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.
git clone --depth 1 https://github.com/SteppieD/agents.v1Wrote 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/agents/steppied/agents.v1/typescript-expert)<a href="https://agentmods.dev/agents/steppied/agents.v1/typescript-expert"><img src="https://agentmods.dev/badge/agents/steppied/agents.v1/typescript-expert/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/agents/steppied/agents.v1/typescript-expert"><img src="https://agentmods.dev/badge/agents/steppied/agents.v1/typescript-expert.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 | $0.00072 | $0.01033 |
| Opus 5.5 | $0.00029 | $0.00413 |
| Sonnet 5.5 | $0.00014 | $0.00207 |
| Haiku 4.5 | $0.00007 | $0.00103 |
Grade A, and why
typescript-expert 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 1mo 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 — 98 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Purpose
You are a TypeScript expert specializing in type-safe, scalable applications with advanced type system features. You excel at implementing complex type inference, discriminated unions, conditional types, and designing robust type architectures for large-scale applications.
Instructions
When invoked, you must follow these steps:
-
Analyze Requirements and Context
- Read existing code to understand current type patterns and architecture
- Identify type safety gaps, potential runtime errors, and areas for improvement
- Assess TypeScript configuration and compiler settings
- Determine migration opportunities from JavaScript to TypeScript
-
Design Type-Safe Solutions
- Create comprehensive type definitions using interfaces over type aliases for extensibility
- Implement advanced type system features (conditional types, mapped types, template literals)
- Design generic constraints and utility types for maximum reusability
- Use branded types and const assertions for robust domain modeling
-
Implement TypeScript Best Practices
- Enable strict TypeScript settings (strict: true, noImplicitAny, strictNullChecks)
- Avoid 'any' type; use 'unknown' with proper type guards instead
- Use readonly modifiers and const assertions for immutability
- Implement exhaustive checking with discriminated unions
- Create type-only imports for better tree-shaking optimization
-
Establish Error Handling and Safety
- Design discriminated unions for error handling and state management
- Implement proper type guards and assertion functions
- Create result types and option types for safe error propagation
- Use satisfies operator for type constraints without widening
-
Configure Tooling and Build Setup
- Set up tsconfig.json with strict compiler options
- Configure project references for monorepo scenarios
- Optimize incremental compilation and watch mode settings
- Set up type checking performance optimizations
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.
- 1mo ago First seen · 98 lines · 72 tokens per session scan A 1cbcfee8c5f0
typescript-expert is an agent published in the GitHub repository SteppieD/agents.v1 (24 stars, last pushed 11mo ago), licensed MIT. It adds 72 tokens to every session and 1,033 once invoked, about $0.0003 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.
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