Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add instructions/home-assistant/core/copilot-instructionsgit clone --depth 1 https://github.com/home-assistant/coreWhat 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 | $0.02557 | $0.02557 |
| Opus 5 | $0.01278 | $0.01278 |
| Sonnet 5 | $0.00511 | $0.00511 |
| Haiku 4.5 | $0.00256 | $0.00256 |
Grade C, and why
core copilot-instructions.md scanned grade C with 2 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 today.
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.
Downloads and executes remote codehighSupply chain
curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.
- When entering a new environment or worktree, run `script/setup` to set up the virtual environment with all development dependencies (pylint, pre-commit hooks, etc.). This is required before committing. If uv reports th Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
- When entering a new environment or worktree, run `script/setup` to set up the virtual environment with all development dependencies (pylint, pre-commit hooks, etc.). This is required before committing. If uv reports th Copies of this mod
1 near-identical copy found in the catalogue:
- core AGENTS.md — 86% identical, 137 lines differ
How it starts
The opening of the file, as written. The whole thing — 194 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Copilot code review instructions
- Start review comments with a short, one-sentence summary of the suggested fix.
- Do not comment on code style, formatting or linting issues.
- Flag comments that over-explain straightforward code, narrate the obvious, or read like AI commentary (multi-sentence justifications for a single line).
- A Pull Request with a dependency version bump should only contain changes required for the version bump. If the PR includes other changes, request that they are removed from the PR.
- Check that the PR description is complete and filled in according to the PR template included below. Every section and checklist item from the template must be present, except the
## Breaking changesection which is optional. No content from the template should be missing, except for HTML comments and Markdown link reference definitions (lines of the form[name]: url), which do not render and cannot be verified from the description. Even unchecked checkboxes or empty sections must be present. This is a hard requirement.
Pull Request template
The PR description must follow this template (from .github/PULL_REQUEST_TEMPLATE.md):
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You are amazing! Thanks for contributing to our project!
Please, DO NOT DELETE ANY TEXT from this template! (unless instructed).
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## Breaking change
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If your PR contains a breaking change for existing users, it is important
to tell them what breaks, how to make it work again and why we did this.
This piece of text is published with the release notes, so it helps if you
write it towards our users, not us.
Note: Remove this section if this PR is NOT a breaking change.
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## Proposed change
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## Type of change
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- [ ] Dependency upgrade
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## Additional information
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- This PR is related to issue:
- Link to documentation pull request:
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## Checklist
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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.
- today First seen · 194 lines · 2,557 tokens per session scan C 288b26df9d09
core copilot-instructions.md is an instructions file published in the GitHub repository home-assistant/core (90,198 stars, last pushed today), licensed Apache-2.0. It adds 2,557 tokens to every session, about $0.0128 per session on Opus 5. A static security scan graded it C with 2 findings (downloads and executes remote code, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other instructions, from other repositories
Gladys AGENTS.md
Instructions for GladysAssistant/Gladys, covering agents.md, cursor cloud specific instructions, running the app (dev mode), non-obvious caveats and feature specs (spec-first process).
meshcore-mqtt AGENTS.md
AGENTS.md instructions for ipnet-mesh/meshcore-mqtt, covering meshcore mqtt bridge - opencode context, instructions for opencode, project overview, key features and architecture.
meshcore-mqtt CLAUDE.md
Claude Code instructions for ipnet-mesh/meshcore-mqtt, a project described as: MeshCore MQTT Bridge (Companion App over Serial/BLE/TCP).
iot-dc3 AGENTS.md
AGENTS.md instructions for pnoker/iot-dc3, covering agents.md, scope and precedence, sources of truth, project overview and repository map.
iot-dc3 CLAUDE.md
Claude Code instructions for pnoker/iot-dc3: This file provides guidance to AI coding assistants when working with code in this repository.
AetherEdge AGENTS.md
Instructions for EvanL1/AetherEdge, covering aetheredge agent instructions, product direction, repository map, architecture boundaries and ai safety.