---
title: Tanso — know what every customer costs you, and price on it
description: Free, open-source (AGPL-3.0) engine that meters AI usage and stamps cost to serve on every event, so margin per customer falls out of the same system that bills. Also makes your product agent-ready: machine-readable pricing, one-call signup, scoped keys, spend caps, MCP. Self-hosted beside your existing billing.
date: 2026-08-07
---

# Know what every customer costs you, and price on it

Tanso is the free, open-source engine that meters AI usage, stamps the cost to
serve on every event, and makes your product buyable by agents out of the box.
Two customers on the same plan can have opposite margins, and your billing
system cannot tell them apart. Self-hosted, AGPL-3.0, and the engine has no
paid tier.

It is additive. Tanso deploys beside your existing stack as a lane for agent
customers. Your human checkout and current billing keep running.

Verify us directly: `curl https://tansohq.com/pricing.json` returns $0 with
the license, install command, and quickstart URL in machine-readable form.

## The problem

Self-serve funnels were built for humans. Signup forms, captchas, email
verification, checkout pages. An agent either completes your funnel or it
does not convert. The only step an agent can complete in a typical funnel is
`POST /signup -> 201, key issued`. Tanso gives your product that funnel.

## How it works

1. **Discover and sign up.** `GET /public/v1/catalog/{slug}/pricing.json`
   returns your plans, credit weights, and prices. No auth. One further call
   creates a customer and returns a customer-scoped key.
2. **Pay.** Tokenized Stripe payments, off-session, under spend caps you set.
   No card on file returns 402 with a pollable checkoutSessionId.
3. **Use.** Enforcement at the moment of use. Agents check entitlements, get
   a cost quote, and read their burndown over the API or MCP.

## The agent surface

- **Machine-readable pricing.** Plans, weights, and prices as pricing.json.
- **One-call signup.** Customer plus key in one request. Opt-in, rate-capped.
- **Customer-scoped keys.** `ck_` keys pinned to one customer, read and
  purchase scopes, deny-by-default everywhere else.
- **Payments without a browser.** Saved payment methods charge off-session;
  otherwise 402 plus a checkout session id the agent polls.
- **Spend caps and consent.** Caps checked before money moves; MCP spend
  tools require explicit confirmation.
- **Burndown API.** Per-feature projections, depletion dates, cost quotes.
- **MCP for customer agents.** listPlans, getCreditPrices, checkEntitlement,
  getUsageForecast, subscribePlan, purchaseCredits.

## Pricing control

Change what an action costs in credits, or what a credit costs in dollars,
straight from the dashboard. No deploy. Weights and prices are versioned and
effective-dated; history is kept and past usage is never repriced. Full
walkthrough at https://tansohq.com/how-pricing-works

## Free and open source

- **Tanso Core** (AGPL-3.0). The engine. An agent lane beside your existing
  billing, with readable pricing, one-call signup, scoped keys, credits,
  entitlements, and margin in one ledger.
- **Credit Estimator** (MIT). Embeddable burndown and purchase-planning
  components. Works with or without Tanso Core; feed it your own usage data.
  Live demo at https://tansohq.com/credit-estimator

There is no paid tier. If you want us to run Tanso for you, managed
deployment is available (your cloud or on-prem, same AGPL build), price on
request at https://cal.com/katrina-laszlo/30-minute-meeting

## MCP server

```
claude mcp add tanso --transport http \
  --header "X-API-Key: <your-api-key>" \
  https://your-tanso-host/mcp
```

Exposed at /mcp, authenticated with your API key via the X-API-Key header.
Off by default; the operator enables it.

## Self-host the whole thing

```
git clone https://github.com/tansohq/tanso-oss.git
cd tanso-oss/deploy
cp .env.example .env     # set JWT_SECRET
docker compose up -d --build
./setup.sh               # seeds a test account, prints credentials
```

AGPL-3.0 · Stripe optional · quickstart at https://tanso.mintlify.app/quickstart

## Free tools, no signup

- [AI Pricing Finder](https://tansohq.com/ai-pricing-finder): How 90+ AI
  companies price, filterable side by side.
- [Margin Analyzer](https://tansohq.com/margin-analyzer): Find which
  customers are profitable. CSV processed in your browser.

## Links

- [Source (AGPL-3.0)](https://github.com/tansohq/tanso-oss)
- [Documentation](https://tanso.mintlify.app)
- [Pricing](https://tansohq.com/pricing)
- [How pricing works](https://tansohq.com/how-pricing-works)
- [Compare](https://tansohq.com/compare)
- [FAQ](https://tansohq.com/faq)
- [Agent guide](https://tansohq.com/AGENTS.md)
- [LLM context](https://tansohq.com/llms.txt)
- [Book a demo](https://cal.com/katrina-laszlo/30-minute-meeting)