phpcip/opensolr-mcp

mcp-name: com.opensolr/opensolr-mcp
MCP (Model Context Protocol) server for Opensolr —
gives any AI agent **managed Apache Solr search** as tools: hybrid
(BM25 + kNN) retrieval, server-side GPU embeddings, document indexing (local
files and folders too, PDFs page by page, scans through OCR), and grounded RAG
answers.
**See it live (real news index, hybrid + AI answer):** https://search.opensolr.com/news__dense?q=how+am+I+supposed+to+save+money%3F
No embedding model to configure. No vector database to run. One API key.
Tools
| Tool | What it does |
|---|---|
| opensolr_search | Hybrid (keyword + semantic) or pure semantic search, with Solr filters and a date range; a PDF comes back as its best page, with a link that opens it at that page |
| opensolr_search_by_image | Search with a **photo** — Opensolr reads its visual labels, OCR text and any barcode/QR, then searches with those words (no image vector stored) |
| opensolr_read_document | Read one result in full — a PDF page by page, any other document as one text |
| opensolr_ai_answer | Grounded RAG answer: top hybrid hits become the LLM context — same pipeline as the hosted search UI |
| opensolr_index_files | Index a local file or a whole folder: PDFs one document per page, Word / RTF / OpenDocument / text / HTML, scans and pictures through OCR |
| opensolr_extract_text | Read local files without indexing them: text, OCR of their pictures, a PDF page by page |
| opensolr_describe_image | What a picture shows (a sentence), the text printed on it, its labels and barcodes |
| opensolr_add_documents | Index plain text + metadata (embedded server-side) |
| opensolr_delete_documents | Remove documents by id |
| opensolr_list_indexes / opensolr_index_info | Inspect the account's indexes |
| opensolr_create_index | Provision a vector index in a region of opensolr_vector_regions (an environment id, or a short form like us matched against that live list) |
| opensolr_vector_regions | Live list of vector-enabled regions |
| opensolr_check_schema | Whether an index can do what each tool needs (Data Ingestion, vector and hybrid search, PDF pages, keyword search), and exactly why not |
| opensolr_apply_schema | Install the Opensolr vector schema on an index of a vector region (replaces its configuration; force when it holds documents) |
Setup
Get a free Opensolr account (free forever, no card) at
opensolr.com/register and copy your API key
from **Account**.
Try it without an account
There is a public demo account. Point the package at it and everything in this
README works immediately, with no signup:
mcp_demo_d1__dense is already loaded with 300 news articles, so search, filtering
and grounded answers work the moment you connect. You also get the write path:
create your own index on the account, ingest into it and query it. Deletion is not
available on this shared key: no index here can be deleted or reconfigured by hand.
Whatever you create is removed automatically after 3 days.
Know what you are working with:
- **Anything you create there is deleted after 3 days.** Automatically, without warning
or export. That includes indexes you created and every document in them.
- **The account is shared with everyone reading this.** Your index is visible to them
and they can add documents to it, as you can to theirs. Nobody can delete or
reconfigure an index here (that is switched off for this key), but never put anything
real, private or client-owned in it.
- **The limits are per index, and deliberately small.** 200 MB of bandwidth and 50 MB
of disk per index. Bandwidth is the one you will hit first: it covers a demo, a
tutorial and a proof of concept, and it will not carry an application.
When you want an index that is private, yours and still there next week, get your own
key — free forever, no card — and change the two
variables above. Nothing else in your code changes.
Claude Desktop / Claude Code
Cursor / Windsurf / any MCP client
Same shape — stdio transport, command uvx opensolr-mcp (or
pipx run opensolr-mcp), with OPENSOLR_EMAIL and OPENSOLR_API_KEY in env.
Example agent session
> **You:** Index our FAQ answers, then find everything about refunds.