Pare Cargo

io.github.Dave-LondonPublished by GitHub account Dave-Londonv0.8.1Updated Oct 28, 2026

Pare Cargo ג€” Structured Rust cargo operations (build, test, clippy, fmt, doc) as typed JSON.

VerifiedSTDIODesktop onlyDeveloper ToolsAI & ML

Overview

AI-generated overview

Wraps Rust cargo commands (build, test, clippy, fmt, doc) and returns schema-validated JSON instead of raw terminal text.

What you can do
  • Run cargo build and capture errors and help text as typed JSON
  • Run cargo test and get per-test results and failure summaries
  • Run clippy, fmt and doc checks with structured findings
  • Return both human-readable text and schema-validated structuredContent for each tool
When to use it
Useful when an assistant works on Rust projects and needs reliable, compact build, test and lint results instead of parsing cargo's terminal output, which varies by platform, version and locale.
Requirements
Runs locally over stdio via the npm package @paretools/cargo, so Node.js 20 or newer and npx are needed; the cargo toolchain must be installed on the machine. Optional PARE_CARGO_TOOLS or PARE_TOOLS environment variables limit which tools are registered.
Before you install
Tools execute real cargo commands in the project, so builds, tests and formatting can modify files or the target directory; restrict tools with the PARE_CARGO_TOOLS or PARE_TOOLS environment variables if you want read-only behaviour. No credentials are requested.

Installation

In SourceWeft

  1. Open Pare Cargo in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

[Image]  Pare

[CI] [codecov] [npm] [Downloads] [TypeScript] [License: MIT] [Node.js >= 20] [OpenSSF Scorecard] [OpenSSF Best Practices]

Reliable, structured CLI output for AI agents — no more parsing fragile terminal text.

Pare provides MCP servers that wrap common developer tools (git, npm, docker, test runners, etc.) and return clean, schema-validated JSON instead of raw terminal text. Agents get typed data they can act on directly, without brittle string parsing.

The Problem

Parsing CLI output is fragile. Raw terminal text includes ANSI escape codes, decorative headers, progress bars, locale-specific formatting, and platform differences that break agent workflows in subtle ways. An agent that works fine with git status on macOS may fail on Windows because the output format changed. A test runner's summary line might shift between versions, silently breaking a regex.

Pare eliminates this entire class of errors by returning schema-validated JSON with consistent field names, regardless of platform, tool version, or locale. As a bonus, structured output is significantly smaller — agents use fewer tokens per tool call:

Tool CommandRaw TokensPare TokensReduction
docker build (multi-stage, 11 steps)3732095%
git log --stat (5 commits, verbose)4,99238292%
npm install (487 packages, warnings)2414183%
vitest run (28 tests, all pass)1963980%
cargo build (2 errors, help text)43613868%
pip install (9 packages, progress bars)28810165%
cargo test (12 tests, 2 failures)35119046%
npm audit (4 vulnerabilities)28718536%

Token estimates use ~4 chars/token. The biggest savings appear on verbose commands (builds, installs, tests). For simpler tools like eslint or tsc, the main advantage is reliable structured data — agents can use typed JSON directly rather than parsing strings.

How It Works

Each Pare tool returns two outputs:

  • content — human-readable text, for MCP clients that display it
  • structuredContent — typed, schema-validated JSON, ready for agents to process

This uses MCP's structuredContent and outputSchema features to provide type-safe, validated data that agents can rely on without custom parsing.

Example: git status

Raw git output (~118 tokens):

On branch mainYour branch is ahead of 'origin/main' by 2 commits.  (use "git push" to publish your local commits)
Changes to be committed:  (use "git restore --staged <file>..." to unstage)        modified:   src/index.ts        new file:   src/utils.ts
Changes not staged for commit:  (use "git add <file>..." to update what will be committed)  (use "git restore <file>..." to discard changes in working directory)        modified:   README.md
Untracked files:  (use "git add <file>..." to include in what will be committed)        temp.log

Pare structured output (~59 tokens):

json
{  "branch": "main",  "upstream": "origin/main",  "ahead": 2,  "staged": [    { "file": "src/index.ts", "status": "modified" },    { "file": "src/utils.ts", "status": "added" }  ],  "modified": ["README.md"],  "deleted": [],  "untracked": ["temp.log"],  "conflicts": [],  "clean": false}

50% fewer tokens. Zero information lost. Fully typed. Savings scale with output verbosity — test runners and build logs see 80–92% reduction.

