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Oh My Pi

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glm-5.3-flash
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Created: / Updated: / Status: finished / Readability: 3 / 10 minutes read (~1836 words)
agent-curated 592 cli 24 coding-agent 7 fork 2 fully-ai-generated 695 llm=glm-5.3-flash 602 lsp 2 research-note 562
Table of Contents

Oh My Pi (omp) is a batteries-included fork of the Pi harness, built by Stencil Labs, whose bet is that the IDE should be wired into the agent loop instead of the core staying frozen.

What it is
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A TypeScript CLI on Bun with a native Rust core of roughly 80,000 lines, MIT-licensed, distributed through an install script at omp.sh, Homebrew, bun/npm (@oh-my-pi/pi-coding-agent), Nix, and a Windows PowerShell script. It is a fork of Mario Zechner’s Pi (the badlogic/pi-mono line), and it keeps Pi’s extensibility while adding what Pi refuses to ship: 60-plus providers, 31 built-in tools, LSP operations wired into every write, DAP debugger control (lldb, dlv, debugpy), first-class subagents that fan out into worktrees and return typed results, an advisor model that watches every turn, live session sharing over /collab, and native Windows without WSL. The hook is the name of the design: everything your IDE knows, the agent knows.

Status
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Very active and past its parent in stars: 35,472 stars and 3,876 forks as of 2026-10-15 (GitHub API), on a repository created 2025-12-31 and pushed 2026-10-30 (GitHub API, as of 2026-10-30). The npm latest is 18.14.0 (published 2026-10-29), and the changelog logs a near-daily train with pull requests numbered past 16,000: 18.9.0 through 18.9.2 landed October 11 (fixes across apply_patch, local-model discovery, and fork spending inheritance), 18.10.0 landed October 12 (a /fork that opens a new Tern pane while a turn streams, omp session pack, unpack, and moved for carrying a session with its artifacts to another machine, omp auth export and import for model sign-ins, and a native owner-only transport for every local IPC endpoint including Windows named pipes), 18.10.1 followed the same day (a per-answer copy button in Tern), 18.10.2 and 18.10.3 landed that evening (late tool-update frames from background jobs now reach onDetachedToolUpdate subscribers instead of being dropped, and a breaking cleanup removing estimateImageContentTokens() in favor of Tokenizer.imageTokens(size, detail)), the 18.11.x train ran October 14 through 16 (18.11.0 added AgentTool.delegationGuidance for same-name extension replacements and dropped ApprovalDetailsOptions in a breaking cleanup, 18.11.3 tagged queued-message batches with their queue so prepareQueuedMessages can tell steering from follow-ups, and the pi-ai JSON Schema dereferencer stopped rewriting literal values in const, enum, and default positions), the 18.12 train ran October 17 through 21 (18.12.0 added ThinkingContent.narration for Anthropic and Bedrock thinking blocks marked as between-tool narration with presentNarrationAsAnswer to surface them as reply text, and replaced PI_CODEX_ZSTD with PI_REQUEST_COMPRESSION in a breaking cleanup, 18.12.1 fixed every request failing behind a TLS-inspecting proxy that refuses compressed uploads and removed display() from eval in both Python and JavaScript, 18.12.2 corrected the failed-tool-call feedback sent to DeepSeek models to also cover chat-template tool-call tokens and fixed Ollama chat-history estimates that skewed compaction after model switches, 18.12.3 added the approvalCacheTargets hook the always-ask-cached approval mode uses to check and record per-file grants and passed unknown root arguments to tools with lenientArgValidation, 18.12.4 enabled native compaction for supported Bedrock Claude models and added an opt-in reclaimAbovePct account policy for automatic session reclaim, 18.12.5 requested OpenAI’s 12-hour prompt-cache retention for GPT-5.6+ on the Responses API and fixed every OpenAI Codex request failing against the long-cache setting, and 18.12.6 added a prompt-cache-persistent catalog axis for providers whose endpoint caches never expire and refreshed the bundled Yolo-Auto catalog), and the 18.13 pair landed October 26 through 27 (18.13.0 rebuilt remote compaction to send cache and session headers for the endpoint it actually targets, added PI_ANTHROPIC_API_VERSION=2026-10-21 for the official Anthropic API, gave OpenCode Go shared-lane requests an explicit prompt-cache key so forks, Task siblings, and parents reuse one gateway cache, fixed repeated compaction on small or provider-capped windows, and broke OpenAIRequestSetupModel by requiring catalog-policy fields, and 18.13.1 added Agent.isPaused so hosts can tell paused agents from draining turns, stopped exhausted Codex spend-cap accounts being picked through credit overage, fixed Codex capacity 429s waiting hours instead of the server’s Retry-After, and added GPT-6.1 Terra and Kimi K3.1 Pro with Highspeed to the catalog, and 18.13.2 the same day let TUI extensions switch plan, vibe, goal, and loop modes directly through ctx.sessionModes with a mode_changed event instead of submitted slash commands, added draft-only speech-to-text capture with live previews for RPC hosts, let custom providers opt out of the reasoning ladder their /v1/models rows advertise through discovery.advertisedReasoning, scoped WATCHDOG advisor entries to main or subagent sessions, added session.worktreeScope to keep the resume picker scoped to one directory, and gave LM Studio decision models a judge role served over their /v1/decisions endpoint), and 18.14.0 landed October 29 (removing the Bun event-loop workaround utilities from @oh-my-pi/pi-agent-core/utils/yield in a breaking cleanup, adding AgentTool.approvalRestrictionPaths so restricted-folder approvals cover the paths a tool reads, Agent.logContext for custom fields on every run’s log records, Anthropic mTLS through the CLAUDE_CODE_CLIENT_CERT and CLAUDE_CODE_CLIENT_KEY environment variables, on-demand provider loading to cut startup and memory overhead, account-policy priority winning when usage information is unavailable, and credential prefetch during session setup, alongside breaking import moves of Anthropic header and endpoint helpers plus Codex session and OpenAI Responses replay helpers into dedicated provider modules). Contribution policy loosened from a vouch requirement to temporarily-open PRs while the maintainers evaluate how open contributions go. The Hacker News footprint is modest for the star count: a 42-point launch thread on July 21, 2026, and a 35-point “Harness Playbook” thread in September, which reads as adoption spreading through practitioners rather than through tech-media coverage.

