ai.voxell/forge
MCP server for Forge, Voxell's embedding API. Voxell's Ingot-8B-R3 ranks #1 for English on MTEB.
What can you do with ai.voxell/forge?
- Add semantic search — embed your documents with
input_type: "document"and each query - Build RAG — embed a knowledge base, store the vectors, and retrieve the closest chunks to
- Find similar or duplicate text — embed two texts and compare their vectors.
- Cluster or classify — embed a batch, then cluster or train a classifier on the vectors.
- Shrink vector storage — set
dimto truncate (Matryoshka) and trade a little accuracy - Straight from your editor — ask your AI agent (Cursor, Claude, …) to embed a snippet, a
Install
Add this to your client's MCP configuration (Claude Desktop: claude_desktop_config.json; Cursor: .cursor/mcp.json; VS Code and others use the same "mcpServers" shape).
@voxell/forge-mcpclaude mcp add forge -e 'FORGE_API_KEY=<your forge_api_key>' -- npx -y @voxell/forge-mcp@0.1.6
{
"mcpServers": {
"forge": {
"command": "npx",
"args": [
"-y",
"@voxell/forge-mcp@0.1.6"
],
"env": {
"FORGE_API_KEY": "<your forge_api_key>"
}
}
}
}
Environment variables
FORGE_API_KEYrequired secret Your Forge API key — create one at https://dash.voxell.ai (turbo is free forever, no card).
Documentation
From the project's README on GitHub, refreshed weekly. Links open on GitHub.
Contents
@voxell/forge-mcp
An MCP server for Forge — Voxell's hosted text-embedding API. It exposes Forge to any MCP client (Claude, Cursor, Cline, Windsurf, VS Code, …) as two tools:
embed— turn text into vectorslist_models— list available models and their dimensions
You bring a Forge API key. The server is stateless, and Voxell does not store the text you send or the vectors it returns — only usage metadata (token counts) is recorded, for billing. It does embeddings only — no storage, no search, no RAG. Those are different products.
Quick install
One-click install in your editor (then replace your-key-here with a real key from
dash.voxell.ai):
Claude Code — one command:
claude mcp add forge -e FORGE_API_KEY=your-key-here -- npx -y @voxell/forge-mcp
Any other client (Claude Desktop, Cline, Windsurf, Zed, …) uses the standard mcpServers
block — see Use it below.
Why Forge
- Quality you can dial. Three tiers:
turbo(1024d, fast, the default),pro(2560d) andultra(4096d, highest quality). Pick your point on the quality and cost curve. - Benchmark-leading. Voxell's Ingot-8B-R3 ranks #1 for English on the public MTEB leaderboard (English v2), with a 75.98 mean task score across 41 tasks: the top usable English embedding model. See the model card.
- Measured on public documents. Voxell's retrieval pipeline, built on Forge, is measured on four public corpora (7,817 documents, 980,885 passages). On 800 model-written questions, which are easier than a test set written by people, the first result answers the question for 83%. Method and limits: Measured retrieval.
- Matryoshka (MRL). Set
dimto truncate (re-normalized) for ~4× smaller, cheaper vectors. - Low latency (Go + CUDA engine), zero-trust (per-key auth; mTLS available), and free to
start (
turbois free forever, no card: dash.voxell.ai; more at voxell.ai/forge).
Measured retrieval
This server returns vectors only. Voxell also runs a retrieval pipeline built on Forge, and publishes what it measures on documents anyone can read.
Four public corpora, 7,817 documents and 980,885 passages in total, 800 questions (200 per corpus), measured 2026-10-05:
| corpus | documents | first result answers the question | one of the top three answers it |
|---|---|---|---|
| SEC filings | 2,010 | 91% | 95% |
| USPTO patents | 4,008 | 86.5% | 91.5% |
| NASA technical reports | 1,210 | 67% | 78% |
| arXiv technical papers | 589 | 86.5% | 96% |
| all four | 7,817 | 83% | 90% |
The right document is in the top ten for 95% of the questions.
Read these numbers for what they are. The questions were written by a model from the documents
and judged against the passage text, which is easier than a test set written by people. The
numbers describe what this pipeline does on these corpora. They are not a comparison with any
other vendor, and they are not what the embed tool does on its own: the pipeline adds the steps
the receipts list, such as a cross-encoder reranker, a one-line document identity in every
passage, and routing to the documents a question names. Each receipt is published with a fixed
sample of its questions, misses included: voxell.ai/retrieval.
