> You are reading the Docusign Developer Documentation. For clean Markdown of any page, append .md to the page URL. > > Documentation indexes by section: > - APIs and SDKs: https://docusign.docs.buildwithfern.com/docs/llms.txt > - Platform 101: https://docusign.docs.buildwithfern.com/platform/llms.txt > - Extension Apps: https://docusign.docs.buildwithfern.com/extension-apps/llms.txt > - Docusign CLI: https://docusign.docs.buildwithfern.com/docusign-cli/llms.txt > > Authentication (OAuth, JWT Grant, M2M): https://docusign.docs.buildwithfern.com/platform/auth > Webhooks and Connect: https://docusign.docs.buildwithfern.com/platform/webhooks > > OpenAPI specifications: https://docusign.docs.buildwithfern.com/openapi.json > MCP server: https://docusign.docs.buildwithfern.com/_mcp/server # Extension Apps ## Docs - [Extension apps 101](https://developers.docusign.com/extension-apps/extension-apps-101.md): Learn what extension apps are and how you can use them to extend your Docusign workflows. - [Extension app use cases](https://developers.docusign.com/extension-apps/extension-apps-101/use-cases.md): See how extension apps can help you simplify document preparation, signing, and post-signing tasks. - [How extension apps work](https://developers.docusign.com/extension-apps/extension-apps-101/how-extension-apps-work.md): See an overview of extension app elements and how they fit together to extend Docusign functionality. - [What's inside an extension app registration](https://developers.docusign.com/extension-apps/extension-apps-101/inside-an-extension-app.md): Learn the basics about the different pieces of an extension app registration - [Supported extensions](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions.md): See a list of the supported extensions for Docusign extension apps. - [Connected fields extension overview](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/connected-fields.md): Get an overview of an extension that performs real-time custom data verification against a system of record. - [Data IO extension overview](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/data-io.md): Lean how the data IO extension works, where it is used, and how it executes. - [Define related objects in a data model](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/data-io/related-objects.md): Learn how to define related objects in the data model for a data IO extension app. - [Data model](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/data-model.md): Learn about the data model that Docusign extension apps use. - [File input cloud storage extension overview](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-input-cloud-storage.md): Import agreements from a cloud storage service to the Docusign Navigator smart repository. - [File input system of record extension overview (beta)](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-input-system-of-record.md) - [File output cloud storage extension overview](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-output-cloud-storage.md): Learn about how files generated from Docusign workflows can be written to cloud storage in real time. - [File output system of record extension overview (beta)](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-output-system-of-record.md): Learn about how files generated from Docusign workflows can be written to a system of record in real time. - [Identify destination records (beta)](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-output-system-of-record/identify-destination-records.md): Review the options for identifying records to which files will be written. - [Identify the file source (beta)](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-output-system-of-record/identify-file-source.md): Review the options for the source of files to write to a system of record. - [Workflow configuration for file output scenarios (beta)](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-output-system-of-record/workflow-configuration.md): Review workflow configuration options for various file output scenarios. - [Extensions and actions (beta)](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-output-system-of-record/extensions-and-actions.md): Review the extensions and actions associated with file output to system of record. - [Plan an implementation (beta)](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-output-system-of-record/plan-implementation.md): Learn about important considerations when planning a file output to system of record implementation. - [File output tabular format extension overview](https://developers.docusign.com/extension-apps/extension-apps-101/supported-extensions/file-output-tabular-format.md) - [How extension apps differ from API integrations](https://developers.docusign.com/extension-apps/extension-apps-101/extension-app-vs-api-integrations.md): Learn about the differences between extension apps and API integrations. - [App Center](https://developers.docusign.com/extension-apps/extension-apps-101/app-center.md): Learn how to publish your extension apps to the App Center and make them available for Docusign users to find, purchase, and use. - [Choosing private distribution instead of public](https://developers.docusign.com/extension-apps/extension-apps-101/choosing-private-distribution.md): Learn about the difference between private extension apps and public extension apps. - [Globalization](https://developers.docusign.com/extension-apps/extension-apps-101/globalization.md): Learn how to prepare your extension app for distribution in different regions. - [Extension app concepts](https://developers.docusign.com/extension-apps/extension-apps-101/concepts.md): Learn extension apps concepts. - [Extension app