A documentation-update procedure for bringing project instructions and technical documents in line with a code change. It covers agent instructions, design notes, contracts, runbooks, and the README when user-visible behaviour changes.

Use it after a change to review the relevant documentation, update existing sections, and record why constraints exist and what can break without them.

It prevents documentation from describing old behaviour or leaving important design constraints unexplained after code is modified.

How frostyard/snosi configures GitHub Copilot

Reuse

Borrowing it

Nothing to install: this file belongs to frostyard/snosi. 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/frostyard/snosi/main/.github/prompts/update-docs.md

Clone the repo

git clone --depth 1 https://github.com/frostyard/snosi

Made for: GitHub Copilot.

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.

README.md

[![agentmods](https://agentmods.dev/badge/commands/frostyard/snosi/update-docs/github.svg)](https://agentmods.dev/commands/frostyard/snosi/update-docs)

Your own site

<a href="https://agentmods.dev/commands/frostyard/snosi/update-docs"><img src="https://agentmods.dev/badge/commands/frostyard/snosi/update-docs/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/commands/frostyard/snosi/update-docs"><img src="https://agentmods.dev/badge/commands/frostyard/snosi/update-docs.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 362 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.

Model	Per session	Once invoked
Fable 5.1	$0.00000	$0.00362
Opus 5.5	$0.00000	$0.00145
Sonnet 5.5	$0.00000	$0.00072
Haiku 4.5	$0.00000	$0.00036

Measured 2mo ago against content hash db964aac2d5f, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

update-docs 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 2mo 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.

.github/prompts/update-docs.md · 31 lines

What it actually says

Prompt: update documentation after a change

Goal: bring the documentation back in sync with <the change that just landed>.

A task in this repository is not complete until the documentation is reviewed and updated. Work through these, in order:

CLAUDE.md — the operational contract summary an agent reads before any change. Update the section that covers the area you touched. Record why a constraint exists and what breaks without it, not just what the code does.
docs/design/ (formerly yeti/) — written for AI consumption: architecture, patterns, and decision rationale rather than user-facing guides. Update docs/design/overview.md plus the focused file for the area (build-pipeline.md, ci-cd.md, sysexts.md, testing.md).
The rest of docs/ — normative contracts and runbooks (see the index in docs/README.md). Change these only when the contract itself changed, and say so explicitly in the pull request.
README.md — only when a user-visible output, build target, or supported flow changed.

Guidelines:

Prefer amending an existing section over appending a new one; duplicated, drifting descriptions of the same mechanism are worse than none.
Record root causes for bugs that were non-obvious, including the evidence that proved them, so the same investigation is not repeated.
Mark anything unproven as blocked or provisional. Never describe a gate as passing on the strength of a fixture or static check alone.
Do not create new planning or note files; add them only when explicitly requested.

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.

2mo ago First seen · 31 lines · 0 tokens per session scan A db964aac2d5f

Subscribe to this mod's changes

update-docs is a command published in the GitHub repository frostyard/snosi (32 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 362 tokens. 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 2026-09-06.

Writing and docs

update-docs next to 6 commands from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
update-docsfrostyard/snosi	Command	32	today	MIT	A	0	GitHub Copilot
checklistgithub/spec-kit	Command	148k	yesterday	MIT	A	13	Claude Code
clarifygithub/spec-kit	Command	148k	yesterday	MIT	A	27	Claude Code
specifygithub/spec-kit	Command	148k	yesterday	MIT	A	13	Claude Code
analyzegithub/spec-kit	Command	148k	yesterday	MIT	A	26	Claude Code
convergegithub/spec-kit	Command	148k	yesterday	MIT	A	35	Claude Code
implementgithub/spec-kit	Command	148k	yesterday	MIT	A	14	Claude Code

snosi: Command for GitHub Copilot