Template

PRD Template for Chat

A complete product requirements template for building chat and messaging features. Pre-filled with realistic examples for real-time messaging, threads, presence, file sharing, and moderation.

What makes chat PRDs different

Chat features are among the most technically demanding to build correctly. Users have been trained by WhatsApp, Slack, and iMessage to expect instant delivery, perfect reliability, and seamless offline handling. Anything less feels broken. This means your non-functional requirements are not aspirational targets — they are minimum viable thresholds.

The product challenge is equally difficult. Most products do not need general-purpose chat — they need contextual communication: comments on a document, discussions in a project, feedback on a design. Defining the right scope for chat in your product is the most important decision in the PRD. Building a full Slack competitor is almost never the right answer.

The template below covers both the technical requirements (real-time delivery, offline sync, presence) and the product decisions (scope, threading model, notification rules) that make or break a chat feature.

Chat PRD template

Eight sections covering every aspect of a chat and messaging feature.

01

Problem Statement

Chat features address the need for real-time communication within a product. Whether it is team collaboration, customer support, or social interaction, the core problem is the same: users need to communicate synchronously without leaving the product to use a separate messaging tool.

Example: "Our users currently switch to Slack or email to discuss work happening in our product, creating context fragmentation. In interviews with 30 power users, 87% said they switch between our product and a messaging tool more than 10 times per day. Context from these conversations (decisions, clarifications, feedback) is lost because it lives outside the product. 62% of users reported making decisions based on stale information because the relevant discussion happened in a Slack channel they were not in."

Tips

  • Measure how often users leave your product to communicate about work happening within it
  • Quantify the context loss from discussions happening outside the product
  • Identify the types of conversations users need to have (quick questions, feedback, group decisions)
  • Benchmark against the communication tools your users already use (Slack, Teams, Discord)
02

Goals and Objectives

Chat goals should focus on keeping conversations in context, reducing tool-switching, and improving decision traceability. The goal is not to replace Slack but to keep product-related discussions attached to the product artifacts they concern.

Example: "Primary: 60% of product-related discussions happen within the product (currently 0%) within 6 months of launch. Secondary: Reduce average context-switches per session from 10+ to under 3. Traceability: Every decision discussed in chat is linked to the artifact it affects. Latency: Messages delivered in under 200ms."

Tips

  • Set adoption targets relative to existing communication volume, not absolute numbers
  • Include a message delivery latency target — chat that feels slow will not be used
  • Define what "in-context" means: messages attached to specific projects, documents, or tickets
  • Set guard-rail metrics to ensure chat does not reduce productivity (time spent in chat per day)
03

User Stories

Chat user stories span one-on-one messaging, group conversations, threaded discussions, and contextual comments. Each interaction pattern has different requirements for notification, persistence, and discoverability.

Example: "As a team member, I want to start a threaded discussion on a specific paragraph of a document so that the conversation stays attached to the content it references. Acceptance criteria: threads can be started by selecting any text in a document; the thread appears in a side panel alongside the document; all participants are notified of new replies; threads are searchable and visible in the activity feed."

Tips

  • Write separate stories for 1:1 messaging, group chat, threaded discussions, and contextual comments
  • Include a story for message reactions as lightweight responses
  • Cover offline behavior: what happens to messages sent when the recipient is offline
  • Add a story for message editing and deletion with appropriate visibility rules
04

Functional Requirements

Chat requirements must cover message delivery, persistence, formatting, file sharing, presence, threading, and search. Real-time chat has more edge cases than most features — message ordering, offline sync, and concurrent editing all need specification.

Example: "FR-1: Messages must be delivered in real-time via WebSocket with a REST fallback for reconnection. FR-2: Messages must support rich text formatting (bold, italic, links, code blocks) and @mentions. FR-3: Users must be able to share files up to 25MB within a conversation. FR-4: Presence indicators must show online/offline/away status updated within 30 seconds. FR-5: Message history must be persistent and paginated (load 50 messages at a time, scroll up for more). FR-6: Users must be able to edit messages within 15 minutes and delete their own messages at any time."