manifest](https://developers.docusign.com/extension-apps/extension-apps-101/concepts/extension-app-manifest.md): Learn what an extension app manifest is, what it does, and how it is organized. - [Actions](https://developers.docusign.com/extension-apps/extension-apps-101/concepts/actions.md): Learn about the actions that you can trigger in an extension app. - [Capabilities](https://developers.docusign.com/extension-apps/extension-apps-101/concepts/capabilities.md): Learn about optional extension app actions that enhance an extension's base functionality. - [Connections](https://developers.docusign.com/extension-apps/extension-apps-101/concepts/connections.md): Learn about defining a connection for your extension app manifest file. - [Extensions and extension points](https://developers.docusign.com/extension-apps/extension-apps-101/concepts/extensions-and-extension-points.md): Learn what extensions are and when their actions are triggered. - [Use extensions in Workflow Builder workflows](https://developers.docusign.com/extension-apps/workflows.md): Learn how Workflow Builder API workflows enable you to build and digitize agreement processes with Docusign and Partner services in an easy no-code experience. - [Developer Console overview](https://developers.docusign.com/extension-apps/developer-console-overview.md): Learn about Developer Console features that enable you to create and manage extension apps. - [Build an extension app](https://developers.docusign.com/extension-apps/build-an-extension-app.md): Get an overview of the steps to build an extension app. - [Example extension app use cases](https://developers.docusign.com/extension-apps/build-an-extension-app/example-use-case.md): Explore example extension app use cases and learn how extension apps can help streamline your workflow. - [Set up your IT infrastructure](https://developers.docusign.com/extension-apps/build-an-extension-app/it-infrastructure.md): Learn about setup information for the types of services to which extension apps will send requests. - [API proxy](https://developers.docusign.com/extension-apps/build-an-extension-app/it-infrastructure/api-proxy.md): Get an overview of a component that serves as an intermediary between a Docusign extension app and the third-party API service to which it sends requests. - [Authorization](https://developers.docusign.com/extension-apps/build-an-extension-app/it-infrastructure/authorization.md): Get an overview of the process by which an extension app obtains authorization to access resources in a third-party service. - [Network configuration](https://developers.docusign.com/extension-apps/build-an-extension-app/it-infrastructure/network-configuration.md): Learn about network setup required to ensure that Docusign can communicate successfully with your platform. - [Register an extension app](https://developers.docusign.com/extension-apps/build-an-extension-app/register.md): Learn how to supply Docusign with technical and descriptive information about an extension app. - [Use a form to register an extension app](https://developers.docusign.com/extension-apps/build-an-extension-app/register/use-form.md): Learn how to register an extension app using a guided form-based UI. - [Update integration details](https://developers.docusign.com/extension-apps/build-an-extension-app/register/use-form/integration-details.md): Learn how to define extension app settings required to obtain authorization and connect to endpoints in the external API service. - [Update App Center listing](https://developers.docusign.com/extension-apps/build-an-extension-app/register/use-form/app-center-listing.md): Learn how to define the text and images that appear in an extension app listing in the Docusign App Center. - [Use a manifest file to register an extension app](https://developers.docusign.com/extension-apps/build-an-extension-app/register/use-manifest.md): This guide describes the steps for registering an extension app by building a JSON app manifest file. - [Test an extension app](https://developers.docusign.com/extension-apps/build-an-extension-app/test.md): Learn how to verify that your extension app has been configured correctly. - [Integration tests](https://developers.docusign.com/extension-apps/build-an-extension-app/test/integration-tests.md): Learn how to verify that an extension app can obtain authorization, send requests to a third-party API, and process the responses. - [Functional tests](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests.md): Learn how to verify that an extension app works as expected when invoked from a Docusign envelope or workflow. - [Connected fields extension envelope test](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests/connected-fields-envelope.md): Learn how to set up and execute a functional test that invokes a connected fields extension from an eSignature envelope. - [Data IO extension workflow test](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests/data-io-workflow.md): Learn how to test a data IO extension in a workflow. - [Data verification extension envelope test](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests/data-verification-envelope.md): Learn how to test a data verification extension in an envelope. - [File input cloud storage extension Agreement Manager test](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests/file-input-cloud-storage-agreement-manager.md): Test a file input from cloud storage extension app with Docusign Agreement Manager. - [File output cloud storage extension workflow test](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests/file-output-cloud-storage-workflow.md): Learn how to test a file output cloud storage extension from a Maestro workflow. - [File output system