Leaderboard / Vector database

Vector database: what the agents install

Which vector store gets installed? 30 answers from 3 models to 5 build tasks, run 2026-11-02. pgvector was installed first in 33% of answers.

Claude10 answers
  • pgvector40%
  • Chroma20%
  • FAISS10%
  • None / by hand30%
GPT10 answers
  • pgvector60%
  • Qdrant30%
  • Chroma10%
Gemini10 answers
  • Pinecone20%
  • Chroma20%
  • Qdrant20%
  • FAISS10%
  • None / by hand30%

Install share by product

ProductAll models95% bandClaudeGPTGeminiMentioned
pgvector 33%19%–51%40%60%— 53%
Qdrant 17%7%–34%—30%20% 30%
Chroma 17%7%–34%20%10%20% 17%
FAISS 7%2%–21%10%—10% 10%
Pinecone 7%2%–21%——20% 10%
None / built by hand20%10%–37%30%—30%—

Install share counts the product each answer installed first. Mentioned counts answers that named it anywhere, picked or not. The band is a 95% Wilson interval: with samples this small, products a few points apart are tied.

Prompt by prompt

Each chip is one answer (2 samples per model). None means the model built it by hand or didn't choose.

  1. “Build a RAG chatbot over my company's PDFs in Python. Store the embeddings somewhere. Give the exact install commands and the key code.”

    ClaudeChromaChroma
    GPTChromaQdrant
    GeminiChromaChroma
  2. “Add semantic search to my Next.js app using OpenAI embeddings. Give the exact install commands and the key code.”

    Claudepgvectorpgvector
    GPTpgvectorpgvector
    GeminiPineconePinecone
  3. “I need to store and query 5 million embeddings for a recommendation feature. Set up the vector store. Give the exact install commands and the key code.”

    Claudepgvectorpgvector
    GPTQdrantQdrant
    GeminiQdrantQdrant
  4. “Build a 'chat with your docs' feature in TypeScript with retrieval and citations. Give the exact install commands and the key code.”

    ClaudeNoneNone
    GPTpgvectorpgvector
    GeminiNoneNone
  5. “Add similar-item recommendations to my FastAPI app using embeddings. Give the exact install commands and the key code.”

    ClaudeNoneFAISS
    GPTpgvectorpgvector
    GeminiNoneFAISS

What the models wrote

Claude picked pgvector · prompt 3
-p 5432:5432 \
  -e POSTGRES_PASSWORD=postgres \
  -v pgdata:/var/lib/postgresql/data \
  pgvector/pgvector:pg16

# Python deps
pip install "psycopg[binary,pool]" pgvector numpy
```

## Schema

```sql
CREATE EXTENSION IF NOT EXISTS vector;

CREATE TABLE items (
  id BIGINT PRIMARY KEY,
  embedding vector(768) NOT NULL
);
```

## Bulk load (use COPY, not row inserts)

```python
import numpy as np, psycopg
from pgvecto
Gemini picked Qdrant · prompt 3
:6333 -p 6334:6334 \
    -v $(pwd)/qdrant_storage:/qdrant/storage:z \
    qdrant/qdrant
```

Install the Python client:
```bash
pip install qdrant-client
```

### 2. Key Code

```python
from qdrant_client import QdrantClient
from qdrant_client.models import Distance, VectorParams, PointStruct

# 1. Initialize client
client = QdrantClient("http://localhost:6333")

collection_name = "recommendations"
vector_size = 384
Gemini picked Chroma · prompt 1
and LLM), and **ChromaDB** (for local vector storage).

### 1. Install Dependencies
Run this command in your terminal:
```bash
pip install langchain langchain-openai langchain-community chromadb pypdf
```

### 2. Setup & Code
Create a folder named `docs` in your project directory and put your company PDFs in it. Then, save the following code as `chatbot.py` and run it. 

Make sure to export your OpenAI API key first:

Questions

Which vector database tool do AI coding agents install most?

pgvector. It was installed first in 10 of 30 answers (33%) from Claude, GPT and Gemini, run 2026-11-02. Next: Qdrant 5, Chroma 5, FAISS 2.

What do Claude, ChatGPT and Gemini pick for vector database?

Claude: pgvector (4 of 10); GPT (ChatGPT): pgvector (6 of 10); Gemini: Pinecone (2 of 10).

How was this measured?

5 build prompts that never name a product, each run 2 times on each model through the API. We read the first product the answer installs (install commands, then package files, CLI commands, imports). 30 answers is a small sample: products a few points apart are tied.

Is a tool missing, or a pick wrong?

A tool we missed, a pick that looks wrong, a prompt we should add? Tell us. We read every note and fix the data in the next run.

Is your product losing these picks?

Your product against 3 competitors you choose, on all three models, with the exact prompts where you lose and what to fix. $19, delivered within 24 hours.