horizon-cast

horizon-cast is a skill for Claude Code from peters/horizon. It costs 43 tokens per session (184 once invoked), scanned A, original, MIT.

A tool for casting Horizon panels, workspaces, cloud cards, or the main Horizon window to an Apple TV through approved casting controls.

In plain words
What is it for?
It is for finding an Apple TV, pairing with it, starting or stopping an authorized cast, and checking casting status.
Why use it?
It keeps receiver discovery, pairing, status checks, and stopping a cast in one workflow. It also requires permission before sharing an application's screen.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the horizon plugin — 6 skills shipped together

Good fit It is for finding an Apple TV, pairing with it, starting or stopping an authorized cast, and checking casting status.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/peters/horizon/horizon-cast
Install

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.

Any agent
npx skills add peters/horizon --skill horizon-cast
Clone the repo
git clone --depth 1 https://github.com/peters/horizon

Made for: Claude Code.

Or install horizon, the plugin that ships this one along with the rest of its 6 skills.

Wrote 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.

agentmods badge for horizon-cast

README.md
[![agentmods](https://agentmods.dev/badge/skills/peters/horizon/horizon-cast/github.svg)](https://agentmods.dev/skills/peters/horizon/horizon-cast)
Your own site
<a href="https://agentmods.dev/skills/peters/horizon/horizon-cast"><img src="https://agentmods.dev/badge/skills/peters/horizon/horizon-cast/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.

agentmods 80×15 button for horizon-cast

Your own site · 80×15
<a href="https://agentmods.dev/skills/peters/horizon/horizon-cast"><img src="https://agentmods.dev/badge/skills/peters/horizon/horizon-cast.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 184 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00043 $0.00184
Opus 5.5 $0.00017 $0.00074
Sonnet 5.5 $0.00009 $0.00037
Haiku 4.5 $0.00004 $0.00018

Measured 8d ago against content hash cab8002e971d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

horizon-cast 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 8d 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.

assets/plugins/claude-code/skills/horizon-cast/SKILL.md · 18 lines

What it actually says

Horizon casting

Use the public cast tool on the Horizon browser MCP server (--browser-mcp). The calling agent must run in a Horizon workspace on Linux. Read the casting reference before receiver or session operations. Use the current tool schema for arguments. If the tool or supporting host is absent, report the missing capability. Do not use private runtime files or another capture path.

A task to examine casting does not authorize a cast to a real TV. Start, pair, stop, or forget only within the user's requested receiver and task. Application capture needs the person's permission in the Cast picker. An agent cannot grant that permission.

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

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.

  1. 8d ago First seen · 18 lines · 43 tokens per session scan A cab8002e971d

Subscribe to this mod's changes

horizon-cast is a skill published in the GitHub repository peters/horizon (717 stars, last pushed today), licensed MIT. It adds 43 tokens to every session and 184 once invoked, about $0.0002 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 2026-10-09.

Related

Other skills, from other repositories