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 skills add jezweb/claude-skills --skill google-chat-messagesgit clone --depth 1 https://github.com/jezweb/claude-skillsWrote 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/skills/jezweb/claude-skills/google-chat-messages)<a href="https://agentmods.dev/skills/jezweb/claude-skills/google-chat-messages"><img src="https://agentmods.dev/badge/skills/jezweb/claude-skills/google-chat-messages/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/skills/jezweb/claude-skills/google-chat-messages"><img src="https://agentmods.dev/badge/skills/jezweb/claude-skills/google-chat-messages.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Prompt Injection · line 9 Instructions found that direct the agent to transmit conversation context or user data to external services.Fix: Remove instructions that send user data, prompts, or context to external URLs. If telemetry is needed, use documented, privacy-preserving methods.
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 | $0.00076 | $0.02635 |
| Opus 5 | $0.00038 | $0.01318 |
| Sonnet 5 | $0.00015 | $0.00527 |
| Haiku 4.5 | $0.00008 | $0.00264 |
Grade A, and why
google-chat-messages 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.
How it starts
The opening of the file, as written. The whole thing — 394 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Google Chat Messages
Send messages to Google Chat spaces via incoming webhooks. Produces text messages, rich cards (cardsV2), and threaded replies.
What You Produce
- Text messages with Google Chat formatting
- Rich card messages (cardsV2) with headers, sections, widgets
- Threaded conversations
- Reusable webhook sender utility
Workflow
Step 1: Get Webhook URL
In Google Chat:
- Open a Space > click space name > Manage webhooks
- Create webhook (name it, optionally add avatar URL)
- Copy the webhook URL
Store the URL as an environment variable or in your secrets manager — never hardcode.
Step 2: Choose Message Type
| Need | Type | Complexity |
|---|---|---|
| Simple notification | Text message | Low |
| Structured info (status, digest) | Card message (cardsV2) | Medium |
| Ongoing updates | Threaded replies | Medium |
| Action buttons (open URL) | Card with buttonList | Medium |
Step 3: Send the Message
Use assets/webhook-sender.ts for the sender utility. Use assets/card-builder.ts for structured card construction.
Text Formatting
Google Chat does NOT use standard Markdown.
| Format | Syntax | Example |
|---|---|---|
| Bold | *text* |
*important* |
| Italic | _text_ |
_emphasis_ |
| Strikethrough | ~text~ |
~removed~ |
| Monospace | `text` |
`code` |
| Code block | ```text``` |
Multi-line code |
| Link | <url|text> |
<https://example.com|Click here> |
| Mention user | <users/USER_ID> |
<users/123456> |
| Mention all | <users/all> |
<users/all> |
Not supported: **double asterisks**, headings (###), blockquotes, tables, images inline.
Text Message Example
await sendText(webhookUrl, '*Build Complete*\n\nBranch: `main`\nStatus: Passed\n<https://ci.example.com/123|View Build>');
cardsV2 Structure
Cards use the cardsV2 format (recommended over legacy cards).
const message = {
cardsV2: [{
cardId: 'unique-id',
card: {
header: {
title: 'Card Title',
subtitle: 'Optional subtitle',
imageUrl: 'https://example.com/icon.png',
imageType: 'CIRCLE' // or 'SQUARE'
},
sections: [{
header: 'Section Title', // optional
widgets: [
// widgets go here
]
}]
}
}]
};
What ships with it
3 files 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.
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.
- 8d ago First seen · 394 lines · 76 tokens per session scan A f78ffc506edb
google-chat-messages is a skill published in the GitHub repository jezweb/claude-skills (1,001 stars, last pushed 2mo ago), licensed MIT. It adds 76 tokens to every session and 2,635 once invoked, about $0.0004 per session on Opus 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 2026-09-03.
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agent-tamagotchi
Terminal pet that lives in your statusline. 12 species, 5 stats (DEBUGGING, PATIENCE, CHAOS, WISDOM, SPEED). Reacts to your workflow - happy when tests pass, sad when builds fail, excited during swarm mode. Deterministic species from user ID.