ArtifactFS is a Git-backed filesystem driver that mounts repositories as local working trees and fetches file contents only when they are needed. It serves agents, sandboxes, containers, and other short-lived environments where waiting for a complete clone slows startup. The catalogue add-ons operate ArtifactFS or support workflows around it.
Borrowing it
Nothing to install: this file belongs to cloudflare/artifact-fs. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/cloudflare/artifact-fs/main/AGENTS.mdgit clone --depth 1 https://github.com/cloudflare/artifact-fsWrote 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.
[](https://agentmods.dev/instructions/cloudflare/artifact-fs/agents-md)<a href="https://agentmods.dev/instructions/cloudflare/artifact-fs/agents-md"><img src="https://agentmods.dev/badge/instructions/cloudflare/artifact-fs/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.
<a href="https://agentmods.dev/instructions/cloudflare/artifact-fs/agents-md"><img src="https://agentmods.dev/badge/instructions/cloudflare/artifact-fs/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00821 | $0.00821 |
| Opus 5.5 | $0.00328 | $0.00328 |
| Sonnet 5.5 | $0.00164 | $0.00164 |
| Haiku 4.5 | $0.00082 | $0.00082 |
Grade A, and why
artifact-fs 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 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.
How it starts
The opening of the file, as written. The whole thing — 47 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Repository-specific guidance for artifact-fs.
Code review rules
- Flag credentials in Git CLI arguments or unredacted logs. Pass credentials through the environment-based helper in
internal/gitstore/gitstore.go, and redact log output withauth.RedactString. - Flag blob bytes converted to
string. KeepBlobToCachebinary-safe by streaminggit cat-file --batchoutput to disk. - Keep
GIT_NO_LAZY_FETCH=1ongit cat-file --batch-checkinbatchResolveSizes. Removing it turns size resolution in blobless clones into network round-trips. - Normalize paths only with
model.CleanPath(). Do not add local wrappers. - Use the canonical
model.*interfaces for snapshot, overlay, hydrator, and gitstore access. Do not add subset interfaces around them.
Architecture
cmd/artifact-fsis the only binary entrypoint.internal/cliwires commands ontodaemon.Service.internal/daemonowns repo lifecycle: registry sync, snapshot publish, overlay reconcile, FUSE mount, watcher, refresh loop.internal/fusefsis the merged view and writable filesystem layer.internal/gitstoreis the performance-sensitive git wrapper; most easy-to-break invariants live there.internal/snapshotandinternal/overlayare persistent SQLite-backed stores.
Runtime contracts
ARTIFACT_FS_ROOTis the state root.artifact-fs daemon --rootis the mount root. They are different things.add-repois one-shot by default: register repo, clone blobless, build the initial snapshot, then exit. It does not mount FUSE or start background goroutines.add-repo --asynconly registers prepare state. The daemon mounts a gated placeholder, prepares clone/fetch and snapshot in the background, then opens the gate and starts watcher/refresh.daemonis long-running: it mounts registered repos and starts watcher, refresh, and hydrator workers.git.CloneBloblessalready populates the git index withread-tree HEAD; be careful about extra index resets because they can discard staged state.
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 · 47 lines · 821 tokens per session scan A 6a50da478d04
artifact-fs AGENTS.md is an instructions file published in the GitHub repository cloudflare/artifact-fs (1,207 stars, last pushed 8d ago), licensed Apache-2.0. It adds 821 tokens to every session, about $0.0033 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.
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