# btw (remote · btw.space)

Agentic group buying. Agents pool demand into chains that clear at a group price. Waitlist is open.

- Trust score: 66/100 (medium)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-09-20

## Components

- remote · `btw.space`: 66/100 (this document), [markdown](https://verifymcp.io/servers/space-btw-btw/btw.md), [page](https://verifymcp.io/servers/space-btw-btw/btw)

## Channel facts

- Endpoint: `https://btw.space/mcp?utm_source=mcp-registry`
- Transports: `streamable-http`
- Auth: `none`
- Version: `2.1.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-09-20.

- **Endpoint Security**: 46/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation check failed: no authorisation is required to call this server, and it exposes a tool marked destructive (release).
  - HTTPS enforcement could not be verified: the plaintext port answered with HTTP 406, which proves neither a plaintext path nor enforcement.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 67/100
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 2281 tokens (~126/item across 18 items; 18 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 60/100
  - Stability observed for 18 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 94/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 81% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 18 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 19 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### How do I install the btw MCP server?

btw is a hosted endpoint at https://btw.space/mcp?utm_source=mcp-registry, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add --transport http space-btw-btw 'https://btw.space/mcp?utm_source=mcp-registry'
```

### Cursor

```json
{
  "mcpServers": {
    "space-btw-btw": {
      "url": "https://btw.space/mcp?utm_source=mcp-registry"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "space-btw-btw": {
      "type": "http",
      "url": "https://btw.space/mcp?utm_source=mcp-registry"
    }
  }
}
```

### Codex

```toml
[mcp_servers.space-btw-btw]
url = "https://btw.space/mcp?utm_source=mcp-registry"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "space-btw-btw": {
      "type": "remote",
      "url": "https://btw.space/mcp?utm_source=mcp-registry",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add space-btw-btw --url 'https://btw.space/mcp?utm_source=mcp-registry' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  space-btw-btw:
    url: "https://btw.space/mcp?utm_source=mcp-registry"
```

### Netclaw

```json
{
  "McpServers": {
    "space-btw-btw": {
      "Transport": "http",
      "Url": "https://btw.space/mcp?utm_source=mcp-registry"
    }
  }
}
```

### Vellum

```bash
assistant mcp add space-btw-btw -t streamable-http -u 'https://btw.space/mcp?utm_source=mcp-registry'
```

### Other

```json
{
  "mcpServers": {
    "space-btw-btw": {
      "type": "http",
      "url": "https://btw.space/mcp?utm_source=mcp-registry"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-09-19 (score 66, 0)

- [security] Tool “hold” rewrote its description, which is the text the model reads
- [security] Tool “join” rewrote its description, which is the text the model reads
- [cosmetic] “hold” added an optional parameter “ref”
- [cosmetic] “join” added an optional parameter “ref”

### 2026-09-18 (score 66, +1)

- [security] The server rewrote its instructions, which are the text every model session reads
- [security] New tool “release”, which the server declares destructive
- [security] Tool “book_stats” rewrote its description, which is the text the model reads
- [security] Tool “get_chain” rewrote its description, which is the text the model reads
- [security] Tool “join” rewrote its description, which is the text the model reads
- [security] Tool “join_chain” rewrote its description, which is the text the model reads
- [security] Tool “leave” rewrote its description, which is the text the model reads
- [security] Tool “list_chains” rewrote its description, which is the text the model reads
- [security] Tool “park” rewrote its description, which is the text the model reads
- [security] Tool “park_intent” rewrote its description, which is the text the model reads
- [security] Tool “status” rewrote its description, which is the text the model reads
- [security] Tool “waitlist” rewrote its description, which is the text the model reads
- [functional regression] Schema quality: 1966 → 2233
- [functional] New tool “hold”
- [cosmetic] “join” reworded the description of “chain”
- [cosmetic] “join” reworded the description of “invite_code”
- [cosmetic] “join” reworded the description of “max_price_usd”
- [cosmetic] “join” reworded the description of “name”
- [cosmetic] “leave” reworded the description of “chain”
- [cosmetic] “status” reworded the description of “chain”
- [cosmetic] “status” reworded the description of “email”
- [cosmetic] “waitlist” reworded the description of “email”
- [cosmetic] “join” made “chain” optional
- [cosmetic] “join” made “invite_code” optional
- [cosmetic] “join” made “max_price_usd” optional
- [cosmetic] “status” made “chain” optional
- [cosmetic] Tool “join” changed its title: Join a chain → Hold a spot (old name)
- [cosmetic] Tool “leave” changed its title: Leave a chain → Release a spot (old name)

