mcify: Command for Claude Code

.claude/commands/add-tool.md

add-tool is a command for Claude Code from Lelemon-studio/mcify. It costs 15 tokens per session (584 once invoked), scanned A, original, Apache-2.0.

A command that creates the initial TypeScript file for a new MCP tool, including input and output schemas and a placeholder handler. MCP is a standard way for an AI application to call external tools.

In plain words
What is it for?
Use it when adding a tool to an example connector or to your own project. Provide a valid tool name, then fill in its schemas and handler.
Why use it?
It gives a new tool the expected project structure and validation setup, so you do not have to create the boilerplate by hand.

Command for Claude Code

Written for Claude Code: installed under .claude/.

This is Lelemon-studio/mcify's own configuration. It tells Claude Code how to work on mcify itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything mcify configures →

Reuse

Borrowing it

Nothing to install: this file belongs to Lelemon-studio/mcify. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/Lelemon-studio/mcify/main/.claude/commands/add-tool.md
Clone the repo
git clone --depth 1 https://github.com/Lelemon-studio/mcify

Made for: Claude Code.

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 add-tool

README.md
[![agentmods](https://agentmods.dev/badge/commands/lelemon-studio/mcify/add-tool/github.svg)](https://agentmods.dev/commands/lelemon-studio/mcify/add-tool)
Your own site
<a href="https://agentmods.dev/commands/lelemon-studio/mcify/add-tool"><img src="https://agentmods.dev/badge/commands/lelemon-studio/mcify/add-tool/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 add-tool

Your own site · 80×15
<a href="https://agentmods.dev/commands/lelemon-studio/mcify/add-tool"><img src="https://agentmods.dev/badge/commands/lelemon-studio/mcify/add-tool.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 15 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 584 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 $0.00015 $0.00584
Opus 5.5 $0.00006 $0.00234
Sonnet 5.5 $0.00003 $0.00117
Haiku 4.5 $0.00002 $0.00058

Measured 2mo ago against content hash 6829de0a0954, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

add-tool 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.

.claude/commands/add-tool.md · 68 lines

What it actually says

Scaffold a new MCP tool — either in an example connector or in the user's own project.

Required input from the user: the tool name (e.g., khipu_create_payment).

  1. Validate the name against /^[a-zA-Z0-9_-]{1,64}$/. Reject if it doesn't match (this is the same regex defineTool enforces at runtime).

  2. Find the right home for the tool. Ask the user only if it's not obvious:

    • In a packages/examples/<connector>/ example: add to that connector's tools/ directory.
    • In a user project: add to tools/ next to mcify.config.ts.
  3. Write the tool file as <name>.ts:

    import { defineTool, schema } from '@mcify/core';
    import { z } from 'zod';
    
    export const <camelName> = defineTool({
      name: '<name>',
      description: '<one sentence, present tense>',
      input: z.object({
        // schema.id(), schema.url(), schema.money(), etc. for common shapes
      }),
      output: z.object({
        // ...
      }),
      handler: async (input, ctx) => {
        throw new Error('not implemented');
      },
    });
    

    Suggest sensible Zod helpers from @mcify/core's schema namespace where applicable (schema.id, schema.url, schema.httpUrl, schema.money, schema.timestamp, schema.paginated).

  4. Register it in mcify.config.ts:

    import { <camelName> } from './tools/<name>.js';
    
    export default defineConfig({
      // ...
      tools: [<camelName>, /* ... existing ... */],
    });
    
  5. Add a basic test as tools/<name>.test.ts:

    import { describe, it, expect } from 'vitest';
    import { <camelName> } from './<name>.js';
    
    describe('<name>', () => {
      it('rejects invalid input', () => {
        const result = <camelName>.input.safeParse({});
        expect(result.success).toBe(false);
      });
    
      // Add a happy-path test once the handler is implemented.
    });
    
  6. Verify: run pnpm typecheck and pnpm test for the affected package. Don't write the actual handler logic — the developer fills that in.

  7. Don't add a changeset unless the tool ships in a published example. User-project tools never get changesets.

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. 2mo ago First seen · 68 lines · 15 tokens per session scan A 6829de0a0954

Subscribe to this mod's changes

add-tool is a command published in the GitHub repository Lelemon-studio/mcify (2 stars, last pushed 4mo ago), licensed Apache-2.0. It adds 15 tokens to every session and 584 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.

Related

add-tool compared with commands from other repositories

add-tool next to 6 commands from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
add-toolLelemon-studio/mcifyCommand24mo agoApache-2.0A15Claude Code
initfcakyon/claude-codex-settingsCommand1.2kyesterdayApache-2.0A0Claude Code
http-serviceMadAppGang/magusCommand14yesterdayMITA27Claude Code
buildAzure/ai-gatewayCommand510d agoMITA0Claude Code
api-contract-reviewMozurok/fhorja.devCommand1028d agoMITA64Claude Code
start-10-1minicoohei/ai-agent-campCommand3471mo agononeA2Claude Code
fastapimfmezger/ai_agent_dotfilesCommand73mo agoMITA84Claude Code, Gemini CLI