patch-verification

A checklist for checking a code change after it has been applied. It reviews the diff, syntax, imports, documentation strings, templates, hooks, and runtime logic.

In plain words
What is it for?
Use it after modifying a codebase, especially when the change affects Python files, agent tools, templates, or hooks.
Why use it?
It helps catch crashes, missing dependencies, invalid tool descriptions, and other mistakes before the change is committed or used.

Skill for Claude CodeCodex

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 skills/microsoft/autosaddler/patch-verification
Any agent
npx skills add microsoft/AutoSaddler --skill patch-verification
Clone the repo
git clone --depth 1 https://github.com/microsoft/AutoSaddler

Made for: Claude Code, Codex.

Per session 38 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 974 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 $0.00038 $0.00974
Opus 5 $0.00019 $0.00487
Sonnet 5 $0.00008 $0.00195
Haiku 4.5 $0.00004 $0.00097

Measured 2d ago against content hash 38518d33a4ba, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

patch-verification 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.

src/autosaddler/v1/proposer/autosaddler/skills/patch-verification/SKILL.md · 126 lines

How it starts

The opening of the file, as written. The whole thing — 126 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Patch Verification

Overview

A patch that crashes or introduces bugs at runtime is worse than no patch at all. Every patch must pass thorough verification before being committed.

Only fix what would actually crash or produce incorrect behavior — do NOT change the patch's intent.

When to Use

After applying ANY patch type (capability or steering).

Verification Procedure

Step 1: Review the Diff

git diff
  • Does the diff match your intent? No unintended changes?
  • Are there leftover debug statements, commented-out code, or TODOs?
  • Are there any files modified that should not have been changed?

Step 2: Syntax and Import Check

For every modified Python file:

python3 -m py_compile <modified_file>
python3 -c "import <modified_module>"
  • No SyntaxError, IndentationError, or TabError
  • No ImportError or ModuleNotFoundError
  • No NameError from undefined variables or functions at module level

Step 3: Docstring Integrity

Docstrings are the agent's only interface to tools — errors here directly cause agent failures.

  • No placeholder values ([...], {...}, <placeholder>) — these crash downstream parsers
  • All examples use concrete, valid values
  • Parameter names in the docstring match the actual method signature
  • Return value description matches what the implementation actually returns
  • No stale documentation from copy-paste (e.g., wrong tool name, wrong parameter list from another method)
  • No literal escape sequences (\n, \t, etc.) used to represent multi-line examples or formatting inside docstrings — these produce actual control characters in the parsed string and can cause SyntaxError or silently corrupt the docstring text. Use triple-quoted strings with real newlines instead

Step 4: Template String Safety

If the patch modifies any string that uses .format() or f-string interpolation:

  • Every {placeholder} has a corresponding .format() argument
  • No extra or missing placeholders from copy-paste
  • No unescaped curly braces in literal text (use {{ and }} to escape)
  • No cross-file contamination between template variables

Read the full file on GitHub · 126 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 · 126 lines · 38 tokens per session scan A 38518d33a4ba

Subscribe to this mod's changes

patch-verification is a skill published in the GitHub repository microsoft/AutoSaddler (150 stars, last pushed 7d ago), licensed MIT. It adds 38 tokens to every session and 974 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 2026-08-30.

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