oh-my-pi (omp) — A Coding Agent with the IDE Wired In

oh-my-pi (omp) is an open-source, terminal-first coding agent harness — a fork of Mario Zechner's Pi rewritten as a batteries-included developer surface. It spans ~345K lines of TypeScript (Bun runtime) and ~55K lines of Rust (N-API addon), bundling 32 built-in tools, 40+ LLM providers, a TUI, memory systems, subagent orchestration, browser automation, and collaboration support.

Its core thesis is that harness correctness matters more than model intelligence: in-process native tools (ripgrep, bash, tree-sitter), content-hash-anchored editing (Hashline), and time-traveling stream rules (TTSR) eliminate whole classes of editing and tool-calling errors upstream of the model. The README cites Grok Code Fast 1 jumping from 6.7% to 68.3% pass rate purely by fixing the edit format.

Architecturally, omp layers agent orchestration, session management, and TUI rendering in TypeScript over a Rust native addon that runs grep, shell, AST analysis, and token counting in-process — no fork/exec on the hot path. Sessions are append-only JSONL with tree-shaped branching. Two independent memory systems (Hindsight markdown pipeline and Mnemopi SQLite+vector store) feed context into future sessions.

The project makes deliberate trade-offs: monorepo complexity (14 npm packages + 6 Rust crates) for tight integration, a Rust native layer for portability across platforms without binary dependencies, and configuration inheritance from eight competitor formats for adoption ease. Notable weaknesses include tool sprawl (32 tools for the model to navigate, mitigated by BM25-indexed discovery) and compaction-system complexity with six trigger paths.