Star History Chart

Strengths
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  • The strongest editor grounding in the terminal-harness field: renames go through LSP, and debugging happens through a DAP adapter (lldb, dlv, debugpy) instead of print statements.
  • It inherits what your other tools already wrote, reading Cursor MDC, Cline .clinerules, Codex AGENTS.md, Copilot applyTo, and more in their native shapes, plus MCP servers from .claude, .cursor, and friends on first run.
  • Coding-plan and OAuth routes cover the subscription you may already pay (Anthropic, OpenAI Codex, GitHub Copilot, Kimi Code, GLM Coding Plan), alongside 60-plus raw providers and local Ollama, LM Studio, llama.cpp, and vLLM endpoints.

Cautions
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  • Fork lineage is the structural risk: at 18.x against its parent’s 1.1.x, omp is a permanently diverging codebase, and a re-merge is not a realistic plan.
  • Subscription reuse carries terms-of-service risk: the launch thread’s sharpest comment reports provider OAuth flows warning that only official tools may log in, so routing a paid plan through omp could violate the provider’s terms.
  • The benchmark table in the README is self-run, and launch-thread commenters questioned the evaluation rigor (one called the CI “benchmaxxing” incomplete); the surface is also large enough that reviewing what omp does is a project of its own.

Pricing
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Free and MIT-licensed. There is no paid tier; usage flows through your own providers, subscriptions, or local servers, on their prices.

Compared to
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  • Pi: its parent, which keeps the core frozen and pushes features into extensions you can read in an afternoon; choose Pi for auditability, omp for the batteries.
  • Claude Code: the closed incumbent omp out-features on paper, with none of Anthropic’s first-party model economics.
  • OpenCode: the other big open terminal harness, provider-neutral like omp but without the LSP-first grounding.

Bottom line
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Recommended for power users who want IDE-grade diagnostics, debugger control, and heavy subagent fan-out in one terminal agent. Not for anyone who needs a small core they can fully audit, and not for ToS-cautious subscription reuse until the provider OAuth question is settled.

