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 rules/maccman/agent-playground/typescriptgit clone --depth 1 https://github.com/maccman/agent-playgroundWhat 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 | $0.00492 | $0.00492 |
| Opus 5 | $0.00246 | $0.00246 |
| Sonnet 5 | $0.00098 | $0.00098 |
| Haiku 4.5 | $0.00049 | $0.00049 |
Grade A, and why
typescript 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 yesterday.
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.
This is a copy
92% identical to typescript — 5 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
What it actually says
TypeScript
- TypeScript is available under the
tsxcommand. - Use
pnpm installto install dependencies. - Env vars should be loaded from the
.envfile usingdotenv- make sure you useimport { config } from 'dotenv'to load the env vars.
Use TypeScript when TypeScript standard libraries make it best path forward. For example, PDF processing.
Prefer typescript over python for any task that can be done in typescript.
Suggested packages (TypeScript/Node.js):
- PDF Generation:
pdfkit - PDF extraction:
pdf-parseorpdfjs-dist - Data analysis:
danfojs-node(pandas-like DataFrame for Node.js) - CSV reading/writing:
csv-parse,csv-stringify, orpapaparse - Data visualization:
vegaorvega-lite(for programmatic chart generation), orplotly.jsfor interactive charts - OCR: OCR is currently not supported in Node.js/TypeScript (no reliable, maintained package)
- Table/markdown formatting:
cli-table3for console tables,markdown-tablefor Markdown output - Excel:
exceljs - HTML parsing:
cheerio(jQuery-like HTML parsing for Node.js) - Markdown parsing:
marked
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.
- yesterday First seen · 27 lines · 492 tokens per session scan A beedaf3d58d9
typescript is a cursor rule published in the GitHub repository maccman/agent-playground (2 stars, last pushed 6mo ago), licensed MIT. It adds 492 tokens to every session, about $0.0025 per session on Opus 5. A static security scan graded it A with 0 findings. It is 92% identical to typescript, differing in 5 lines, and is treated as a copy.
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