hotpath-rs is a Rust profiler that measures where programs spend time, use CPU and memory, wait on I/O, and perform database, HTTP, or asynchronous operations. Rust developers use it to locate performance bottlenecks and inspect timing, allocation, and async-flow data.
Borrowing it
Nothing to install: this file belongs to pawurb/hotpath-rs. 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/pawurb/hotpath-rs/main/AGENTS.mdgit clone --depth 1 https://github.com/pawurb/hotpath-rsWrote 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/pawurb/hotpath-rs/agents-md)<a href="https://agentmods.dev/instructions/pawurb/hotpath-rs/agents-md"><img src="https://agentmods.dev/badge/instructions/pawurb/hotpath-rs/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/pawurb/hotpath-rs/agents-md"><img src="https://agentmods.dev/badge/instructions/pawurb/hotpath-rs/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 | $0.01911 | $0.01911 |
| Opus 5.5 | $0.00764 | $0.00764 |
| Sonnet 5.5 | $0.00382 | $0.00382 |
| Haiku 4.5 | $0.00191 | $0.00191 |
Grade A, and why
hotpath-rs 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 27d 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 — 101 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
This file provides guidance to AI agent when working with code in this repository.
Project Overview
hotpath-rs is a lightweight, feature-gated Rust profiler that tracks function execution time, memory allocations, channels, streams, futures, locks, SQL queries, HTTP requests, byte-level I/O, and threads. All instrumentation is behind the hotpath Cargo feature: with it off, every macro is a no-op and no dependencies are compiled.
Workspace layout:
crates/hotpath- Main library with profiling runtime, reporting, metrics/MCP servers, and the TUI/CLI binariescrates/hotpath-macros- Procedural macros (#[measure],#[main],#[future_fn], ...)crates/hotpath-drain- Lock-free per-thread SPSC event queues and their registry; re-exported inside hotpath ascrate::batchcrates/test-*- One integration-test crate per instrumented subsystem or third-party integration; the current list is themembersarray in the rootCargo.tomltest-toastyis NOT a workspace member: toasty's rusqlite and the workspace's sqlx-sqlite have conflictinglinks = "sqlite3"values, so it's built viacargo run --manifest-path crates/test-toasty/Cargo.toml ...
crates/hotpath-meta/crates/hotpath-macros-meta/crates/hotpath-drain-meta- Copies of hotpath used to profile the profiler itself (not intended for external use)docs/- mdBook source for the hotpath.rs documentation site (the Axum web server that builds/serves it lives in a separate private repo at../hotpath-backend)
Reference Docs
The dev_docs point to where things are defined in source and record gotchas the code can't show - read them only when a task needs the specifics:
dev_docs/features.md- Where features, macros, the builder API, env vars and cloud code are defined, plus gotchasdev_docs/architecture.md- Background workers, servers, CPU sampling code mapdev_docs/tui.md- TUI build/usage and code mapdev_docs/testing.md- Integration-test patterns. Read before writing or modifying an integration test.CONTRIBUTING.md- Meta-crate mirroring, benchmark commands, samply tracing, local CI check commands, docs build prerequisites
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.
- 27d ago Changed · +38 tokens per session 7397eb1657b8
- 1mo ago Changed · -6 lines · -638 tokens per session f55cc152a138
- 1mo ago Changed · -7 tokens per session 29bcb99455a1
- 1mo ago Changed · +1 lines · +90 tokens per session 7da1199ed62b
- 1mo ago Changed · -83 tokens per session 4ac10b01714f
- 1mo ago Changed · +57 tokens per session 3ad7103124de
- 2mo ago Changed · +2 lines · +118 tokens per session 36999fefbdda
- 2mo ago First seen · 104 lines · 2,336 tokens per session scan A 6db0deb49fa2
hotpath-rs AGENTS.md is an instructions file published in the GitHub repository pawurb/hotpath-rs (1,895 stars, last pushed 19d ago), licensed MIT. It adds 1,911 tokens to every session, about $0.0076 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.
hotpath-rs AGENTS.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| hotpath-rs AGENTS.mdpawurb/hotpath-rs | Instructions file | 1.9k | 19d ago | MIT | A | 1,911 | 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 | today | 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 |