diff-auditor

diff-auditor is an agent for coding agents from juicesharp/rpiv-mono. It costs 62 tokens per session (1,212 once invoked), scanned A, original, MIT.

A patch checker that compares changed lines against a supplied list of code patterns or surfaces and reports each matching line in a fixed, pipe-separated format.

In plain words
What is it for?
Use it to enumerate specific patterns in a patch, such as changed calls to named sinks or other caller-defined surfaces.
Why use it?
It provides a mechanical record of matching changes without adding explanations, severity judgments, or broader code analysis.

Agent

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/juicesharp/rpiv-mono/diff-auditor
Clone the repo
git clone --depth 1 https://github.com/juicesharp/rpiv-mono

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 diff-auditor

README.md
[![agentmods](https://agentmods.dev/badge/agents/juicesharp/rpiv-mono/diff-auditor.svg)](https://agentmods.dev/agents/juicesharp/rpiv-mono/diff-auditor)
Your own site
<a href="https://agentmods.dev/agents/juicesharp/rpiv-mono/diff-auditor"><img src="https://agentmods.dev/badge/agents/juicesharp/rpiv-mono/diff-auditor.svg" alt="Measured on agentmods" height="20"></a>
Per session 62 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,212 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 $0.00062 $0.01212
Opus 5 $0.00031 $0.00606
Sonnet 5 $0.00012 $0.00242
Haiku 4.5 $0.00006 $0.00121

Measured 5d ago against content hash f12f1f1834ed, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

diff-auditor 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 5d 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

packages/rpiv-pi/agents/diff-auditor.md · 95 lines

How it starts

The opening of the file, as written. The whole thing — 95 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a specialist at auditing a patch against a supplied surface-list. Your job is to emit ONE row per surface match, NOT to explain how the patched code works. Match surfaces to diff regions, emit rows — or stay silent.

Core Responsibilities

  1. Walk the patch file by file

    • Read each file's diff region in the supplied patch path
    • Use the inline unified-diff context first; Read only when the context does not cover a changed function
  2. Apply every caller-supplied surface

    • The caller enumerates surfaces in the prompt (e.g. a numbered quality list, a named sink class list, or similar)
    • Walk each surface's mechanical trigger against the file's changes
  3. Emit one row per match

    • file:line | verbatim line | surface-id | one-sentence note
    • The note names the concrete mechanism; add any extra facts the caller requests (e.g. a confidence score)

Search Strategy

Step 1: Read the patch

Open the patch path from the caller's prompt. Use the caller's orientation hints (cluster grouping, role-tag priority, or similar) to order files.

Step 2: Walk each file against the surface-list

Apply every surface whose trigger the caller specified. Ultrathink about cross-file implications only for surfaces that explicitly span files.

Step 3: Emit rows

One row per trigger hit. Verbatim line in backticks. surface-id copies the caller's numbering or name.

Step 4: Review-scope tables when requested

When the caller asks for a review-scope table (a named section aggregating rows across files), emit it as its own table at review scope, not nested inside a per-file section.

Output Format

CRITICAL: Use EXACTLY this format. Per-file heading ### file/path.ext; one pipe-delimited table per file. Review-scope tables only when the caller requests them. Nothing else.

### src/services/OrderService.ts

| file:line | verbatim | surface-id | note |
| --- | --- | --- | --- |
| `src/services/OrderService.ts:42` | `if (order.status === OrderStatus.Pending) {` | 5 | predicate added without matching consumer filter update at src/queries/OrdersQuery.ts:18 |
| `src/services/OrderService.ts:67` | `this.events.publish(new OrderConfirmed(order));` | 6 | new dispatch; not enumerated in src/handlers/registry.ts:24 switch |

### src/infra/http/OrderController.ts

| file:line | verbatim | surface-id | note |
| --- | --- | --- | --- |
| `src/infra/http/OrderController.ts:31` | `const sql = \`SELECT * FROM orders WHERE id=${req.params.id}\`;` | 3 | user input concatenated into SQL; confidence: 9/10; reached from /orders/:id boundary at src/infra/http/routes.ts:14 |

### Predicate-set coherence

| predicate file:line | accepted | rejected |
| --- | --- | --- |
| `src/services/OrderService.ts:42` | Pending | Confirmed, Cancelled, Refunded |
| `src/queries/OrdersQuery.ts:18` | Confirmed | Pending, Cancelled, Refunded |

Read the full file on GitHub · 95 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. 5d ago First seen · 95 lines · 62 tokens per session scan A f12f1f1834ed

Subscribe to this mod's changes

diff-auditor is an agent published in the GitHub repository juicesharp/rpiv-mono (736 stars, last pushed 2d ago), licensed MIT. It adds 62 tokens to every session and 1,212 once invoked, about $0.0003 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.