Tips

  • Specify message size limits, file attachment limits, and supported file types
  • Define message ordering guarantees (important for concurrent conversations)
  • Include requirements for @mentions with notification behavior
  • Specify edit and delete policies: time windows, whether edits are marked, whether deletes are soft
05

Non-Functional Requirements

Chat systems have strict latency and availability requirements. Users expect messages to appear instantly and conversations to never lose messages. Chat downtime is highly visible — every user notices immediately.

Example: "NFR-1: Message delivery latency must be under 200ms at p95 for users in the same region. NFR-2: The chat system must maintain 99.9% uptime. NFR-3: Zero message loss — every message sent must be persisted and eventually delivered, even if the recipient is offline. NFR-4: Chat must support 1,000 concurrent WebSocket connections per server instance. NFR-5: Message search must return results within 500ms for conversations with up to 100,000 messages."

Tips

  • Set message delivery latency targets at p95, not average
  • Require zero message loss with at-least-once delivery guarantees
  • Define concurrent connection capacity for your deployment architecture
  • Include mobile performance targets (battery impact, data usage)
06

Success Metrics

Chat success metrics should measure adoption (are people using it instead of external tools?), engagement quality (are conversations productive?), and system reliability (are messages delivered?)

Example: "Metric 1: Percentage of product-related discussions in-product. Baseline: 0%. Target: 60%. Metric 2: Daily active chat users / daily active product users. Target: 50%+. Metric 3: Message delivery success rate. Target: 99.99%. Metric 4: Average response time in threads. Target: under 30 minutes during business hours. Metric 5: Context switches per session. Baseline: 10+. Target: under 3."

Tips

  • Track in-product discussion rate as the primary adoption metric
  • Measure chat DAU as a ratio of product DAU, not as an absolute number
  • Monitor message delivery reliability as a system health metric
  • Track thread resolution rate for support-oriented chat use cases
07

Technical Considerations

Chat architecture requires real-time message delivery (WebSocket), persistent storage, presence tracking, and offline sync. The choice between building on WebSocket directly, using Socket.io, or leveraging a managed service (SendBird, Stream Chat) significantly affects development timeline.

Example: "Real-time messaging will use Socket.io with Redis Adapter for horizontal scaling across multiple server instances. Messages are persisted in PostgreSQL with a compound index on (conversation_id, created_at) for efficient pagination. Presence is tracked via Redis with a 30-second heartbeat. Offline messages are delivered on reconnection by querying messages newer than the client's last-seen timestamp. File attachments are uploaded to S3 and referenced by URL in the message payload."

Tips

  • Evaluate build vs. buy: Socket.io/WebSocket (full control) vs. Stream Chat/SendBird (faster launch)
  • Plan for horizontal scaling of WebSocket connections from the start (Redis Adapter or similar)
  • Design message storage for efficient pagination and conversation-scoped queries
  • Implement offline sync from the beginning — retrofitting is expensive
08

Risks and Mitigations

Chat risks include message loss (users lose trust), adoption failure (users stick with Slack), and moderation gaps (harmful content). Each requires proactive mitigation.

Example: "Risk: Users do not adopt in-product chat because Slack is deeply embedded in their workflow. Likelihood: High. Impact: High. Mitigation: Start with contextual comments (attached to documents and tickets), not general-purpose chat. This provides unique value that Slack cannot replicate. Risk: Message loss during WebSocket reconnection. Likelihood: Medium. Impact: High. Mitigation: Implement client-side message queue with server-side delivery confirmation. Unconfirmed messages are retried on reconnection."

Tips

  • Address the adoption risk by offering unique value (contextual discussions) rather than competing with general-purpose chat
  • Plan for message loss prevention with delivery confirmation and retry logic
  • Consider moderation requirements, especially for B2B products (audit logging, message retention)
  • Address the risk of chat becoming a distraction that reduces productivity

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