sandvault: Instructions file for Codex

AGENTS.md

sandvault AGENTS.md is an instructions file for Codex, OpenCode from webcoyote/sandvault. It costs 37 tokens per session, scanned A, original, Apache-2.0.

A project guide for sandvault that includes a required validation command for changes.

In plain words
What is it for?
Use it to follow the project’s testing process and run ./scripts/validate after making changes.
Why use it?
It tells the coding assistant how to check its work before reporting completion.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions AGENTS.md.

This is webcoyote/sandvault's own configuration. It tells Codex and OpenCode how to work on sandvault 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 sandvault configures →

Reuse

Borrowing it

Nothing to install: this file belongs to webcoyote/sandvault. 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/webcoyote/sandvault/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/webcoyote/sandvault

Made for: Codex, OpenCode.

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 sandvault AGENTS.md

README.md
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Your own site
<a href="https://agentmods.dev/instructions/webcoyote/sandvault/agents-md"><img src="https://agentmods.dev/badge/instructions/webcoyote/sandvault/agents-md/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.

agentmods 80×15 button for sandvault AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/webcoyote/sandvault/agents-md"><img src="https://agentmods.dev/badge/instructions/webcoyote/sandvault/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 37 This file is loaded in full into every session.
When invoked 37 The same file — it is already loaded in full.
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 $0.00037 $0.00037
Opus 5.5 $0.00015 $0.00015
Sonnet 5.5 $0.00007 $0.00007
Haiku 4.5 $0.00004 $0.00004

Measured 1mo ago against content hash f119e25c4926, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

sandvault AGENTS.md 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 1mo 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.

AGENTS.md · 7 lines

What it actually says

AGENTS.md

Testing

When making changes always run ./scripts/validate before responding. Report it's results in your response. If you could not run them, explain why.

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. 1mo ago First seen · 7 lines · 37 tokens per session scan A f119e25c4926

Subscribe to this mod's changes

sandvault AGENTS.md is an instructions file published in the GitHub repository webcoyote/sandvault (445 stars, last pushed 11d ago), licensed Apache-2.0. It adds 37 tokens to every session, about $0.0001 per session on Opus 5.5. 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.

Related

Other instructions, from other repositories