You should treat events in Move as lightweight logs that help both debugging and analytics, but with a focus on purpose—emit them when something meaningful happens like creation, transfer, refund, or error handling, rather than dumping every internal step; for debugging, you can design detailed events during development (e.g. including intermediate values) and later trim them down to only the fields your analytics pipeline or off-chain indexers truly need, while for analytics you keep them consistent and structured so you can track usage trends without bloating storage; a good practice is grouping related events in one module with clear naming (e.g. EscrowDeposited, EscrowReleased) and including only the minimal identifiers like object IDs, addresses, and amounts, instead of large payloads that increase gas; here’s an example pattern:

struct EscrowDeposited has copy, drop {
    escrow_id: ID,
    depositor: address,
    amount: u64,
}

struct EscrowReleased has copy, drop {
    escrow_id: ID,
    to: address,
    amount: u64,
}

public fun emit_deposit_event(e: &Escrow, who: address, amount: u64) {
    event::emit(EscrowDeposited { escrow_id: object::id(e), depositor: who, amount });
}

// TypeScript snippet: subscribing via @mysten/sui.js/client
import { SuiClient } from '@mysten/sui.js/client';
const client = new SuiClient({ url: 'https://fullnode.mainnet.sui.io' });
client.subscribeEvent({
  filter: { MoveModule: { package: '0xescrow', module: 'escrow' } },
  onMessage: (event) => {
    console.log('Escrow event:', event);
  },
});

Events in Move are like breadcrumbs—you drop them so you (or others) can retrace what your module actually did. The trick is deciding who you’re leaving the trail for:

• Debugging: emit granular events (like balance before/after, or which branch of logic executed). This helps you spot logic bugs quickly.
• Analytics / Indexing: emit higher-level events (e.g. TradeExecuted, PositionClosed) so off-chain services can build dashboards or track KPIs without parsing raw state.

To avoid clutter, I usually:

• Separate concerns: keep low-level debug events gated (e.g. only in dev/test versions), and keep mainnet events focused on user-meaningful actions.
• Use structured payloads: emit small, typed fields instead of dumping big structs. That keeps events cheap to emit and easy to parse.
• Think downstream: ask “will this event be useful six months from now?” If not, don’t bake it in—every event is permanent on-chain noise.

Best balance: emit just enough to reconstruct what happened without needing internal state diffs every step of the way.

Curious part: some teams even design events as part of their public API, so indexers treat them as the “truth” of what happened rather than raw storage reads. That’s powerful, but it locks you into your event design.