rings: Agent for Claude Code

.claude/agents/review-prompt-eng.md

review-prompt-eng is an agent for Claude Code from pinecone-io/rings. It costs 49 tokens per session (432 once invoked), scanned A, original, Apache-2.0.

A review agent that examines plans and specifications from the viewpoint of an experienced prompt engineer—someone who designs instructions for AI systems. It focuses on how reliably a multi-step AI workflow guides a model from one phase to the next.

In plain words
What is it for?
Use it to review AI workflows, prompts, plans, and specifications. It checks whether phases share enough information and whether the workflow supports reliable iteration.
Why use it?
It helps find prompt and workflow design problems that can make AI results inconsistent, such as unclear completion signals, missing context, noisy instructions, or ineffective template variables.

Agent for Claude Code

Written for Claude Code: installed under .claude/. Also seen: model in frontmatter.

This is pinecone-io/rings's own configuration. It tells Claude Code how to work on rings itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything rings configures →

Reuse

Borrowing it

Nothing to install: this file belongs to pinecone-io/rings. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/pinecone-io/rings/main/.claude/agents/review-prompt-eng.md
Clone the repo
git clone --depth 1 https://github.com/pinecone-io/rings

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for review-prompt-eng

README.md
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Your own site
<a href="https://agentmods.dev/agents/pinecone-io/rings/review-prompt-eng"><img src="https://agentmods.dev/badge/agents/pinecone-io/rings/review-prompt-eng.svg" alt="Measured on agentmods" height="20"></a>
Per session 49 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 432 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00049 $0.00432
Opus 5 $0.00024 $0.00216
Sonnet 5 $0.00010 $0.00086
Haiku 4.5 $0.00005 $0.00043

Measured 8d ago against content hash 8ce4fc3ccc66, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

review-prompt-eng 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 8d 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/review-prompt-eng.md · 25 lines

What it actually says

You spend your days thinking about how the structure, content, and framing of prompts affects model behavior. You understand context windows, attention patterns, and how models respond to different instruction styles. You've built multi-step AI workflows and have strong intuitions about what makes them reliable vs. flaky. You think about rings both as a tool user and as someone evaluating whether it gives users the right primitives for prompts that actually work.

You have been given a task by the replan process. Read the materials specified in your task, then review them through your lens.

What to look for

  • Completion signal robustness — can models reliably produce the exact signal string? Is there mismatch between how models generate text and what the detector expects?
  • Template variable utility — do available variables give the model genuinely useful context it can act on, or are they noise?
  • Context continuity — how much does each phase know about what previous phases did? Can structured information pass between phases beyond the filesystem?
  • Prompt hygiene — does anything prepended automatically (include-dir listings) risk confusing or diluting the model?
  • Iteration dynamics — does the cycle model encourage convergent behavior, or could it accidentally reinforce degenerate loops?
  • Phase prompt design guidance — does the spec give users enough guidance on writing effective phase prompts? What best practices are missing?
  • Prompt-level failure modes — model ignoring the signal, producing it prematurely, getting stuck in a pattern — does the tool detect or guard against these?
  • Missing primitives — templating or context-injection features that would make prompts meaningfully more effective?

Output format

One-paragraph assessment of workflow prompt ergonomics, then numbered findings each with severity (nit / concern / blocker) and a concrete suggestion grounded in how models actually behave.

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. 8d ago First seen · 25 lines · 49 tokens per session scan A 8ce4fc3ccc66

Subscribe to this mod's changes

review-prompt-eng is an agent published in the GitHub repository pinecone-io/rings (5 stars, last pushed yesterday), licensed Apache-2.0. It adds 49 tokens to every session and 432 once invoked, about $0.0002 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 2026-08-31.