Skill

mercury

Business banking API for accounts, transactions, payments, recipients, cards, invoices, treasury, and webhooks

Verified: 2026-05-13 (printing-press-ingest-2026-05-13+enrich-capability-skill)

When to use mercury

Choose if

You're running a finance/treasury agent that needs to read or move money through Mercury — account balances, ACH/wire transfers, invoice lifecycle, card issuance, treasury management, webhook subscriptions — with a built-in dry-run + idempotency-key approval plan that prevents accidental duplicate payments. Alternative class is Mercury's REST API direct, or Plaid + a separate payment rail; pick this CLI when you want the typed approval-plan pattern + offline SQLite sync.

Avoid if

You need multi-bank coverage (Brex, Ramp, Wise, traditional banks) — Mercury-only by scope. Also avoid for personal banking (Mercury is business-only). Production money-movement workflows need human-in-the-loop approval gates on top of the CLI's safety belt.

Risk Flags

  • HIGH auth Bearer-token credential controls real money movement. The README's safety pattern is a read-only approval plan (body + idempotency key + dry-run command + execute command) issued before any payment or transfer writes, plus explicit --yes for destructive actions.
  • HIGH data_quality "This action cannot be undone" applies to invoice cancellations and customer deletions. Agents must dry-run mutations and confirm idempotency keys before live execution.
  • MEDIUM runtime Webhooks can be auto-disabled after consecutive delivery failures — long-running listeners need health-check polling to detect silent deactivation.

Cost

Type: Freemium · Free tier: The CLI binary is free to install. Mercury's business banking is free at the account level for standard ACH; the agent uses a MERCURY_API_TOKEN bearer credential.

Hidden costs

  • The CLI is a free wrapper; Mercury's bank account pricing (per-wire fees, international transfer fees, treasury yield spreads) is the actual cost. No CLI subscription required.

Install

Default

npx -y @mvanhorn/printing-press install mercury
# Configure Mercury API bearer token:
export MERCURY_API_TOKEN=<your-token>
# Destructive actions require explicit --yes

Setup docs →

Estimated time to first success: ~10 min

Dependencies

Minimum runtime: Node.js 18+ (via npx) or Go 1.26.3+ for source install

Distribution

Repository
https://github.com/mvanhorn/printing-press-library
License
MIT