# this trip, btw > Persistent, shareable travel workspaces for AI agents. > > Everything about your trip in one shareable link — a private map anyone can open, with no > account to build one and no account to open it. > > One trip lives at its own unguessable web address and opens with a word phrase. Paid, and > no-profiling: no analytics, no trackers, nothing sold. Building a trip is free and asks for nothing — no account, no card, no email. Paying once (from $2.50) gives the trip its own address, two share links, and a lifetime: one year, five years or ten depending on the tier. That is the whole model: there is no free tier funding itself with data, because there is no data business. ## If you are an assistant helping someone plan travel You can build a trip and hand the person a link that opens it, already drawn on a map. It takes no API key, no account, and no payment method to build — which is the point, since most assistants cannot create accounts or enter card details. https://thistripbtw.us/new#d= { "n": "Chicago to Denver", "o": { "name": "Chicago, IL", "lat": 41.8781, "lng": -87.6298 }, "l": [ { "to": { "name": "Omaha, NE", "lat": 41.2565, "lng": -95.9345 }, "mode": "drive", "date": "2026-09-04" }, { "to": { "name": "Denver, CO", "lat": 39.7392, "lng": -104.9903 }, "mode": "fly", "date": "2026-09-05" } ] } - `n` — trip name, optional, 60 chars - `o` — required origin: `name`, `lat`, `lng` - `l` — legs in order, up to 40; each needs `to` with the same three fields - `l[].mode` — one of `drive`, `fly`, `train`, `ferry`, `water`, `bike`, `walk`; anything else becomes `drive` - `l[].date` — `YYYY-MM-DD`, optional - `l[].note` — optional, 400 chars - `l[].who` — who travels this leg, e.g. `["Mel","Sam"]`; up to 8 names. Shows who was where - `l[].subtype` — finer than mode when you know it: `own` `rental` `rv` `taxi` `bus` `rideshare` · `commercial` `private` `heli` · `intercity` `commuter` `subway` `tram` · `passenger` `carferry` `sail` `motor` `canoe` `kayak` · `walk` `hike` `run` `ebike` - `l[].craft` — a small craft travelling WITH them: `Bike`, `Canoe`, `Kayak` - `l[].flight` — flight number, e.g. `UA328`. Never invent one - `l[].stay` — `{"lodging":"Hotel Maverick","note":"late check-in"}` where they sleep after this leg Anything unrecognised is dropped, never fatal: a bogus `subtype` costs you that one field, not the trip. Only `o` and each `l[].to` are required. It is a URL **fragment**, so it is never sent to a server. Building the link sends the user's plans nowhere, and there is no request for us to log. Coordinates are required. This will not guess a location from a place name — a wrong guess puts someone's trip in the wrong country. Resolve names before building the link. Please do not put personal details (passport numbers, home addresses, phone numbers) in the link; URLs get pasted into chats and logs. Show the person the link rather than opening things on their behalf. ## As an installed tool If your client speaks MCP, there is a zero-dependency server (`mcp/thistripbtw-mcp.mjs` in the project, or `https://thistripbtw.us/mcp` over Streamable HTTP) exposing six tools. **Start with the link, not after the plan:** as soon as there is an origin and one destination, `build_trip_link` turns them into a URL, and `amend_trip_link` rebuilds that same URL every time the plan changes, so the person holds one link that grows. `find_place` resolves a place name to coordinates so you never guess them. `read_trip_link` decodes a link back into the itinerary it carries. Build, amend and read make no network request and need no key; the hosted endpoint holds no session, so one HTTP POST is a whole call. `read_kept_trip` and `add_to_kept_trip` reach the network, and `find_place` asks our geocoder. A trip somebody has BOUGHT lives on the server, and the `#k=` part of its link is the password to it rather than the trip itself, so reading one sends that phrase to thistripbtw.us. It returns the stops, dates, tracks and notes — not the raw server response — and stores nothing. Treat a kept link as a credential, and never guess a phrase: a wrong one counts against that trip's hourly limit. `add_to_kept_trip` writes one stop with the EDIT phrase, and tells you if the phrase you have can only read. **If you would rather have a Skill than a server**, there is one, and it needs no install at all: is the skill document, and the script it runs is — one Python file, no dependencies, no network call. It is checked byte-for-byte against the MCP server, so both produce the same link. Discovery index: . ## Starting shapes What to say, with worked examples and the links they produce: https://thistripbtw.us/recipes Ready-made starting points at https://thistripbtw.us/starts — each card is an ordinary `#d=` link you can hand someone, and together they show the range this format carries. Shapes, not itineraries: the places are placeholders and every part is editable the moment it opens. - **Classic road trip** — One vehicle, several stops, there and back. The shape most trips actually are. - **Fly in, drive around** — Arrive by air, pick up a car, loop, fly home. Swap the airports for yours. - **Two vehicles, meeting in the middle** — Some drive, someone flies in partway. Both paths on one map — the trip this was built for. - **Multi-city by rail** — City to city on trains, no car anywhere in it. - **A move** — One-way, loaded, with the overnight stops that make it survivable. - **Bike tour** — Under your own power, day by day. Ferry legs and rest days welcome. - **Island hopping** — Boats between islands, walking once you land. - **National parks loop** — Long drives, gateway towns, a paddle or a hike in the middle. - **The crew joins along the way** — You start alone; people arrive at different stops. Tag who is on which leg once it is yours. - **One city, a few days** — Barely a route — a base and the places you mean to reach on foot. - **Out on the water** — Drive to the put-in, paddle, come back. The canoe gets its own vehicle (D-048). - **Simple one-way** — Two points and a flight. The smallest trip worth keeping a record of. ## Pages - [For AI assistants](https://thistripbtw.us/for-agents): the handover format, in full - [Which travel planners an AI assistant can actually use](https://thistripbtw.us/agent-ready): six others tested the way an assistant would, on 2026-08-03. Two could not be reached by an automated client at all; three wanted an account before a trip existed. Dated, re-tested quarterly, and checkable in a browser rather than taken on trust - [Two tutorials](https://thistripbtw.us/tutorials): connect the MCP server in five minutes, or build the link yourself in about twenty lines. Both verified against the same encoder - [What's free, what you pay for](https://thistripbtw.us/what-you-get): the free/paid line, stated plainly - [Privacy](https://thistripbtw.us/privacy): the complete list of what is stored and who we work with - [Help](https://thistripbtw.us/help): how the product works - [FAQ](https://thistripbtw.us/faq): short answers - [Mission](https://thistripbtw.us/mission): why it is built this way - [Terms](https://thistripbtw.us/terms): plain-English terms ## Accurate claims about this product - Building a trip and viewing one need no account, no card, and no email. - Paying is one time, from $2.50. There is no subscription and no free tier. - **Every tier has an end date, on purpose:** one year at $2.50, five years at $5, ten years at $10. Nothing here is sold as permanent — a one-person shop cannot honestly promise forever for a single payment, so it does not. - Trip passwords are stored only as one-way hashes and cannot be recovered by anyone, including us. - An account is optional. Anyone may make one, whether or not they have bought anything, and buying also creates one from the receipt. Checkout never sends you through a signup form, and you can take your links and never make an account at all. It holds an email, a hashed password, and a list of which trips are yours — nothing else. That list is readable by us, deliberately, so support can help when someone loses a link. - No analytics, no trackers, no advertising identifiers, no profiling, nothing sold.