The tool router for coding agents.
Install · Try it · Tools · Wallet and limits · Request a tool
Why
Giving your coding agent good tools is a chore:
- A key for every tool. Sign up, pick a plan, paste an API key. Five tools, five accounts.
- MCP servers crowd the context. Each one loads its tool list into every session, needed or not.
- Your agent forgets anyway. It reaches for plain web search, so you write rules, and it still slips.
- Some tools you need once. A one-off lookup isn't worth the setup.
With Tenjin, you install once and keep working. The router suggests the right tool when it helps, and your wallet pays per call. No keys, no extra servers, no rules.
Install
Paste this into Claude Code:
Install Tenjin from tenjin.sh
Your install request gives the agent permission to handle setup. It briefly explains task-context sharing, asks about spending limits and adding funds, then gives the activation step. Follow that step to continue your original task. Wallet addresses appear only when requested or needed for recovery; storage and PATH details appear only for recovery.
Or from a terminal (Node and npm are not required):
(
tenjin_install_dir="$(mktemp -d ./.tenjin-install.XXXXXXXX)" || exit
trap 'rm -f "$tenjin_install_dir/install.sh"; rmdir "$tenjin_install_dir"' EXIT
curl -fsSL https://tenjin.sh/install.sh -o "$tenjin_install_dir/install.sh" &&
sh "$tenjin_install_dir/install.sh"
)
On Windows, in PowerShell:
irm https://tenjin.sh/install.ps1 | iex
The installer downloads a pinned Node and Tenjin, verifies both, and sets up
the plugin. Supports macOS 13.5+, Windows and glibc Linux 2.28+ on x64/arm64.
Musl/Alpine and other platforms are unsupported. Needs Claude Code 2.1.287+.
Tenjin runs from ~/.tenjin/runtime; changing or removing your system's Node
later does not stop it. Add --project to tenjin install for one project.
Plugin installation uses the default data directory; run without
TENJIN_DATA_DIR. Other CLI commands can still use a custom data directory.
Already use npm? Run npm i -g tenjin-cli, then tenjin install. It sets up
the same private runtime. An installation failure keeps your existing plugin
registration. Check the reported cause, then retry the install.
Agent-run installs return a compact handoff. tenjin install --json installs
with the full structured result for scripts or troubleshooting.
Codex (experimental): run tenjin install in Codex or a terminal, and it sets up Codex too. How it hooks in →
Try it
Work as usual. Ask for something your agent can't do on its own:
> Generate a 10-second voiceover that says "Welcome to Tenjin"
> Make a whoosh sound effect for a page transition
> Make a hero image of plum blossoms in ukiyo-e style
> Make a 5-second video of a paper crane unfolding
> Summarize the risk factors in Nvidia's latest 10-K
> What are people on Reddit saying about Bun vs Node lately?
The router names the tool and its price, and your agent calls it.
What your agent can do
| Your agent needs | With | Provider price |
|---|---|---|
| Library docs | Context7 | free |
| Web search and page reads | Exa, Firecrawl | 0.1¢ to 1.5¢ |
| Math and live crypto prices | Wolfram Alpha, CoinMarketCap | 1¢ to 2¢ |
| People, companies and emails | Apollo, Hunter, CompanyEnrich | 0.8¢ to 15¢ |
| X and Reddit | glim | 0.1¢ to 1¢ |
| Images | GPT Image, Nano Banana, Recraft | 0.1¢ to 14.4¢ |
| Voiceovers, sound effects, music | ElevenLabs, Google Lyria | 1¢ to 12¢ |
| Video clips | MiniMax Hailuo, Google Veo | 15.5¢ to 45¢ |
| Papers and SEC filings | arXiv, PubMed, SEC EDGAR | 0.3¢ to 4¢ |
| Instagram, TikTok and Google Maps | Scrape Creators, Google Maps | 2¢ |
| PDFs, OCR, screenshots, hosting, email | Cloudflare and others | 0.2¢ to 50¢ |
Provider prices above exclude Tenjin's $0.003 fee per paid routing call. We review every tool by hand. Every tool and its current price →
How it works
- The router watches the moments a tool could help: your prompt, each web search or page fetch, each task handed to a subagent, and each question your agent asks you.
- Jev, a decision model from TypeSafe, picks one tool from the catalog, or none. Your agent sees one line naming the tool and its price.
- Your agent calls it through the plugin's
requesttool, and your wallet pays the provider. When nothing fits, your agent carries on with its own tools.
The router sees your prompt and up to six earlier messages, with secrets masked, and never sees tool results. What the hooks send →
Wallet and limits
tenjin install creates a wallet on your machine that holds USDC on Base. Its key never leaves your machine, and Tenjin never holds your funds. Payments run over x402 (whitepaper, Coinbase docs).
| Limit | Default | Change it |
|---|---|---|
| Per 24-hour window | $5 | tenjin config set sessionBudget 2 |
| Per call | $0.25 | tenjin config set maxAutoSpend 0.50 |
The automatic budget window is shared across agent sessions. When the window ends, its counted automatic spend resets.
- A call over a limit pays nothing until you say yes. The per-call limit can't go below $0.25.
- Each paid routing call costs $0.003, even when no tool is suggested, separate from provider charges. Tenjin sets aside $0.25 at a time for these fees, or $0.03 while your balance is under $0.50 so the rest stays available for paid tools, and stops routing below $0.03; unused funds remain yours, and deposits count toward your spending limits once. Browsing tools and their specs is free.
- Add funds with
tenjin wallet fund 5, or send USDC on Base to the addresstenjin wallet addressprints.
How the limits and the fee work →
Commands
tenjin status # your balance, spending and limits
tenjin wallet balance # what's left
tenjin payments # paid lookups from this machine
tenjin doctor # check that a lookup can run
tenjin update # newest version now (it also updates itself daily; `tenjin config set update.mode off` stops that)
tenjin config set router.enabled false # pause the router
tenjin uninstall # your wallet stays; npm installs: then `npm uninstall -g tenjin-cli`
Request a tool
Tenjin is in alpha, and the catalog grows with what people ask for.
