chroma-local

name	chroma-local
description	Use when the user needs self-hosted or local Chroma for semantic search, including `ChromaClient`, `HttpClient`, or Python `EphemeralClient`, local persistence, Docker or `chroma run`, or OSS Chroma without Chroma Cloud features.

Instructions

Determine these before writing code. Prefer discovering them from the repo and the user request. Ask only when the choice materially changes the implementation.

1. Runtime shape

   • Are they connecting to a running local server, embedding Chroma into tests, or setting up local development from scratch?
   • Decide whether they need chroma run, a Docker or service command, HttpClient or ChromaClient, or Python EphemeralClient.

2. Persistence

   • Persistent local data: choose an intentional data path.
   • Disposable test data: use defaults or a temp directory.

3. Embedding model

   • Reuse the app's existing embedding provider when possible.
   • Otherwise default to @chroma-core/default-embed in TypeScript or the standard local default in Python.
   • If the user explicitly wants OpenAI embeddings in TypeScript, install and use @chroma-core/openai.

4. Indexed data shape

   • Determine what is being indexed, how it should be chunked, and what metadata is needed for filtering and updates.

Routing

• Existing local server

  • Confirm host and port before changing client code.
  • Validate the server is reachable before assuming collections are missing.

• Fresh local development

  • Add a local startup path such as chroma run or the repo's existing Docker or service command.
  • Default to localhost:8000 unless the repo already uses another address.

• Python tests or disposable local workflows

  • Prefer EphemeralClient when persistence is unnecessary.
  • Call out that data is lost when the process exits.

• Persistent local development

  • Use a stable data path and make persistence explicit in code or config.
  • Do not silently switch between ephemeral and persistent modes.

• Search integration work

  • Use getOrCreateCollection() in TypeScript or get_or_create_collection() in Python.
  • Design document IDs and metadata so upserts and deletes are straightforward.
  • Batch writes when syncing large datasets.

Ask vs proceed

Ask first:

• Embedding model choice (cost and quality implications)
• Whether they need persistent local data
• How they are starting the local server
• Multi-tenant data isolation strategy

Proceed with sensible defaults:

• Use getOrCreateCollection() (TypeScript) / get_or_create_collection() (Python)
• Use cosine similarity (most common)
• Chunk size under 8KB
• Store source IDs in metadata for updates/deletes
• Use a local server on localhost:8000 unless the repo already configures another address or is using Python EphemeralClient

What to validate

• Correct client import (ChromaClient, HttpClient, or Client)
• Embedding function package is installed (TypeScript)
• Local server is reachable before assuming collections are missing
• Local path and persistence mode are intentional

Implementation notes

• Local Chroma is the right default for development, tests, and self-hosted deployments.
• OSS Chroma does not include Chroma Cloud-only features such as Schema() and Search().
• If the user asks for hybrid dense and sparse retrieval, treat that as a likely Chroma Cloud requirement unless the repo already implements an OSS workaround.
• For open source Chroma, dense retrieval with a single embedding function is the normal baseline.

Minimal patterns

Start a local Chroma server when the repo needs one:

chroma run

Default address: localhost:8000.

TypeScript local client:

import { ChromaClient } from 'chromadb';
import { DefaultEmbeddingFunction } from '@chroma-core/default-embed';

const client = new ChromaClient();

const embeddingFunction = new DefaultEmbeddingFunction();
const collection = await client.getOrCreateCollection({
  name: 'my_collection',
  embeddingFunction,
});

// Add documents
await collection.add({
  ids: ['doc1', 'doc2'],
  documents: ['First document text', 'Second document text'],
});

// Query
const results = await collection.query({
  queryTexts: ['search query'],
  nResults: 5,
});

Python local client:

import chromadb

client = chromadb.HttpClient(host="localhost", port=8000)

collection = client.get_or_create_collection(name="my_collection")

# Add documents
collection.add(
    ids=["doc1", "doc2"]   ,
    documents=["First document text", "Second document text"],
)

# Query
results = collection.query(
    query_texts=["search query"],
    n_results=5,
)

Learn More

Fetch Chroma's llms.txt only when you need API or product details that are not already in the repo or this skill: https://docs.trychroma.com/llms.txt