What is spendlog CLAUDE.md?

A CLAUDE.md instruction file for Spendlog, an expense-tracking MCP server for Claude. It documents the technology stack, commands, architecture, database, and data flow.

Running development and production commands, testing and type-checking the project, managing database migrations and seed data, and understanding its SQLite expense database.

It tells the coding agent how this finance application stores data and how to develop, test, and migrate it safely.

How makz81/spendlog configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to makz81/spendlog. 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/makz81/spendlog/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/makz81/spendlog

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/makz81/spendlog/claude-md/github.svg)](https://agentmods.dev/instructions/makz81/spendlog/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/makz81/spendlog/claude-md"><img src="https://agentmods.dev/badge/instructions/makz81/spendlog/claude-md/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/makz81/spendlog/claude-md"><img src="https://agentmods.dev/badge/instructions/makz81/spendlog/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 663 This file is loaded in full into every session.

When invoked 663 The same file — it is already loaded in full.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00663	$0.00663
Opus 5.5	$0.00265	$0.00265
Sonnet 5.5	$0.00133	$0.00133
Haiku 4.5	$0.00066	$0.00066

Measured 2mo ago against content hash c921ae042d17, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

spendlog CLAUDE.md 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.md · 80 lines

How it starts

The opening of the file, as written. The whole thing — 80 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Spendlog

MCP server for expense tracking. Track finances directly in Claude.

Tech Stack

Layer	Technology
Runtime	Node.js 20+ (ESM, TypeScript strict)
MCP	@modelcontextprotocol/sdk
Database	TypeORM + better-sqlite3 (SQLite)
Validation	Zod
Testing	Vitest (382 tests)
i18n	EN (default), DE

Commands

npm run dev          # MCP server with watch mode (tsx)
npm run build        # TypeScript build
npm run start        # Run built server
npm run test         # Run tests
npm run typecheck    # Type check (no emit)
npm run db:migrate   # Run database migrations
npm run db:seed      # Seed default categories
npm run db:reset     # Reset DB (delete + migrate + seed)

Architecture

User -> Claude LLM -> MCP Tool Call -> Zod Validation -> Service -> TypeORM -> SQLite

Data Flow

MCP tools receive params via stdio (Claude Desktop) or HTTP/SSE (cloud)
Zod validates all inputs
Services contain business logic
TypeORM entities map to SQLite tables in ~/.spendlog/spendlog.db

Key Directories

src/
  index.ts              # MCP server entry point
  server.ts             # Server setup & tool registration
  cli.ts                # CLI installer (npx spendlog)
  constants.ts          # App constants
  tools/                # MCP tool definitions (one file per tool group)
  entities/             # TypeORM entities (Transaction, Invoice, etc.)
  services/             # Business logic (pdf, sync, connection)
  db/                   # Database setup, migrations, seeds
  i18n/                 # Translation dictionaries
templates/
  invoice.hbs           # Handlebars template for PDF invoices
tests/
  tools/                # Integration tests per tool group
  helpers/              # Test utilities
  fixtures/             # Test data factories

Code Conventions

TypeScript strict -- no any without comment
MCP Tools: snake_case names, Zod schemas, English descriptions (localized via i18n)
Services: camelCase functions, throw errors (handled in tool layer)
Entities: PascalCase, TypeORM decorators, UUID primary keys
Files: kebab-case (transaction-service.ts)
Imports: external -> internal -> relative, no circular deps
ESM: import/export, not require

Read the full file on GitHub · 80 lines

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.

2mo ago First seen · 80 lines · 663 tokens per session scan A c921ae042d17

Subscribe to this mod's changes

spendlog CLAUDE.md is an instructions file published in the GitHub repository makz81/spendlog (1 stars, last pushed 5mo ago), licensed MIT. It adds 663 tokens to every session, about $0.0027 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.

claude expense-tracker mcp mcp-server sqlite

spendlog CLAUDE.md next to 6 instructions from other repositories
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spendlog: Instructions file for Claude Code