What is a Commenting SDK?

A commenting SDK lets you easily add in-app commenting, like in Figma or Google Docs, to your product. With just a few lines of code, you can let users start threaded chats on top of text, designs, video frames, or data points while skipping months of backend effort. In this guide, we walk through how a commenting SDK works, what to look for, and why it is now a favorite shortcut for product teams that want collaborative features.

TLDR:

• A commenting SDK handles all the hard real-time infrastructure + UI components so you can roll out in-app async comments in days.

• Features include text highlights, canvas pins, spreadsheet cells, video timestamps, and more.

• The best ones add presence, notifications, screen recording, and calls for a full collaboration stack.

• Velt ships all of the above with React-ready components, a complete API, and optional self-hosting for data.

Why modern products need in-context discussion

Teams spend too much time copying URLs into chat apps and guessing which version of a file a teammate meant. In-app comments fix that friction. When feedback lives beside the thing under review, everyone stays on the same page.

Key gains for both users and builders

• Faster review loops: a reviewer clicks a highlight or pin and replies right away.

• A living audit trail: the chat sits inside the doc forever, so newcomers see past choices.

• Higher stickiness: people return to your product when the talk happens there instead of on Slack.

Commenting SDK vs Commenting API vs Build-from-scratch

An API helps but still leaves you building UI and handling sockets. An SDK goes further: it ships themed popovers, thread lists, presence badges, mentions, etc.

The cost of rolling your own

Building comments looks easy until edge cases surface:

A seasoned team can ship all of that, but it keeps them away from the features that set your product apart. Velt makes that overhead vanish. We actually just wrote an updated build vs buy guide for 2025.

Styles of comments you can ship

With Velt you do not pick just one. You can start with inline text this quarter and light up timestamp comments next quarter without pulling a new vendor.

Core features to watch for

• Precise anchors: pins stick even when content moves or resizes.

• Threaded replies: chats stay tidy rather than sprawling in one flat list.

• Resolution flow: mark done to keep the canvas clean.

• @mentions: tag a teammate and pull them in with one keystroke.

• Live presence: see cursors, selection boxes, and typing states for instant context.

• Rich reactions: a quick 👍 or ✅ means fewer “Looks good” posts.

• Notifications: in-product inbox and optional email for re-engagement.

• Recording: attach a 30-second video walkthrough when text falls short.

• Access rules: connect to your auth so private boards stay private.

• Theme: swap fonts, radius, and colors so the UI components blend into your brand.

• Custom functionality: go beyond themes with conditional UI + custom behavior.

Getting started with the Velt Commenting SDK

1. Install

   npm

2. Initialize the client

   // Root.tsx / App.jsx
   import {
     VeltProvider,
     VeltComments
   } from "@veltdev/react";
   import Auth from "./Auth";
   import Document from "./Document";
   
   export default function Root() {
     return (
       <VeltProvider apiKey={process.env.REACT_APP_VELT_API_KEY}>
         {/* renders comment threads UI */}
         <VeltComments />
   
         {/* your app */}
         <Auth />
         <Document />
       </VeltProvider>
     );
   }

   // Auth.tsx – identify the signed-in user
   import { useIdentify } from "@veltdev/react";
   
   export default function Auth() {
     const currentUser = { id: "u-123", name: "Ada Lovelace" };
     useIdentify(currentUser);          // must run inside VeltProvider
     return null;                       // no UI needed
   }

3. Make something commentable

   // Document.tsx – make something commentable
   import {
     VeltCommentTool,
     VeltPresence,
     useSetDocumentId
   } from "@veltdev/react";
   import MyRichTextEditor from "./MyRichTextEditor";
   
   export default function Document() {
     useSetDocumentId("my-document-id");  // tie comments to this doc
   
     return (
       <div className="my-doc">
         <VeltPresence />     {/* shows live cursors/avatars */}
         <VeltCommentTool />  {/* drop a pin or draw an area to comment */}
         <MyRichTextEditor />
       </div>
     );
   }

4. Style: drop CSS vars or Tailwind classes to match your palette.

5. Ship: open two tabs, leave a pin, and watch it sync live.

Read the full quickstart in our docs see advanced hooks and other setup.

Custom workflows with Velt webhooks

Velt fires real-time webhook events (e.g., actionType: newlyAdded or actionType: statusChanged). Point them at your backend to:

• post to a #design channel

• create a Jira ticket

• log usage for analytics

No extra polling or cron jobs needed.

Beyond comments: a full real-time layer

Comments spark the conversation, yet many teams soon ask for richer teamwork tools.

Because these add-ons share the same socket and auth, you can layer them without extra weight.

Real-world use cases

• Doc editors & wikis: redline policy docs or blog drafts inside the tool.

• Design platforms: pin feedback on a Figma-style canvas so art directors can review quickly.

• BI dashboards: let analysts chat over a spike on a chart and store that insight.

• Spreadsheet grids: drop cell notes in a finance model.

• E-learning: students mark a confusing paragraph and instructors reply in context.

• Dev sandboxes: leave code review notes on a line without switching to GitHub.

• Internal tools: support reps drop a question on the form they find tricky, turning comments into tickets.

Tips for picking the right SDK

1. Measure fit: draft a quick POC and let non-dev teammates play with it.

2. Review legal needs: some sectors need data self-hosted. Velt offers that.

3. Plan customization early: align the SDK with your styles + any custom behavior you need.

4. Look at roadmap: does the vendor ship new features often?

   
   

The best commenting SDKs for 2025 article shares pointers.

The road ahead

Collaboration no longer stops at file sharing. Users want chat, presence, voice, and rich media in the same window where they create value. A commenting SDK is the fastest step toward that future. Velt let you roll out threaded talk today and grow into live cursors, calls, and more tomorrow.