bubbuild/bub is a small Python runtime for building AI agents that work in shared environments such as conversations with people. It provides a hook-based turn pipeline and runs agents across command-line, Telegram, and other channels, with built-in tools, skills, and model execution; the catalogue entries extend or configure that workflow.
Borrowing it
Nothing to install: this file belongs to bubbuild/bub. 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/bubbuild/bub/main/AGENTS.mdgit clone --depth 1 https://github.com/bubbuild/bubWrote 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/bubbuild/bub/agents-md)<a href="https://agentmods.dev/instructions/bubbuild/bub/agents-md"><img src="https://agentmods.dev/badge/instructions/bubbuild/bub/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/bubbuild/bub/agents-md"><img src="https://agentmods.dev/badge/instructions/bubbuild/bub/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 | $0.01141 | $0.01141 |
| Opus 5.5 | $0.00456 | $0.00456 |
| Sonnet 5.5 | $0.00228 | $0.00228 |
| Haiku 4.5 | $0.00114 | $0.00114 |
Grade A, and why
bub 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 18d 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 — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Repository Guidelines
Project Structure & Module Organization
Core code lives under src/:
src/bub/__main__.py: Typer CLI entrypoint;main(thebubscript) checks theappextra before importing the CLI.src/bub/core/: agent kernel with no settings or plugin dependencies: agent loop over a tape store (agent.py), model protocol and Republic chat model adapter (model.py), agent events and their bus (events.py), the tape recorder handler (recorder.py), system prompt sections (system_prompt.py), command prompts (commands.py), tools, tape, store, tape context, and code mode (codemode/:CodeMode, therun_codesubprocess runner, and therepublicbridge).src/bub/framework.py: turn orchestration and outbound routing.src/bub/hooks/: hook specifications, execution helpers, interception contracts, andAgentPlugins(agent.py), which connects the agent-loop hooks to anybub.core.Agentthrough its events.src/bub/channels/: channel bases, routing contracts, admission policy, and lifecycle manager.src/bub/{envelope,turn,streaming,errors,model_selection}.py: small kernel vocabulary owned by each concern.src/bub/builtin/: builtin runtime:BubAgent(abub.core.Agentsubclass adding settings, skills, commands, steering),BubModel, tape archiving, CLI wiring, tools, tape services, and the fuzzy-searching file tape store.src/bub/channels/: channel abstractions plus CLI and Telegram adapters.src/bub/skills.py/src/bub/core/tools.py: skill discovery and tool registry.src/skills/: bundled skills shipped with Bub.
Tests live in tests/. The website and docs runtime lives in website/.
Packaging: pip install bub installs only the kernel's dependencies (republic, pydantic, loguru, typing-extensions). Everything outside bub.core (framework, CLI, channels, hooks, skills, builtin) needs the app extra, and the bub script (bub.__main__:main) asks for it when it is missing. Add new non-kernel dependencies to app, not to dependencies.
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.
- 18d ago Changed · +3 lines · +316 tokens per session 140816bd9ef0
- 2mo ago First seen · 64 lines · 825 tokens per session scan A 9cbe896c37fa
bub AGENTS.md is an instructions file published in the GitHub repository bubbuild/bub (1,698 stars, last pushed yesterday), licensed Apache-2.0. It adds 1,141 tokens to every session, about $0.0046 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.
bub AGENTS.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| bub AGENTS.mdbubbuild/bub | Instructions file | 1.7k | yesterday | Apache-2.0 | A | 1,141 | Codex, OpenCode |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | 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 | today | MIT | A | 4,680 | Codex, OpenCode |
| vscode oss-third-party-notices.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 5,516 | GitHub Copilot |
| vscode copilot-instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 3,093 | GitHub Copilot |
| deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness | Instructions file | 274k | 2d ago | MIT | A | 4,313 | Codex, OpenCode |