of record test: An event triggers the workflow (beta)](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests/file-output-system-of-record-event-triggers-workflow.md): Learn how to test a file output system of record extension from a Maestro workflow that that's triggered by an event. - [File output system of record test: Workflow step creates envelopes (beta)](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests/file-output-system-of-record-workflow-step-creates-envelopes.md): Learn how to test a file output system of record extension from a Maestro workflow in which envelopes are created by a workflow step. - [File output tabular format extension workflow test](https://developers.docusign.com/extension-apps/build-an-extension-app/test/functional-tests/file-output-tabular-format-workflow.md): Learn how to test a file output tabular format extension from a Maestro workflow. - [App Center preview](https://developers.docusign.com/extension-apps/build-an-extension-app/test/app-center-preview.md): Learn how to check details that will appear when App Center users display your extension app's information. - [Update an extension app registration](https://developers.docusign.com/extension-apps/build-an-extension-app/update-registration.md): Learn how to update an extension app's technical or descriptive information that is registered with Docusign. - [Use a form to update a registration](https://developers.docusign.com/extension-apps/build-an-extension-app/update-registration/use-form.md): Learn how to update an extension app registration using a form. - [Use a manifest file to update a registration](https://developers.docusign.com/extension-apps/build-an-extension-app/update-registration/use-manifest.md): This guide describes the steps for updating an extension app registration by editing a JSON app manifest file. - [Delete an extension app](https://developers.docusign.com/extension-apps/build-an-extension-app/delete.md): Describes conditions and steps to deleting an extension app. - [Publish an extension app to the Docusign App Center](https://developers.docusign.com/extension-apps/build-an-extension-app/publish.md): Learn how to publish your extension app to the Docusign App Center - [App Center publishing guidelines](https://developers.docusign.com/extension-apps/build-an-extension-app/publish/guidelines.md): See the guidelines and review criteria for publishing your extension app to the Docusign App Center. - [Monitor extension app usage](https://developers.docusign.com/extension-apps/build-an-extension-app/monitor-usage.md): See how many Docusign accounts have installed your extension app. - [Extension app versioning](https://developers.docusign.com/extension-apps/build-an-extension-app/versioning.md): Learn how to update your extension app by creating new versions, and find out how new versions are distributed to your customers. - [Extension app status and distribution](https://developers.docusign.com/extension-apps/build-an-extension-app/status.md): Learn about two types of status associated with extension apps. - [Extension app best practices](https://developers.docusign.com/extension-apps/best-practices.md): Get guidance and best practices for building your extension app. - [Connection behaviors and best practices](https://developers.docusign.com/extension-apps/best-practices/connection-behaviors-and-best-practices.md): Get information about extension app connection behaviors and guidance to help ensure that connections function correctly. - [Troubleshooting](https://developers.docusign.com/extension-apps/troubleshooting.md): Get tips for troubleshooting extension app errors. - [Troubleshooting for connected fields extensions](https://developers.docusign.com/extension-apps/troubleshooting/connected-fields.md): Get troubleshooting guidance for issues that may arise when working with connected fields extensions. - [Review extension app logs](https://developers.docusign.com/extension-apps/troubleshooting/review-logs.md): Find out how to access extension app logs in the Developer Console. - [Support resources and FAQs](https://developers.docusign.com/extension-apps/support-faqs.md): Get answers to the most common questions about extension apps and discover how to get developer support. - [Extension app glossary](https://developers.docusign.com/extension-apps/glossary.md): Defines common terms used throughout the Docusign extension apps documentation. - [Extension app reference](https://developers.docusign.com/extension-apps/extension-app-reference.md) - [App manifest reference](https://developers.docusign.com/extension-apps/extension-app-reference/app-manifest-reference.md): Reference for the app manifest schema. - [Connection schema](https://developers.docusign.com/extension-apps/extension-app-reference/app-manifest-reference/connection.md): Learn about the schema for the connection object in your extension app manifest. - [Extension schema](https://developers.docusign.com/extension-apps/extension-app-reference/app-manifest-reference/extension.md): Learn about the extension object schema for your extension app manifest. - [Action schema](https://developers.docusign.com/extension-apps/extension-app-reference/app-manifest-reference/action.md): Learn about the action object structure for your extension app manifest schema. - [Troubleshooting manifest errors](https://developers.docusign.com/extension-apps/extension-app-reference/app-manifest-reference/troubleshooting-manifest-errors.md): Learn about common manifest errors and how to resolve them. - [Extension contracts](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts.md): Reference for Docusign extension contracts. - [Connected fields extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/connected-fields.md): Get