Borrowing it
Nothing to install: this file belongs to reasvyn/docsgrep. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/reasvyn/docsgrep/main/.agents/skills/code-writing/SKILL.mdgit clone --depth 1 https://github.com/reasvyn/docsgrepWrote 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/reasvyn/docsgrep/code-writing)<a href="https://agentmods.dev/skills/reasvyn/docsgrep/code-writing"><img src="https://agentmods.dev/badge/skills/reasvyn/docsgrep/code-writing/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/reasvyn/docsgrep/code-writing"><img src="https://agentmods.dev/badge/skills/reasvyn/docsgrep/code-writing.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 | $0.00021 | $0.00542 |
| Opus 5.5 | $0.00008 | $0.00217 |
| Sonnet 5.5 | $0.00004 | $0.00108 |
| Haiku 4.5 | $0.00002 | $0.00054 |
Grade A, and why
code-writing 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 2mo 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 — 61 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Before writing code
- Read
AGENTS.mdfor repo conventions. - Find an existing tool handler that does something similar and use it as a template.
Tool handler pattern
Every tool must return McpToolResponse:
import type { McpToolResponse } from "../types/tools.js";
export async function handleMyTool(args: MyToolArgs): Promise<McpToolResponse> {
try {
const dirPath = validateDirPath(validateStringParam(args.dirPath, "dirPath"));
// ... do work ...
return { content: [{ type: "text", text: JSON.stringify(result, null, 2) })];
} catch (error: any) {
return { content: [{ type: "text", text: error.message }], isError: true };
}
}
BaseTool (for heavier tools)
Extend BaseTool<T> from tools/base.ts when you need built-in concurrency control, logging, and credential masking. Then wrap in a thin function for the registry:
class MyTool extends BaseTool<MyToolArgs> {
protected async run(args: MyToolArgs): Promise<McpToolResponse> {
// ... implementation ...
}
}
export async function handleMyTool(args: MyToolArgs): Promise<McpToolResponse> {
return new MyTool().execute(args);
}
Registration
Add the handler to ToolRegistry in tools/registry.ts. For class-based tools, pass as an override in index.ts.
Tool definitions
Add a JSON Schema entry to src/config/tools.json with name, description, and inputSchema.
Mandatory conventions
- ESM
.jsextensions: every local import MUST end in.js. - No implicit
any: use typed args fromtypes/tools.ts. - Input validation: always call
validateDirPathandvalidateStringParamat entry. - File scanning: use
FileScanner.findFiles()fromtools/base.ts— it handles.gitignore,includePath,excludePath. - App metadata: use
AppInfofromutils/app-info.ts, never hardcode version/name. - Concurrency: if doing IO, acquire/release
operationLimiterfromutils/semaphore.js. - Sensitive data: add new secret fields to
maskSensitiveintools/base.ts.
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.
- 2mo ago First seen · 61 lines · 21 tokens per session scan A 85ece7bd799c
code-writing is a skill published in the GitHub repository reasvyn/docsgrep (0 stars, last pushed 3mo ago), licensed MIT. It adds 21 tokens to every session and 542 once invoked, about $0.0001 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 2026-08-31.
Other skills, from other repositories
local-ai-agents
Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…
systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.
next-cache-components-adoption
Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…
chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…
insight-error-page
Write or audit an insight-kind error page for the Next.js dev overlay. Use when creating a new errors/ .mdx page, auditing an existing one, or checking that a page matches the framework fix cards. Covers page structure, title alignment, FixCard cards with Copy prompt button, code snippets, terminology verification…