The tool router for coding agents.

Give your agent superpowers once. Tenjin hands it the right tool when it helps, and you keep working like before.
No API keys. No pile of MCP servers. No rules to write.

Quick start · Tools · Wallet & payments · Request a tool

Why

Giving your agent good tools is a chore today:

• A key for every tool. Sign up, pick a plan, paste an API key into a config file. Five tools, five accounts.
• MCP servers crowd the context. Every server you install loads its tool definitions into every session, needed or not.
• Your agent forgets anyway. It reaches for plain web search out of habit, so you write rules to remind it, and it still slips.
• Some tools you need once. Installing something permanent for a one-off lookup isn't worth the setup.

Tenjin handles all of it. Install it once and keep working. The Tenjin router watches the moments where a tool could help: your prompt, your agent's web searches and page fetches, and the tasks it hands to subagents. When a curated tool beats what your agent was about to do, the router suggests it and your agent calls it. Your wallet pays for each call through x402, so you manage no keys and install nothing new.

Quick start

Requires Node.js 24 or newer and Claude Code. Codex support is on the way.

npm i -g tenjin-cli
tenjin install          # sets up Claude Code and creates your wallet
tenjin wallet fund 2    # optional: add $2 with a card, via Coinbase

✓ Tenjin is set up for Claude Code
✓ Wallet created: 0x3c0D84055994c3062819Ce8730869D0aDeA4c3Bf
  Automatic router: up to $0.25 per call; daily limit $5 a day

Next: tenjin wallet fund, then restart Claude Code

Restart Claude Code. That's it.

Then work as usual. Try:

> What are BTC and ETH trading at?
> How do I paginate list results with the Stripe Node SDK?
> Is ada@example.com a deliverable address?
> Integrate x^2 sin(x) dx from 0 to pi.

Each answer names the provider and the price. Your agent keeps its own tools, and the router steps in only when it has something better.

What it can do

The router picks from a catalog we curate and maintain. Routing is free: you pay the provider's price and nothing else.

Free tools run without a funded wallet. Twitter, Reddit and more are next, added by demand: tell us what you want.

How it works

flowchart LR
    A["Your prompt,<br>a web search,<br>or a subagent task"] --> B{"Tenjin<br>router"}
    B -- "a tool fits" --> C["Agent calls it<br>through x402"]
    C --> D["Wallet pays the provider,<br>result comes back"]
    B -- "nothing better" --> E["Agent carries on"]

The Tenjin router hooks into Claude Code at your prompt, before each web search or page fetch, and when your agent hands work to a subagent. At each point it asks Jev, a decision model from TypeSafe, whether a tool in the catalog fits. Jev can only choose from that fixed list, so it never writes a call or an instruction for your agent.

When one fits, your agent sees a one-line suggestion with the tool and its price, and calls it through Tenjin's x402 MCP server. Tenjin pays the provider from your wallet, within your limits, and hands back the result. Your status line shows the call as it happens:

x402 · request: calling pro-api.coinmarketcap.com/x402/v3/cryptocurrency/quotes/latest · {"query":{"symbol":"BTC,ETH"}}

To pick a tool, the router sends your current turn and up to six recent messages, with keys, passwords and seed phrases masked. Tool results and page contents stay on your machine, and the packet expires after 15 minutes. tenjin config set router.context turn sends only the current message. Full details, and everything install writes →

Wallet and payments

Tenjin pays for tools with x402, an open standard that builds payments into HTTP. A paid endpoint answers 402 Payment Required with its price, the client signs a payment for that amount, and the endpoint returns the result. Neither side needs an account or an API key. Read more: x402.org · whitepaper · Coinbase docs · spec and SDKs.

Your wallet

tenjin install creates a wallet on your machine that holds USDC on Base. Tenjin encrypts the private key, unlocks it through your OS keychain, and never sends it anywhere. Tenjin never holds or moves your funds. Paying a provider costs no gas.

Limits

Tenjin refuses any payment over either limit before it signs anything.

Funding

tenjin wallet fund 2 opens a Coinbase Onramp checkout for your wallet: pay by card, or Apple Pay where your region supports it. Sign in to Coinbase or create an account during checkout. You can also send USDC on Base to the address tenjin wallet show prints.

$1–2 goes a long way. $2 covers about 280 web searches, 200 page reads or 100 Wolfram Alpha answers.

Withdrawing

tenjin wallet send <amount> USDC <address> sends funds to any address. It's a regular onchain transfer, so it needs a little ETH on Base for gas.

Everyday commands

tenjin status                  # what you've spent today
tenjin wallet balance          # what's left
tenjin wallet fund 5           # top up
tenjin update                  # newest version; wallet and settings stay
tenjin config set router.enabled false             # pause the router on this machine
tenjin config set --project router.enabled false   # ...or just in this repo
tenjin uninstall               # remove the Claude Code setup; your wallet stays

Use tenjin install --project to set it up for a single project. Add --json to any command for machine-readable output.

(cd ~ && claude mcp remove x402 -s project)

Request a tool

Tenjin is in alpha, and the catalog grows with what people ask for. Missing a service your agent keeps needing? Hit a lookup that went to the wrong place? We want to hear it.

• Request a tool →
• Report a bug →

Learn more

• How a lookup runs, what it sends, and what install writes
• Safety model

Developing

Before contributing, read CONTRIBUTING.md for the contributor agreement.

pnpm install
pnpm run githooks   # once, to use the repo's git hooks
pnpm run build
pnpm run test
pnpm run typecheck
pnpm run lint