+    throw new Error('GitlabUrlReader does not implement readTree');
+  }
+
   // Converts
   // from: https://gitlab.example.com/a/b/blob/master/c.yaml
   // to:   https://gitlab.example.com/a/b/raw/master/c.yaml
diff --git a/packages/backend-common/src/reading/UrlReaderPredicateMux.ts b/packages/backend-common/src/reading/UrlReaderPredicateMux.ts
index 9b0566106a..9a81fdc9ab 100644
--- a/packages/backend-common/src/reading/UrlReaderPredicateMux.ts
+++ b/packages/backend-common/src/reading/UrlReaderPredicateMux.ts
@@ -66,19 +66,12 @@ export class UrlReaderPredicateMux implements UrlReader {
 
     for (const { predicate, reader } of this.readers) {
       if (predicate(parsed)) {
-        if (reader.readTree) return reader.readTree(repoUrl, options);
-        throw new Error(
-          `Trying to call readTree on UrlReader which does not support the feature.`,
-        );
+        return reader.readTree(repoUrl, options);
       }
     }
 
     if (this.fallback) {
-      if (this.fallback.readTree)
-        return this.fallback.readTree(repoUrl, options);
-      throw new Error(
-        `Trying to call readTree on UrlReader which does not support the feature.`,
-      );
+      return this.fallback.readTree(repoUrl, options);
     }
 
     throw new Error(`No reader found that could handle '${repoUrl}'`);
diff --git a/packages/backend-common/src/reading/types.ts b/packages/backend-common/src/reading/types.ts
index c7e5915401..101502fed7 100644
--- a/packages/backend-common/src/reading/types.ts
+++ b/packages/backend-common/src/reading/types.ts
@@ -28,7 +28,7 @@ export type ReadTreeOptions = {
  */
 export type UrlReader = {
   read(url: string): Promise<Buffer>;
-  readTree?(url: string, options?: ReadTreeOptions): Promise<ReadTreeResponse>;
+  readTree(url: string, options?: ReadTreeOptions): Promise<ReadTreeResponse>;
 };
 
 export type UrlReaderPredicateTuple = {
diff --git a/plugins/catalog-backend/src/ingestion/processors/CodeOwnersProcessor.test.ts b/plugins/catalog-backend/src/ingestion/processors/CodeOwnersProcessor.test.ts
index e4ddb249d6..dfb470fa21 100644
--- a/plugins/catalog-backend/src/ingestion/processors/CodeOwnersProcessor.test.ts
+++ b/plugins/catalog-backend/src/ingestion/processors/CodeOwnersProcessor.test.ts
@@ -157,14 +157,14 @@ describe('CodeOwnersProcessor', () => {
       const read = jest
         .fn()
         .mockResolvedValue(mockReadResult({ data: ownersText }));
-      const reader = { read };
+      const reader = { read, readTree: jest.fn() };
       const result = await findRawCodeOwners(mockLocation(), reader);
       expect(result).toEqual(ownersText);
     });
 
     it('should raise error when no codeowner', async () => {
       const read = jest.fn().mockRejectedValue(mockReadResult());
-      const reader = { read };
+      const reader = { read, readTree: jest.fn() };
 
       await expect(
         findRawCodeOwners(mockLocation(), reader),
@@ -178,7 +178,7 @@ describe('CodeOwnersProcessor', () => {
         .mockImplementationOnce(() => mockReadResult({ error: 'foo' }))
         .mockImplementationOnce(() => mockReadResult({ error: 'bar' }))
         .mockResolvedValue(mockReadResult({ data: ownersText }));
-      const reader = { read };
+      const reader = { read, readTree: jest.fn() };
 
       const result = await findRawCodeOwners(mockLocation(), reader);
 
@@ -197,7 +197,7 @@ describe('CodeOwnersProcessor', () => {
       const read = jest
         .fn()
         .mockResolvedValue(mockReadResult({ data: mockCodeOwnersText() }));
-      const reader = { read };
+      const reader = { read, readTree: jest.fn() };
 
       const owner = await resolveCodeOwner(mockLocation(), reader);
       expect(owner).toBe('backstage-core');
@@ -207,7 +207,7 @@ describe('CodeOwnersProcessor', () => {
       const read = jest
         .fn()
         .mockImplementation(() => mockReadResult({ error: 'error: foo' }));
-      const reader = { read };
+      const reader = { read, readTree: jest.fn() };
 
       await expect(
         resolveCodeOwner(mockLocation(), reader),
@@ -221,7 +221,7 @@ describe('CodeOwnersProcessor', () => {
       const read = jest
         .fn()
         .mockResolvedValue(mockReadResult({ data: mockCodeOwnersText() }));
-      const reader = { read };
+      const reader = { read, readTree: jest.fn() };
       const processor = new CodeOwnersProcessor({ reader });
 
       return { entity, processor, read };
diff --git a/plugins/catalog-backend/src/ingestion/processors/PlaceholderProcessor.test.ts b/plugins/catalog-backend/src/ingestion/processors/PlaceholderProcessor.test.ts
index 48cd2dae01..5a3511af6d 100644
--- a/plugins/catalog-backend/src/ingestion/processors/PlaceholderProcessor.test.ts
+++ b/plugins/catalog-backend/src/ingestion/processors/PlaceholderProcessor.test.ts
@@ -27,7 +27,7 @@ import {
 
 describe('PlaceholderProcessor', () => {
   const read: jest.MockedFunction<ResolverRead> = jest.fn();
-  const reader: UrlReader = { read };
+  const reader: UrlReader = { read, readTree: jest.fn() };
 
   beforeEach(() => {
     jest.resetAllMocks();
diff --git a/plugins/catalog-backend/src/service/CatalogBuilder.test.ts b/plugins/catalog-backend/src/service/CatalogBuilder.test.ts
index 45d92e6555..ee7c6f2246 100644
--- a/plugins/catalog-backend/src/service/CatalogBuilder.test.ts
+++ b/plugins/catalog-backend/src/service/CatalogBuilder.test.ts
@@ -40,7 +40,10 @@ const dummyEntityYaml = yaml.stringify(dummyEntity);
 
 describe('CatalogBuilder', () => {
   let db: Knex<any, unknown[]>;
-  const reader: jest.Mocked<UrlReader> = { read: jest.fn() };
+  const reader: jest.Mocked<UrlReader> = {
+    read: jest.fn(),
+    readTree: jest.fn(),
+  };
   const env: CatalogEnvironment = {
     logger: getVoidLogger(),
     database: { getClient: async () => db },
diff --git a/plugins/techdocs-backend/src/helpers.ts b/plugins/techdocs-backend/src/helpers.ts
index 97b087558f..901aea533a 100644
--- a/plugins/techdocs-backend/src/helpers.ts
+++ b/plugins/techdocs-backend/src/helpers.ts
@@ -179,13 +179,7 @@ export const getDocFilesFromRepository = async (
     entity,
   );
 
-  if (reader.readTree) {
-    const response = await reader.readTree(target);
+  const response = await reader.readTree(target);
 
-    return response.dir();
-  }
-
-  throw new Error(
-    `No readTree method available on the UrlReader for ${target}`,
-  );
+  return await response.dir();
 };