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Moss loads an index into memory and runs embedding and search in-process, so a query is a local call with no network round trip per operation. The pattern is the same in every SDK: load the index once, then query it. 
await client.loadIndex(indexName)
const results = await client.query(indexName, 'How do I return a damaged product?', { topK: 3 })
Queries run against the in-memory index and embed the query text with a local model.

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The query pipeline

Query text is embedded locally, retrieved from an in-process loaded index, optionally reranked, and returned as resultsQuery text is embedded locally, retrieved from an in-process loaded index, optionally reranked, and returned as results
  • Load the index once, then query it in-process.
  • Optional background sync to the cloud.
  • Query pipeline: text -> embed -> retrieve -> rerank (optional).

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Prerequisites

  • Node.js 18+ or Python 3.10+
  • Moss credentials: MOSS_PROJECT_ID, MOSS_PROJECT_KEY
  • An index to query (create faqs via the Quickstart if you don’t have one yet)

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Steps

1

Export credentials (and index if different)

export MOSS_PROJECT_ID=your_project_id
export MOSS_PROJECT_KEY=your_project_key
export MOSS_INDEX_NAME=faqs   # or your index
2

Ensure the index exists

Ensure the index exists (see Quickstart to create faqs).
3

Run one of the snippets below

Run one of the snippets below.

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Run the sample (JavaScript or Python)

import { MossClient } from '@moss-dev/moss'

const client = new MossClient(
  process.env.MOSS_PROJECT_ID!,
  process.env.MOSS_PROJECT_KEY!
)

const indexName = process.env.MOSS_INDEX_NAME || 'faqs' // ensure this exists (see Quickstart)

async function main() {
  await client.loadIndex(indexName)
  const results = await client.query(indexName, 'How do I return a damaged product?', { topK: 3 })

  console.log(`Found ${results.docs.length} docs in ${results.timeTakenInMs}ms`)
  results.docs.forEach((doc, i) => {
    console.log(`${i + 1}. [${doc.id}] ${doc.text} (score: ${doc.score.toFixed(3)})`)
  })
}

main().catch(console.error)

import os
import asyncio
from moss import MossClient, QueryOptions

project_id = os.getenv("MOSS_PROJECT_ID")
project_key = os.getenv("MOSS_PROJECT_KEY")
index_name = os.getenv("MOSS_INDEX_NAME", "faqs")  # ensure this exists (see Quickstart)

async def main():
    client = MossClient(project_id, project_key)
    await client.load_index(index_name)
    results = await client.query(index_name, "How do I return a damaged product?", QueryOptions(top_k=3))

    print(f"Found {len(results.docs)} docs")
    for i, doc in enumerate(results.docs, 1):
        print(f"{i}. [{doc.id}] {doc.text} (score: {doc.score:.3f})")

asyncio.run(main())
The sample loads your index into memory and returns the top matches. An index must be loaded with loadIndex / load_index (or opened as a session) before you can query it.