spec-drift

spec-drift is a skill for Claude Code, Codex from orin-dx/agent-plugins. It costs 126 tokens per session (380 once invoked), scanned A, original, MIT.

A skill for comparing implemented code with its original software specification. It reads the specification and the implementation to check for differences over time.

In plain words
What is it for?
Use it to check whether an older implementation still matches a spec@1 document.
Why use it?
It helps find specification drift, where code gradually stops matching the requirements it was built from.

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/orin-dx/agent-plugins/spec-drift
Any agent
npx skills add orin-dx/agent-plugins --skill spec-drift
Clone the repo
git clone --depth 1 https://github.com/orin-dx/agent-plugins

Made for: Claude Code, Codex.

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 spec-drift

README.md
[![agentmods](https://agentmods.dev/badge/skills/orin-dx/agent-plugins/spec-drift.svg)](https://agentmods.dev/skills/orin-dx/agent-plugins/spec-drift)
Your own site
<a href="https://agentmods.dev/skills/orin-dx/agent-plugins/spec-drift"><img src="https://agentmods.dev/badge/skills/orin-dx/agent-plugins/spec-drift.svg" alt="Measured on agentmods" height="20"></a>
Per session 126 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 380 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 $0.00126 $0.00380
Opus 5 $0.00063 $0.00190
Sonnet 5 $0.00025 $0.00076
Haiku 4.5 $0.00013 $0.00038

Measured 3d ago against content hash 3f1dbc2c2035, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

spec-drift 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 3d 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.

plugins/scribe/skills/spec-drift/SKILL.md · 28 lines

What it actually says

Scribe — Spec Drift

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. 3d ago First seen · 28 lines · 126 tokens per session scan A 3f1dbc2c2035

Subscribe to this mod's changes

spec-drift is a skill published in the GitHub repository orin-dx/agent-plugins (1 stars, last pushed yesterday), licensed MIT. It adds 126 tokens to every session and 380 once invoked, about $0.0006 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.