Make your agent check before it acts
Five SKILL.md files for Claude Code, Codex CLI, Cursor and any agent that reads skills. Each one is a procedure: when it applies, the one Factline call to make, and what to do with each verdict. Installed once, the agent runs the check every time the situation comes up.
The skills
| Skill | The agent runs it | Call |
|---|---|---|
| Verify before paying | Before it pays or approves a supplier invoice, or when bank details change | /v1/invoice/check: pass, review or hold |
| Check a counterparty | When a new customer, supplier or partner is onboarded | /v1/kyb/check and /v1/kyc/check: registers, sanctions, PEP |
| Check a Chinese supplier | Before it pays or onboards a supplier in China, or when an 18-character USCC appears | /v1/china/supplier-check: USCC, sanctions, Entity List, UFLPA |
| Before an x402 payment | When it gets an HTTP 402 challenge and is about to pay | /v1/pay/guard: allow, review or deny (free) |
| Dutch address and vehicle facts | When a Dutch address, postcode or licence plate comes up | /v1/home/basic, /v1/vehicle/basic and more (free) |
Install
Claude Code, skills plus the Factline MCP server:
/plugin marketplace add factline-dev/factline-skills
/plugin install factline@factlineAny agent that reads SKILL.md:
npx skills add factline-dev/factline-skillsOr copy the folders from github.com/factline-dev/factline-skills into your agent's skills directory. MCP clients can also read them as resources (skill://factline/<name>) on every Factline server. Index: /skills.json.
Keys
The pay guard and the Dutch basics are free. Paid checks: 5 free a day, then a free trial key (2,000 credits a month) or x402 per call. The skills send X-Factline-Client: skill-<name> (the skill name only, never the query) so we can see which ones help.