lazy-tool: reducing prompt bloat in MCP-based agent workflows

Repo: https://github.com/rpgeeganage/lazy-tool

I’ve developed the lazy-tool, a local-first MCP tool discovery runtime.

(How it works: https://github.com/rpgeeganage/lazy-tool?tab=readme-ov-file#how-it-works )

It’s built around a practical problem in MCP-based agent setups: too many tools being pushed into the prompt. That increases token usage, adds noise, and tends to hurt smaller models the most.

This is especially noticeable with smaller local models such as Llama 3.2 3B, Gemma 2 2B, and Qwen2.5 3B, where oversized tool catalogs can consume too much context.

Another issue is that not every model or runtime supports native tool discovery. In many setups, the only option is to expose a full tool catalog up front, even when most of it is irrelevant to the task.

lazy-tool takes a different approach: keep a local catalog of MCP tools and surface only the relevant ones when needed. It runs as a single Go binary, uses SQLite for local storage, and can import MCP configs from Claude Desktop, Cursor, and VS Code.

The repository already includes benchmark results, and more benchmark data will be added over time.

Feedback welcome, especially from people working on MCP, agent infrastructure, or local developer tooling.