mimirapi

Official isomorphic TypeScript/JavaScript client for MimirAPI — pay-per-call tools for agents over x402 (USDC on Base).

No API key. No signup. Discovery is free; paid routes quote a price with HTTP 402, you settle it, and retry. Zero dependencies — runs on Node 18+, Bun, browsers, and Cloudflare Workers.

npm install mimirapi

Browse the shelf (free)

import { MimirApiClient } from 'mimirapi';

const mimir = new MimirApiClient();

const { skus } = await mimir.catalog();
for (const sku of skus) {
  console.log(`${sku.id} — $${sku.priceUsd}/call — ${sku.method} ${sku.path}`);
}

catalog(), sku(id), and health() are never metered.

Call a paid tool

Without a settler, a paid route throws PaymentRequiredError carrying the quote:

import { PaymentRequiredError } from 'mimirapi';

try {
  await mimir.call('/v1/ping');
} catch (err) {
  if (err instanceof PaymentRequiredError) {
    console.log(err.accepts); // [{ scheme: 'exact', network: 'base', maxAmountRequired: '1000' }]
    // Settle one of these, then retry the same request.
  }
}

Bring your own wallet

This package ships no wallet. Bundling signing keys into a client library is how people lose money — you plug in a settler and the client handles everything around it: the 402 round trip, the price ceiling, and the retry.

const mimir = new MimirApiClient({
  maxPriceUsd: 0.05,
  settle: async (challenge, { url }) => {
    // Sign an EIP-3009 authorization for challenge.accepts[0] and return the
    // PAYMENT-SIGNATURE header value. Return null to decline.
    return signWithYourWallet(challenge, url);
  },
});

const pong = await mimir.call('/v1/ping'); // pays $0.001 and returns the result

The safety rails

• maxPriceUsd (default 0.25) is checked before the settler is invoked. A counter that raises its price — or a bug — cannot drain a wallet; you get PriceCeilingError instead.
• An unparseable or absent quote is treated as Infinity, never as free.
• A second 402 is never retried. If settlement did not take, retrying risks paying twice, so the client throws instead.

Input shapes

method follows the catalog row: GET SKUs take query params, POST SKUs take a JSON body.

await mimir.call('/v1/qr', { method: 'GET', input: { data: 'hello' } });
await mimir.call('/v1/db', { input: { ttlSeconds: 300 } }); // POST inferred from input

Errors

| Class | When | |---|---| | PaymentRequiredError | 402 with no settler, a declined settle, or a second 402 | | PriceCeilingError | quote exceeded maxPriceUsd; the settler was never called | | MimirApiError | any other non-2xx, plus network failures (status: 0, code: 'network_error') |

Discovery surfaces

MimirAPI is agent-native. Beyond this client:

• Catalog — https://mimirapi.com/v1/catalog
• Agent overview — https://mimirapi.com/llms.txt
• MCP server — POST https://mimirapi.com/mcp
• OpenAPI 3.1 — https://mimirapi.com/.well-known/openapi.json

License

MIT