Semble MCP Server

Semble is a code search library built for agents. It returns the exact code snippets they need instantly, using ~99% fewer tokens than grep+read. Indexing and searching a full codebase end-to-end takes under a second, matching the. That is what the semble mcp server brings to an AI assistant: the same capability, reachable through the Model Context Protocol rather than a separate app or dashboard.

Getting it running

Setup follows the usual MCP pattern — install or clone the server, register it in your client's configuration file, restart the client.

The tools it exposes

The server publishes 7 tools. What each one is for:

• Instructions — adds CLI usage guidance to AGENTS.md / CLAUDE.md
• Sub-agent — installs a dedicated semble-search sub-agent
• Fast — indexes an average repo in ~500 ms and answers queries in ~1 ms, all on CPU
• Accurate — NDCG@10 of 0.854 on our benchmarks, on par with code-specialized transformer models, at a fraction of the size and cost
• Token-efficient — returns only the relevant chunks, using ~99% fewer tokens than grep+read
• search — Search a codebase with a natural-language or code query. Pass repo as a local path or an https:// git URL
• find_related — Given a file path and line number, return chunks semantically similar to the code at that location

Things to watch

• It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
• Keep per-call confirmation enabled while you learn its behaviour; it is the cheapest safeguard you have.

How it compares

Plenty of developer tooling servers cover similar ground. The differences that matter in practice are scope of access and how much setup stands between you and a working tool call. Semble's toolset — Instructions, Sub-agent, Fast and 4 more — is a fair guide to whether it matches your workflow. It is maintained by minishlab; worth a glance at recent repository activity before you build anything load-bearing on it.

SyncDev reviews every entry in this directory against the project's own documentation before publishing, and revisits them as servers change.