Borrowing it
Nothing to install: this file belongs to 2youg1/sprawling. 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/2youg1/sprawling/main/AGENTS.mdgit clone --depth 1 https://github.com/2youg1/sprawlingWrote 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/2youg1/sprawling/agents-md)<a href="https://agentmods.dev/instructions/2youg1/sprawling/agents-md"><img src="https://agentmods.dev/badge/instructions/2youg1/sprawling/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/2youg1/sprawling/agents-md"><img src="https://agentmods.dev/badge/instructions/2youg1/sprawling/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 | $0.02019 | $0.02019 |
| Opus 5.5 | $0.00808 | $0.00808 |
| Sonnet 5.5 | $0.00404 | $0.00404 |
| Haiku 4.5 | $0.00202 | $0.00202 |
Grade A, and why
sprawling 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 — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md — how work is done in this repository
For any agent or person about to change this code. Read this file to the end before the first edit; it is short on purpose, and everything it does not cover is one link away.
sprawling is a locally deployed agent-city harness: one Rust binary, a WebAssembly client embedded inside it, and a city that keeps its whole history in one append-only Ledger. Most of it was written by models, and every rule below exists for one reason that applies to a person just as much: a contributor who does not remember yesterday still has to produce work that holds.
The loop
cargo install just cargo-nextest --locked # once; the toolchain installs itself from rust-toolchain.toml
just check # fmt + clippy (-D warnings, --all-features) + nextest + every machine gate
A change is finished when just check is green. "I finished it" is a claim; a green run is the evidence.
| Command | What it does |
|---|---|
just check |
the closing condition for every change |
just gates |
the machine gates alone |
just check-web |
clippy on the wasm target — the two places just check cannot reach |
just build-web |
build the client bundle, without dx |
just dist |
the whole deliverable: client, binary, bill of materials, size badges |
just sim [seed] |
citysim scenarios; a failure reproduces from its seed |
just spec <crate> |
generate a SPEC skeleton |
just api-baseline |
recompute the public-surface baselines |
just replay <log> |
verify a ledger chain offline, read-only |
just mem [pid] / just bench / just budget |
the measurements, in this platform's own vocabulary |
just fuzz <target> / just mutants |
fuzz targets / mutation testing |
Read before you write
ARCHITECTURE.md— what the code is made of, how the twelve crates are wired, what one dispatch does end to end. Itsdepmapblock and module map are machine authorities.- The SPEC of the crate you are touching,
crates/<crate>/<crate>-SPEC.md— the interfaces and decisions, written before the code. docs/glossary.md— one name per concept, enforced by a gate.- The tests next to the code you are about to change.
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 · 100 lines · 2,019 tokens per session scan A 3e0886237ae6
sprawling AGENTS.md is an instructions file published in the GitHub repository 2youg1/sprawling (91 stars, last pushed 2mo ago), licensed MPL-2.0. It adds 2,019 tokens to every session, about $0.0081 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.
sprawling AGENTS.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| sprawling AGENTS.md2youg1/sprawling | Instructions file | 91 | 2mo ago | MPL-2.0 | A | 2,019 | Codex, OpenCode |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 9,719 | GitHub Copilot |
| next.js AGENTS.mdvercel/next.js | Instructions file | 143k | yesterday | MIT | A | 7,461 | Codex, OpenCode |
| langchain AGENTS.mdlangchain-ai/langchain | Instructions file | 149k | yesterday | MIT | A | 4,680 | Codex, OpenCode |
| vscode oss-third-party-notices.instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 5,516 | GitHub Copilot |
| vscode copilot-instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 3,093 | GitHub Copilot |
| deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness | Instructions file | 274k | 2d ago | MIT | A | 4,313 | Codex, OpenCode |