What you can do with it
- Add semantic search — embed your documents with
input_type: "document"and each query withinput_type: "query", then rank by cosine similarity. - Build RAG — embed a knowledge base, store the vectors, and retrieve the closest chunks to ground an LLM.
- Find similar or duplicate text — embed two texts and compare their vectors.
- Cluster or classify — embed a batch, then cluster or train a classifier on the vectors.
- Shrink vector storage — set
dimto truncate (Matryoshka) and trade a little accuracy for smaller, cheaper vectors. - Straight from your editor — ask your AI agent (Cursor, Claude, …) to embed a snippet, a
batch, or a file via the
embedtool — no separate script.
Requirements
- Node.js ≥ 18 (tested on 20)
- A Forge API key — create one at https://dash.voxell.ai.
turbois free forever, no card.
Use it
Most MCP clients run it on demand with npx. Add this to your client's MCP config:
{
"mcpServers": {
"forge": {
"command": "npx",
"args": ["-y", "@voxell/forge-mcp"],
"env": { "FORGE_API_KEY": "your-key-here" }
}
}
}
(Cursor, Claude Desktop, Cline, Windsurf, and VS Code all use this mcpServers shape.)
Tools
embed
| arg | type | default | notes | |
|---|---|---|---|---|
input | string or string[] | — | text(s) to embed (required) | |
model | string | turbo | turbo (1024-d), pro (2560-d), ultra (4096-d) | |
dim | number | model default | truncate to N dimensions (Matryoshka) — works on every model | |
input_type | "query" \ | "document" | document | use query for search queries |
Returns the vectors plus the model, dimension, and token count.
Default is turbo — the one you probably want. pro/ultra trade size and speed for more
dimensions.
list_models
Lists the available models and their dimensions.
Configuration
| env | required | default |
|---|---|---|
FORGE_API_KEY | yes | — |
FORGE_BASE_URL | no | https://api.voxell.ai |
Beyond MCP: OpenAI-compatible API
Forge speaks the OpenAI embeddings API. Point any OpenAI client at Forge — no code change, and your existing vector dimensions are preserved:
from openai import OpenAI
client = OpenAI(base_url="https://api.voxell.ai/v1", api_key="your-forge-key")
# the exact call you already make — now on a higher-ranked engine:
client.embeddings.create(model="text-embedding-3-large", input=["hello world"]) # -> 3072-d
Your OpenAI model names map to a matching-dimension Forge tier (text-embedding-3-small/
ada-002 → 1536-d, text-embedding-3-large → 3072-d), so existing vector stores slot in
unchanged. Or address Forge tiers directly — turbo | pro | ultra. Also supports dimensions
(Matryoshka, re-normalized) and encoding_format: "base64".
It's an upgrade on every path. Forge's smallest tier (turbo) outranks OpenAI's
largest embedding model (text-embedding-3-large) on MTEB, so there's no drop-in that lands
worse. And Voxell's Ingot-8B-R3 ranks #1 for English on the public MTEB leaderboard: a different
league.
Why re-embedding onto Forge is worth it. Embedding is a one-way door: whatever an encoder discards at write time is gone — no reranker, longer prompt, or bigger LLM downstream reconstructs what the vectors never captured. The model you embed with sets the ceiling on everything above it. Re-embed once onto a higher-ranked engine and that ceiling rises — permanently.
License
MIT © Voxell, Inc.
Frequently asked questions
What is ai.voxell/forge?
MCP server for Forge, Voxell's embedding API. Voxell's Ingot-8B-R3 ranks #1 for English on MTEB.
How do I install ai.voxell/forge?
It runs on your machine. In Claude Code: claude mcp add forge -e 'FORGE_API_KEY=<your forge_api_key>' -- npx -y @voxell/forge-mcp@0.1.6. For other clients, paste the JSON configuration from this page into their MCP settings.
Does ai.voxell/forge need an API key?
Yes. It expects FORGE_API_KEY, which you set in its configuration.
Is ai.voxell/forge open source?
Yes. Its code is on GitHub under the MIT license.
Who maintains ai.voxell/forge?
It is published by VoxellInc. AI.tn lists it but does not maintain or endorse it.
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