PARI — Next-Generation Terminal Coding Agent

⚡ The Core Thesis

$$\text{\bf Agent failure is a systems engineering failure, not a reasoning failure.}$$

The exact same frontier reasoning model (Claude 3.7 Sonnet, GPT-4o) demonstrates a 15% pass rate in a naive loop, but achieves a 50–55% pass rate inside an engineered harness. The 35% delta is not model intelligence; it is accounted for by six fatal systems failure modes:

1. Unbounded stdout poisoning $\rightarrow$ Solved by Layer 7 (50KB/2k-line disk spooler + balanced head/tail extraction).
2. Mid-stream token truncation $\rightarrow$ Solved by Layer 4 (Strict stop_reason == "length" rejection guard).
3. File write race conditions $\rightarrow$ Solved by Layer 6 (FileMutationQueue canonical realpath serialization).
4. KV cache invalidation cascades $\rightarrow$ Solved by Layer 2 (Immutable Baseline Epochs freezing Tiers 1–4).
5. Blind file traversal loops $\rightarrow$ Solved by Layer 3 (v1: Fast substring ripgrep & globbing / v2: Tree-sitter AST fallback).
6. Unsandboxed host execution $\rightarrow$ Solved by Layer 0 (Multi-platform kernel isolation: bwrap, Seatbelt, E2B MicroVMs).

🚀 Installation & Quick Start

Official Website & Documentation: https://pari-cli.in

Choose your platform's installation command:

1. macOS & Linux (curl)

curl -fsSL https://pari-cli.in/install.sh | bash

2. Windows (irm in PowerShell)

irm https://www.pari-cli.in/install.ps1 | iex

3. Via pip / pipx / uv

# Recommended (isolated CLI)
pipx install pari-cli

# Fast via uv
uv tool install pari-cli

# Standard pip
pip install pari-cli

💻 Launch Interactive Session

# Export your API key
export ANTHROPIC_API_KEY="sk-ant-..."

# Launch PARI anywhere in your project workspace
pari-cli

⚖️ License

MIT License. See LICENSE for details.