Luca Assistant (撸卡助手)

A credit card rewards optimization tool. Query 150+ US credit cards, compare benefits, track your portfolio, and find the best sign-up bonuses.

When to use this skill

Trigger this skill when the user asks about:

• - Credit card recommendations or comparisons
• Sign-up bonuses (SUBs) or welcome offers
• Chase 5/24 status or bank application rules
• Adding/removing cards in their portfolio
• Card benefits, category multipliers, or annual credits

Setup

Check if already installed

Before running setup, check whether Luca is already available:

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If luca-mcp responds, skip to How to use. Otherwise run setup below.

First-run setup

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This installs luca-assistant from PyPI via uv and seeds the database (~150 cards from Offer Optimist).

PATH note: uv tool install places binaries in ~/.local/bin. If luca-mcp is not found after setup, ensure ~/.local/bin is on PATH (export PATH="$HOME/.local/bin:$PATH").

Verify setup

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How to use

Luca is an MCP tool server. The database lives at ~/.local/share/luca/luca.db.

If Luca is already configured as an MCP server in the agent's environment, call luca_* tools directly. Otherwise, call tools via the bundled script:

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Available MCP tools

Card queries:

• - luca_query_card_details(card_name, bank?) — look up a card's benefits, current offers, and fees
• INLINECODE11 — best current sign-up bonuses
• INLINECODE12 — side-by-side benefit comparison
• INLINECODE13 — issuer application rules (Chase 5/24, Amex lifetime language, Citi 8/65, etc.)

Card enrichment:

• - luca_update_card_benefit(card_name, category, multiplier, points_type, notes?, bank?, annual_credit?, credit_category?) — add or update a card's category multiplier or credit
• INLINECODE15 — refresh data from 'offer-optimist' (cards + SUBs) or 'cfpb' (APRs + fees)

Portfolio tracking:

• - luca_get_user_portfolio() — user's open and closed cards
• INLINECODE17 — 5/24 count and remaining slots
• INLINECODE18 — add a card to portfolio
• INLINECODE19 — mark a card as closed

Examples

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Enrichment workflow

When luca_query_card_details returns a multiplier_hint, the card has missing category multiplier data. To fill the gap:

1. 1. Web search for the card on INLINECODE22
2. Find the earning rates (e.g., "3x on dining, 2x on travel")
3. Call luca_update_card_benefit for each category to persist the data

Optional: USCardForum integration

For community data points from USCardForum (美卡论坛), install the companion nitan skill. It provides discourse_search, discourse_read_topic, discourse_list_hot_topics, and more.

Guidelines

• - All card data comes from the database — never fabricate card details
• If a card isn't found, tell the user rather than guessing
• Respond in the user's language (Chinese or English)
• Use luca_import_cards to refresh data if it seems stale