TonnrOpen the map

Plug your assistant into the sea. An MCP server and an API, read-only: buoys, wind, forecasts, tides and breaks, each with its source.

With your account

In Claude or ChatGPT, with no key: the assistant asks you to sign in to Tonnr, then reads the sea and what your account keeps. It changes nothing.

The address to paste

https://api.tonnr.app/mcp

  • Claude

    Add a custom connector with this address, then sign in with your Tonnr account. Works without a subscription.

    Open Claude

  • ChatGPT

    Turn on developer mode, create an app with this address, then sign in with your Tonnr account. Needs a paid plan.

    Open ChatGPT

What it can read

Every tool reads, none writes. Every answer says where its data comes from, and under which licence.

The sea and the breaks

  • list_stationsBuoys and wind stations in an area, with their latest reading
  • get_stationOne station and its latest reading
  • get_station_readingsWhat a station measured over a period
  • get_forecastThe hourly forecast of waves, wind and weather, up to 7 days
  • get_tide_extremesHigh and low tides near a point
  • get_tide_timelineThe tide's height, step by step
  • list_surf_breaksThe breaks in an area, with what is known of each
  • search_surf_breaksA break by its name or its town's
  • get_surf_breakOne break of the catalogue
  • get_surf_break_guideThe guide written by those who surf it: access, entry, hazards, rules

Your account, once signed in

  • list_my_spotsYour spots
  • list_my_alertsYour alerts, and the conditions each one waits for
  • list_my_alert_notificationsWhat your alerts told you
  • list_my_sessionsYour log of sessions
  • get_my_sessionOne session, with the conditions of that day
  • get_my_sessions_recapWhat your log comes to: totals and the places surfed most

For developers

An API and an MCP server, read-only, with a key. For now I hand the keys out myself: tell me what you're building.

Connect by MCP

claude mcp add --transport http tonnr https://api.tonnr.app/mcp \
  --header "Authorization: Bearer $TONNR_KEY"

Read-only tools over Streamable HTTP, with one key and the limits of the API.

Prompt

Read https://tonnr.app/llms.txt, then use the Tonnr API to tell me what the sea does at my spot over the next three days: swell, wind and tide.

Request

curl https://api.tonnr.app/v1/stations/candhis-05602 \
  -H "Authorization: Bearer $TONNR_KEY"

{
  "id": "candhis-05602",
  "name": "Belle-Ile",
  "latestReading": {
    "significantHeightMeters": 1.9,
    "peakPeriodSeconds": 9,
    …
  },
  "attribution": "…",
  "license": { … }
}