Rating certificate · AW/26-09/80226 Sept 2026
84of 100
The Register / Coding agents / Pi
Register entry · Coding agents · updated 26 Sept 2026
Pi
Pi is an MIT-licensed coding agent CLI that starts with four tools (read, write, edit, bash) and leaves most behaviour to extensions, skills, prompt templates and packages. It ships in a monorepo with a unified LLM API, agent core and TUI that other projects (e.g. OpenClaw) build on. Sessions are stored as trees in JSONL files. Pi has no built-in permission system or sandbox; its docs point to containers or VM sandboxes for isolation.
What reviewers and users praise
- Context control and session trees praised by users and reviewers (Glukhov, Luis Mori, HN)
- Highly extensible; used as the base for other agents (Kocsis, HN)
- Provider freedom lets users cut costs with cheaper models (HN)
What they criticise
- No built-in permission system or sandbox (README; Glukhov)
- Users must assemble their own workflow; steeper for beginners (Glukhov, Luis Mori)
- Reliability issues with some providers and auto-compaction (GitHub issues)
Experts vs the crowdneeds both scores
Experts75
Crowd—
| Price | Free |
|---|---|
| Use it via | CLI, API |
| Runs on | macos, linux, windows |
| Licence | MIT |
| Updated | Evidence collected 26 Sept 2026 |
How the rating was worked out
Weights for Coding agents: adoption 35%, experts 40%, crowd 25%. Pillars without enough evidence are left out and the others re-weighted. The method.
| Adoption & momentumweight 35% | 95 | GitHub stars 109k → 92 · npm weekly downloads 2.8M → 93 · 23 releases in 90 days → 100reach × 0.7 + momentum × 0.3 |
|---|---|---|
| Expertsindependent reviews · weight 40% | 75 | 3 independent reviews (3 positive · 0 mixed · 0 negative), averaged toward 50 for small samples. |
| Crowdcommunity sample · weight 25% | — | Community sample from a single platform |
| Rating | 84 | Provisional: low confidence (2 of 3 pillars, 7 community posts). |
Evidence checks. 2 GitHub issues not counted as sentiment. 2 items could not be checked at the source (the page could not be fetched, or the quote is from a comment under the linked post); kept and marked “unverified”. How evidence is checked.
Trust & safety
Seven dimensions graded A–D from documented facts. Overall: B.
C
Permission model
README: Pi has no built-in permission system; runs with the permissions of the launching user. Isolation is opt-in via containers/sandboxes (three patterns documented; Gondolin VM extension). Project trust controls which project resources load. source
B
Data access scope
Broad access (user-level filesystem, process, network), explicitly documented. source
A
Data storage
Runs locally; sessions stored as local JSONL files; no required cloud storage. source
n/e
Data retention & training
Retention/training governed by the user's chosen model provider; no Pi-level statement verified. Monorepo includes a pi-telemetry package; its defaults not verified. source
C
Incident history (24 months)
Four CVEs published 2026-06-08, including one high-severity local privilege escalation; patched in 0.78.1/0.79.0. source
D
Compliance
No attestations; open-source developer tool. source
A
Transparency
MIT licence with public GitHub releases. source
The experts
3 named independent reviews found; dated reviews from the last 12 months are scored.
- positive
Pi’s greatest weakness and greatest strength are the same thing: it does not finish the agent for you.
Rost Glukhov · 14 Aug 2026 · glukhov.org - positive
The thesis holds: Pi is a harness-first tool for engineers who want control over what enters the model
Luis Mori · 7 Jul 2026 · luismori.dev - positive
why its deliberate minimalism is its most interesting quality.
Balazs Kocsis · 28 Jun 2026 · unverified · medium.com
The crowd
7 coded posts from hackernews.
6 positive1 mixed0 negative
- positive
I can’t tolerate anything other than Pi anymore.
Hacker News comment · 23 Sept 2026 · news.ycombinator.com - positive
Love Pi because it does a good job managing the context
Hacker News comment · 23 Sept 2026 · news.ycombinator.com - positive
I've been using it exclusively (and extending it
Hacker News comment · 2 Jul 2026 · news.ycombinator.com - positive
Pi is the first, and and only agent I've ever seriously used
Hacker News comment · 6 Jul 2026 · news.ycombinator.com - positive
convinced me to exit my $200/month burden and pick up Pi Coding Agent and Deepseek V4 Flash 0731.
Hacker News comment · 13 Aug 2026 · news.ycombinator.com - mixed
opencode, pretty good setup out of the box, no need to go through and find packages for the basics like pi
Hacker News comment · 23 Sept 2026 · news.ycombinator.com - positive
Pi runs on just four tools
Hacker News comment · 18 Feb 2026 · news.ycombinator.com - positive
Second, my pi-coding-agent feels smarter.
r/ClaudeCode · — · search snippet · unverified · reddit.com
Pricing
As published, checked 26 Sept 2026.
| Plan | Price | Notes |
|---|---|---|
| Open source | Free | MIT; pay your own model provider. |
Recent changes
Ranked alongside
Other ranked entries in Coding agents.
OpenCodeAnomaly75
Claude CodeAnthropic73
Zed (Agent Panel)Zed Industries73
GitHub CopilotGitHub (Microsoft)72
Codex (CLI and app)OpenAI71
Sources
Every figure above traces to one of these, observed up to 26 Sept 2026.