For developers and agents
FrankKi for developers
Green sandbox send in 10 minutes
Get a test token, complete your sender profile and send your first sandbox letter. No AVV, no wallet balance, no real letter goes out. The fastest way in is the Claude Desktop Quickstart.
Open the Claude Desktop QuickstartWhat FrankKi MCP is
FrankKi MCP is a hosted Model Context Protocol server that lets an AI agent draft, price, send and track letters, through a One-Shot-Send call instead of a multi-step form. Payment runs through a closed-loop wallet: you top up your balance once, every send debits it to the cent, with no per-letter card prompt.
Before you start
- Step 0
Account and onboarding step 1
Sign up yourself in the partner dashboard and complete the first onboarding step. No human approval, no AVV, no wallet top-up needed, about 1 to 2 minutes.
- Step 1
Get a test token
Right after onboarding step 1, a test token is ready in the dashboard. It costs nothing and sends no real letter.
- Step 2
Complete your sender profile
The sandbox runs all six real send gates, including the mandatory-fields check. A raw first call otherwise returns SENDER_PFLICHTANGABEN_INCOMPLETE with a link to fix it.
- Step 3
Green sandbox send
Check mcp_health, then call order_send with the sample data. No placeholder to guess.
Quickstart per client
Claude Desktop
Connect by pasting the test token, mcp_health and order_send in a few minutes.
Claude Code
MCP server configuration for the CLI, same Steps 0 through 3.
ChatGPT
Connect by pasting the test token. OAuth there currently runs live only.
Cursor
Set up the MCP server in Cursor and run your first sandbox send.
More reference
Tool reference
Every tool with name, description and fields, generated straight from the real registry.
Error catalog
Every error code with its meaning, recovery class and fix link.
Conventions
ISO-8601, cent amounts, idempotency and dryRun, in one place.
Letter design
Reusable letterhead, info block, footer, QR code and fold marks: save, preview and apply per letter with designId and reference.
Transcript: Tax advisor
A complete sandbox run to reproduce: create a preset, search a recipient, send, track status, fetch the proof of posting.
Transcript: SaaS batch
A complete sandbox run to reproduce: batch send with dryRun, a real send and replay proof.
Webhooks (preview)
Planned event types and signature contract, not live yet.
Changelog
API version state and upcoming changes.
Trust and live status
Machine-readable service facts and the current operational status of the partner interface are publicly available at all times, no login needed.