the details for connected fields actions, the request formats, and the response formats. - [Data IO extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/data-io.md): Learn how to implement the Docusign data IO extension. - [Custom query language reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/custom-query-language.md): Learn about Docusign's custom query language for the data I/O extension. - [Bank account owner verification extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/bank-account-owner-verification.md): Reference information for the bank account owner verification extension. - [Bank account verification extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/bank-account-verification.md): Learn about the requirements to implement the bank account verification extension. - [Business FEIN verification extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/business-fein-verification.md): Learn how to use the business FEIN verification extension. - [Email address verification extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/email-address-verification.md): Learn how to implement the email address verification extension. - [Phone verification extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/phone-verification.md): Learn how to use the phone verification extension. - [Postal address verification extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/postal-address-verification.md): Learn about the requirements to implement the postal address verification extension. - [SSN verification extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/ssn-verification.md): Learn how to use the SSN verification extension. - [File input cloud storage extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/file-input-cloud-storage.md): Get technical details about file input cloud storage extension requests and responses. - [File input system of record extension contract reference (beta)](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/file-input-system-of-record.md) - [File output cloud storage extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/file-output-cloud-storage.md): Get technical details about file output cloud storage extension requests and responses. - [File output system of record extension contract reference (beta)](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/file-output-system-of-record.md): Get technical details about file output system of record extension requests and responses. - [File output tabular format extension contract reference](https://developers.docusign.com/extension-apps/extension-app-reference/extension-contracts/file-output-tabular-format.md): Get technical details about file output tabular format extension requests and responses. > **Note:** This page contains both a page directory (above) and the landing page content (below). The page directory is generated for agent use and does not appear on the landing page. > You are reading the Docusign Developer Documentation. For clean Markdown of any page, append .md to the page URL. > > Documentation indexes by section: > - APIs and SDKs: https://docusign.docs.buildwithfern.com/docs/llms.txt > - Platform 101: https://docusign.docs.buildwithfern.com/platform/llms.txt > - Extension Apps: https://docusign.docs.buildwithfern.com/extension-apps/llms.txt > - Docusign CLI: https://docusign.docs.buildwithfern.com/docusign-cli/llms.txt > > Authentication (OAuth, JWT Grant, M2M): https://docusign.docs.buildwithfern.com/platform/auth > Webhooks and Connect: https://docusign.docs.buildwithfern.com/platform/webhooks > > OpenAPI specifications: https://docusign.docs.buildwithfern.com/openapi.json > MCP server: https://docusign.docs.buildwithfern.com/_mcp/server # Extension apps overview > Extend Docusign with third-party capabilities that you design to be activated at specific points in Docusign agreements and workflows. Extension apps enable you to build custom external functionality into Docusign and publish your solutions in the App Center, giving all customers, or just customers you specify, easy, automated ways to enhance their Docusign experience and use your app in Workflow Builder workflows. ## Features #### Extend Docusign your way Enhance Docusign with functions from external APIs, added at predefined points in Docusign workflows. #### Create apps quickly Use the Developer Console to seamlessly register your app and test it with our platform. #### Publish your apps Publish your apps to the App Center to reach a market of over 1.6 million Docusign customers; or, if you wish, distribute them privately to individual customers or to your own organization. ## Places to start * [Discover extension apps](/extension-apps/extension-apps-101) * [Register within the Developer Console](/extension-apps/developer-console-overview) * [Reference the App Manifest documentation](/extension-apps/extension-app-reference/app-manifest-reference) * [Distribute to the App center](/extension-apps/extension-apps-101/app-center) * [Learn your options for public and private distribution](/extension-apps/extension-apps-101/choosing-private-distribution) * [Extension Apps course on Docusign University](https://dsudevelopers.docusign.com/path/docusign-extension-apps) ## Discover more * [Get started building your own extension apps](/extension-apps/build-an-extension-app) * [Review extension app use cases](/extension-apps/build-an-extension-app/example-use-case) * [Learn how to build extension apps for the App Center through a Docusign University course](https://dsudevelopers.docusign.com/build-extension-apps-for-the-docusign-app-center) * [See how to integrate external features using extension apps](https://bcove.video/4itWmK8)