Fathom plugin

Use Fathom through Corsair: one client, typed API calls. Fathom Analytics provides simple, privacy-first website analytics without cookies or tracking personal data. To connect to the API, generate an API token from your Fathom dashboard under Settings -> API (or https://app.usefathom.com/api). Provide the API token as key or store it in your account keys under api_key. Things to know:

Rate limits: Fathom enforces both an hourly volume limit and a concurrency limit per account. When exceeded, the API returns HTTP 429 with a Retry-After header.
Retired endpoints: Fathom retired the Wipe endpoints and the event-by-ID endpoints (events.create, events.get, events.update, events.delete, events.wipe, sites.wipe); they return HTTP 410 Gone. Events now appear once your site tracks them: read them with events.list and set their currency with events.setCurrency. events.deleteByName only removes an event’s currency setting; it does not delete the event or its completions. Wiping data is no longer possible through the API.
Aggregation filtering: Use reports.aggregation to query pageview or event analytics with flexible grouping and date ranges. Filters are structured objects matching supported operators (is, is not, is like, is not like, matching, not matching).

What you get:

23 typed API operations

Setup

Install

npm install corsair @corsair-dev/fathom better-sqlite3
npm install --save-dev @types/better-sqlite3

yarn add corsair @corsair-dev/fathom better-sqlite3
yarn add --dev @types/better-sqlite3

pnpm install corsair @corsair-dev/fathom better-sqlite3
pnpm install --save-dev @types/better-sqlite3

bun add corsair @corsair-dev/fathom better-sqlite3
bun add --dev @types/better-sqlite3

Add the plugin

corsair.ts

import Database from 'better-sqlite3';
import { createCorsair } from 'corsair';
import { fathom } from '@corsair-dev/fathom';

export const corsair = createCorsair({
	plugins: [
		fathom(),
	],
	database: new Database('corsair.db'),
	kek: process.env.CORSAIR_KEK!,
	multiTenancy: true,
	hub: {
		projectApiKey: process.env.CORSAIR_API_KEY!,
		signingSecret: process.env.CORSAIR_SIGNING_SECRET!,
	},
});

With multiTenancy: true, scope calls with corsair.withTenant(id). See Quick start for KEK + Hub keys, and Multi-tenancy for account isolation.

Choose authentication

API Key (Recommended)

Store the Fathom API key before the first call: pnpm corsair setup --plugin=fathom --tenant=acme api_key=<your-key> (leave out --tenant without multiTenancy), or pass it as key in the plugin options. With Hub, each tenant enters their own key on the connect page. See API key auth.

fathom()

More: API Key

Connect a tenant

Mint a connect link and send the tenant to it. Hub hosts the page and delivers the result to your app — see Connect / OAuth.

const { connectUrl } = await corsair.manage.connect.createLink({
	plugin: 'fathom',
	tenantId: 'acme',
});
// redirect the user's browser to connectUrl

Example API calls

List sites in Fathom

const tenant = corsair.withTenant('acme');
await tenant.fathom.api.sites.list({ limit: 10 });

Create a new site in Fathom

const tenant = corsair.withTenant('acme');
await tenant.fathom.api.sites.create({ name: 'My Portfolio Website' });

See the full list on the API page.

What’s next

API reference

Every fathom.api.* operation with input and output types.

Connect / OAuth

createLink, Hub delivery, and tenant connect flows.

Use with agents

Expose this plugin’s operations as MCP tools.

Overview

Plugins