Changes
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  • 2026-10-10 - Created from the awesome-claude-code and GitHub topic scan, admitted as the batteries-included fork counterargument to the Pi column.
  • 2026-10-12 - Recorded the npm train reaching 18.10.1 (October 12) after 18.9.x on October 11, with 18.10.0 adding session pack and unpack across machines, auth export and import, streaming-turn /fork panes, and a native owner-only local IPC transport, and refreshed repository counters.
  • 2026-10-13 - Recorded the npm train reaching 18.10.3 (October 12 evening): 18.10.2 added onDetachedToolUpdate so late background tool-update frames reach subscribers, and 18.10.3 removed estimateImageContentTokens() in a breaking cleanup in favor of Tokenizer.imageTokens(size, detail), and refreshed repository counters.
  • 2026-10-17 - Recorded the npm train reaching 18.11.3 (October 16): the 18.11.x releases added AgentTool.delegationGuidance, broke out ApprovalDetailsOptions, tagged queued-message batches by queue in prepareQueuedMessages, and fixed the JSON Schema dereferencer rewriting literals in const and enum positions.
  • 2026-10-18 - Recorded the npm train reaching 18.12.1 (October 17): 18.12.0 added between-tool thinking narration for Anthropic and Bedrock with presentNarrationAsAnswer and replaced PI_CODEX_ZSTD with PI_REQUEST_COMPRESSION in a breaking cleanup, and 18.12.1 fixed requests behind TLS-inspecting proxies that refuse compressed uploads and removed display() from eval.
  • 2026-10-20 - Extended the release train through 18.12.3 (October 19): DeepSeek chat-template token corrections, Ollama compaction-estimate fixes, the approvalCacheTargets hook, and lenient argument validation.
  • 2026-10-24 - Extended the release train through 18.12.6 (October 21): Bedrock Claude native compaction with an opt-in reclaimAbovePct account policy, OpenAI 12-hour prompt-cache retention for GPT-5.6+ on the Responses API with its Codex failure fix, and the prompt-cache-persistent catalog axis, and refreshed the push date.
  • 2026-10-27 - Extended the release train through 18.13.1 (October 26-27): remote compaction pinned to the endpoint it actually targets, the Anthropic 2026-10-21 API version opt-in, OpenCode Go shared prompt-cache keys, repeated-compaction and Codex spend-cap/429 fixes, Agent.isPaused, and GPT-6.1 Terra plus Kimi K3.1 Pro catalog additions, with the breaking OpenAIRequestSetupModel catalog-policy requirement in 18.13.0.
  • 2026-10-28 - Recorded the npm train reaching 18.13.2 (October 27): extension-driven session-mode switching through ctx.sessionModes with a mode_changed event, draft-only speech-to-text capture for RPC hosts, the discovery.advertisedReasoning opt-out for custom providers, WATCHDOG advisor scopes, session.worktreeScope, and an LM Studio judge role over /v1/decisions.
  • 2026-10-29 - Recorded the npm train reaching 18.13.3 (October 28): manual-compaction start and end session events for RPC hosts, the retry.rateLimitWalksChain opt-in that walks the fallback chain on a 429 after signed Claude thinking, resume-picker session renames persisting as user titles, the display.advisorCollapsedLines cap, scope-aware omp config list output, and fixes from interrupt-suppressed background-job wakes to zsh/fish ! command prompts; refreshed the push date to 2026-10-29.
  • 2026-10-30 - Recorded npm latest reaching 18.14.0 (October 29): on-demand provider loading, AgentTool.approvalRestrictionPaths, Agent.logContext, Anthropic mTLS via client-certificate environment variables, and breaking cleanups moving provider helpers into dedicated modules; refreshed the push date to 2026-10-30 and the npm registry reference.

See also
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  • Pi - the frozen-core parent whose minimalism omp exists to argue with
  • Claude Code - the closed platform benchmark omp’s feature table is measured against
  • OpenCode - the other large open harness in the same buyer’s shortlist
  • Harness Feature Matrix - the capability comparison this column joins

References
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