Available Servers (28 packages, 240 tools)

Install only the servers relevant to your stack — most projects need just 2–4. The full catalog covers a wide range of ecosystems so Pare works wherever you do.

CategoryServersToolsWraps
Version Controlgit, github55git, gh
Languages & Packagesnpm, python, cargo, go, deno, bun, nix, dotnet, ruby, swift, jvm101npm, pip, cargo, go, deno, bun, nix, dotnet, gem, swift, gradle, maven
Build, Lint & Testbuild, lint, test, cmake, bazel23tsc, esbuild, vite, webpack, eslint, prettier, biome, vitest, pytest, jest
Infrastructuredocker, k8s, infra, security, remote40docker, kubectl, helm, terraform, ansible, trivy, ssh
Utilitiessearch, http, make, process, db21ripgrep, fd, curl, make, just, psql, mysql, redis, mongosh

Tool Schemas — detailed response examples and field descriptions for every tool. See also Tool Response Examples for quick JSON samples.

Quick Setup

bash
# 1. Configure MCP servers (non-interactive)npx @paretools/init --client claude-code --preset web
# 2. Add agent rules to your project#    (append to existing CLAUDE.md, or copy if new)cat node_modules/@paretools/init/rules/CLAUDE.md >> CLAUDE.md
# 3. Restart your client session
# 4. Validatenpx @paretools/init doctor

Available presets: web, python, rust, go, jvm, dotnet, ruby, swift, mobile, devops, full

Setup Guides by Client

Full Quickstart Guide — presets, ecosystem mapping, validation

Manual Configuration — config paths and formats for all clients

Agent Integration Guide — rule files, hooks, CLI-to-MCP mapping

Configuration

Tool Selection

By default, every Pare server registers all of its tools. If a server exposes tools you don't need — or you want to limit which tools are available to an agent — you can filter them with environment variables.

Per-server filter — restrict a single server's tools:

bash
# Only register status and log in the git serverPARE_GIT_TOOLS=status,log npx @paretools/git

Universal filter — restrict tools across all servers:

bash
# Only register these specific tools across any serverPARE_TOOLS=git:status,git:log,npm:install npx @paretools/git

Disable all tools — set the env var to an empty string:

bash
PARE_GIT_TOOLS= npx @paretools/git   # no tools registered
Env VarScopeFormatExample
PARE_TOOLSAll serversserver:tool,...git:status,npm:install
PARE_{SERVER}_TOOLSOne servertool,...status,log,diff

Rules:

  • No env var = all tools enabled (default)
  • PARE_TOOLS (universal) takes precedence over per-server vars
  • Server names use uppercase with hyphens replaced by underscores (e.g., PARE_MY_SERVER_TOOLS)
  • Whitespace around commas is ignored

Common patterns:

bash
# Read-only git (no push, commit, add, checkout)PARE_GIT_TOOLS=status,log,diff,branch,show
# Minimal npmPARE_NPM_TOOLS=install,test,run
# Only specific tools across all serversPARE_TOOLS=git:status,git:diff,npm:install,test:run

In JSON MCP config, set via the env key:

json
{  "mcpServers": {    "pare-git": {      "command": "npx",      "args": ["-y", "@paretools/git"],      "env": {        "PARE_GIT_TOOLS": "status,log,diff,show"      }    }  }}

Troubleshooting

IssueSolution
npx not found / ENOENT on WindowsUse cmd /c npx wrapper (see your client's setup guide)
Slow first startRun npx -y @paretools/git once to cache, or install globally: npm i -g @paretools/git
Node.js version errorPare requires Node.js >= 20
NVM/fnm PATH issuesUse absolute path to npx: e.g., ~/.nvm/versions/node/v22/bin/npx
MCP connection timeoutSet MCP_TIMEOUT=30000 for Claude Code, or increase initTimeout in client config
Too many tools filling contextUse tool selection env vars to limit tools, or only install the servers you need

Contributing

Each server is a self-contained package. See CONTRIBUTING.md for the full guide.

License

MIT

Source: README.md at commit 57e1980

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v0.8.1LatestSep 16, 2026

Score

50% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • Auth declared10 pts

    Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.

  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts