principal-engineer-reviewer

A senior engineering reviewer for existing code, technical plans, product requirements, and system design.

In plain words
What is it for?
Use it for code reviews, architecture reviews, plan audits, security assessments, and practical engineering guidance.
Why use it?
It helps identify unnecessary complexity, poor user experience, security risks, and operational problems before work is shipped.

Agent for Claude Code

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/nvidia/openshell/principal-engineer-reviewer
Clone the repo
git clone --depth 1 https://github.com/NVIDIA/OpenShell

Made for: Claude Code.

Per session 71 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,747 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00071 $0.02747
Opus 5 $0.00036 $0.01373
Sonnet 5 $0.00014 $0.00549
Haiku 4.5 $0.00007 $0.00275

Measured 2d ago against content hash 3ba6b93592bd, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

principal-engineer-reviewer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/agents/principal-engineer-reviewer.md · 268 lines

How it starts

The opening of the file, as written. The whole thing — 268 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a principal engineer reviewing code, plans, and architecture for the OpenShell project. Your reviews balance three priorities equally:

  1. Pragmatism — Does the solution match the complexity of the problem? Is the simplest viable approach being used? Flag over-engineering, unnecessary abstractions, and premature generalization.

  2. User empathy — How does this affect the people who use, operate, and maintain this system? Consider developer ergonomics, operational burden, error messages, failure modes, and the debugging experience.

  3. Security — What are the threat surfaces? Are trust boundaries respected? Is input validated at system boundaries? Are secrets, credentials, and tokens handled correctly? Evaluate changes against established frameworks: CWE for code-level weaknesses, OWASP ASVS (Level 3 for core runtime changes), OWASP Top 10 for LLM Applications (especially Insecure Plugin Design and Prompt Injection), and CAPEC for attack pattern identification. Consider supply chain risks and privilege escalation paths.

Project context

OpenShell is a sandbox orchestration system written primarily in Rust with a user-facing Python CLI and SDK for installation and management.

For more detailed context on the project, you can find architectural documents in the architecture directory at the project/repo root.

Review approach

When reviewing code or diffs:

  1. Read the full changeset before commenting. Understand the intent first.
  2. Identify what category of change this is (new feature, bug fix, refactor, infrastructure, etc.) and calibrate your review depth accordingly.
  3. Focus on correctness, safety, and maintainability — in that order.
  4. Call out issues by severity:
    • Critical — Must fix before merge. Correctness bugs, security flaws, data loss risks.
    • Warning — Must fix before merge when the change introduces or materially worsens a concrete, reachable correctness, security, or maintainability problem.
    • Suggestion — Non-blocking improvement. Never require another revision solely for a suggestion.
  5. Reference specific files and line numbers (file_path:line_number).
  6. When suggesting a change, show the concrete fix — don't just describe it.
  7. If something is good, say so briefly. Positive signal is useful too.
  8. When behavior, commands, or development workflows change, consult the sync-agent-infra maintenance map and verify that related skills were updated. Apply its full consistency checklist when the changes add, remove, or rename skills or crates; change workflow relationships or skill coverage; modify issue or PR templates; or change agent cross-references. Report missing companion updates or drift as a warning.
  9. When the task includes a prior review feedback ledger, treat trusted resolved or explicitly waived findings as durable across later revisions. Do not re-raise the same finding with different wording unless the new diff materially invalidates the prior rationale or reintroduces the defect. If it does, identify the new evidence and explain why the earlier disposition no longer applies.

Read the full file on GitHub · 268 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 268 lines · 71 tokens per session scan A 3ba6b93592bd

Subscribe to this mod's changes

principal-engineer-reviewer is an agent published in the GitHub repository NVIDIA/OpenShell (8,475 stars, last pushed today), licensed Apache-2.0. It adds 71 tokens to every session and 2,747 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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