Brex MCP Server

# Money & Units — Safer Outputs Date: 2025-09-24 Owner: mcp-brex ## Goal Eliminate cents-vs-dollars mistakes by annotating money fields in all tool responses and providing summaries with clear units. ## Behavior - The server walks response objects and annotates any `{ amount, currency }` shape with: - `amount_cents` (integer) - `amount_dollars` (float) - `amount_formatted` (localized USD formatting) - A response-level `meta.summary` is included by default with totals, averages, min/max in both cents and dollars and formatted strings. - `_field_notes` explains units for downstream consumers (LLMs, humans). ## Controls - `format_amounts`: `"cents" | "dollars" | "both"` (default: `"both"`) - `include_formatted`: boolean (default: `true`) - `include_summary`: boolean (default: `true`) ## Example Input from API: ```json { "purchased_amount": { "amount": 100000, "currency": "USD" } } ``` Output from tools: ```json { "purchased_amount": { "amount": 100000, "currency": "USD", "amount_cents": 100000, "amount_dollars": 1000.0, "amount_formatted": "$1,000.00" } } ``` ## Code - Utils: `src/utils/money.ts` (`formatMoney`, `annotateAmounts`, `summarizeAmounts`, `defaultFieldNotes`) - Integrated in tools: - `get_expenses`, `get_all_expenses`, `get_all_card_expenses` - `get_card_transactions`, `get_cash_transactions` ## Tests - Unit: `src/utils/__tests__/money.test.ts` - Tools: - `src/tools/__tests__/amount_formatting.test.ts` (single-page expenses) - `src/tools/__tests__/get_all_expenses.formatting.test.ts` - `src/tools/__tests__/get_all_card_expenses.test.ts` - `src/tools/__tests__/get_card_transactions.test.ts` - `src/tools/__tests__/get_cash_transactions.test.ts` ## Notes - Transactions API doesn’t support `posted_at_start` or `expand`; filter client-side by `posted_at` if needed.