
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.
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.
Installation
In SourceWeft
- Open Pare Cargo in the dashboard and add it to a workspace.
- 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:
Token estimates use ~4 chars/token. The biggest savings appear on verbose commands (builds, installs, tests). For simpler tools like
eslintortsc, 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 itstructuredContent— 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):
Pare structured output (~59 tokens):
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.
Tool Schemas — detailed response examples and field descriptions for every tool. See also Tool Response Examples for quick JSON samples.
Quick Setup
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:
Universal filter — restrict tools across all servers:
Disable all tools — set the env var to an empty string:
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:
In JSON MCP config, set via the env key:
Troubleshooting
Contributing
Each server is a self-contained package. See CONTRIBUTING.md for the full guide.
License
Source: README.md at commit 57e1980
Tools
0Version history
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