### 2026-09-16 (score 65, +1)

- [security] The server rewrote its instructions, which are the text every model session reads
- [security] Tool “list_chains” rewrote its description, which is the text the model reads
- [functional regression] Schema quality: pass → fail
- [functional improvement] Tool coverage: 58% → 80%
- [functional] Server version: 2.1.0 → 2.3.0
- [functional] New tool “sync_wishlist”
- [functional] New tool “want”
- [functional] New tool “want_gym”
- [functional] New tool “want_home”
- [functional] New tool “want_software”
- [functional] New tool “want_stay”

### 2026-09-15 (score 64, +1)

No change was recorded against any check on this day. Stability & Change Management went from 40 to 43. That category is still filling its 30-day observation window: 12 days of observed history at the previous scan, 13 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-12 (score 63, +1)

No change was recorded against any check on this day. Stability & Change Management went from 30 to 33. That category is still filling its 30-day observation window: 9 days of observed history at the previous scan, 10 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-10 (score 62, +1)

No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-08 (score 61, +1)

No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-06 (score 60, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

## MCP tools (18)

### `waitlist` (~125 tokens)

Join the waitlist

Old style: put your human on the list to hear when the next product goes live. Prefer want with a link, or hold on what's live. Needs their email. Optionally say what they want to buy and which agent platform you are.

Input parameters:

- `email` (string): your human's email
- `platform` (string): your agent platform, like claude, grok, chatgpt, other
- `referral` (string): a friend's referral code or link, if you came through one
- `want` (string): what your human wants to buy, plainly

### `list_chains` (~40 tokens)

List chains

Every product btw has run or queued: the live one, what's up next by wants, and what filled or closed. Use status for the live one.

### `hold` (~215 tokens)

Hold a spot

Hold your human a spot on the live product. Needs their email. Returns the price this spot locks and a link where they save a card; the spot is held once they do. The first spots lock at the early price; every spot after locks at the group price. The result says which one this spot got. Nothing is charged now. If the product fills, the deposit is charged and applied to their purchase; they pay the balance to the brand. If it doesn't fill, nobody pays. Stripe test mode. Test cards only, no real money moves.

Input parameters:

- `chain` (string): a product slug; leave it out for what's live
- `email` (string, required): your human's email
- `invite_code` (string): not needed any more
- `max_price_usd` (number): optional cap on the deposit in dollars
- `name` (string): first name and last initial, shown on the product page
- `ref` (string): a referral code from another buyer's link, the r= part

### `join` (~221 tokens)

Hold a spot (old name)

The old name for hold. Hold your human a spot on the live product. Needs their email. Returns the price this spot locks and a link where they save a card; the spot is held once they do. The first spots lock at the early price; every spot after locks at the group price. The result says which one this spot got. Nothing is charged now. If the product fills, the deposit is charged and applied to their purchase; they pay the balance to the brand. If it doesn't fill, nobody pays. Stripe test mode. Test cards only, no real money moves.

Input parameters:

- `chain` (string): a product slug; leave it out for what's live
- `email` (string, required): your human's email
- `invite_code` (string): not needed any more
- `max_price_usd` (number): optional cap on the deposit in dollars
- `name` (string): first name and last initial, shown on the product page
- `ref` (string): a referral code from another buyer's link, the r= part

### `status` (~94 tokens)

Chain status

What's live: the product, its list and group price, how many buyers unlock the price, how many are committed, how many want it, spots left, and the deadline if one is set. Give a slug to ask about another product, and an email to also see that person's spot.

Input parameters:

- `chain` (string): a product slug; leave it out for what's live
- `email` (string): check this person's spot

### `release` (~64 tokens)

Release a spot

Release a held spot. Needs the product slug, the email that holds it, and the commitment id from hold or status. Nothing is charged for a released spot.

Input parameters:

- `chain` (string, required): product slug
- `commitment_id` (string, required)
- `email` (string, required)

### `leave` (~70 tokens)

Release a spot (old name)

The old name for release. Release a held spot. Needs the product slug, the email that holds it, and the commitment id from hold or status. Nothing is charged for a released spot.

Input parameters:

- `chain` (string, required): product slug
- `commitment_id` (string, required)
- `email` (string, required)

### `park` (~77 tokens)

Park a want

Old style: park what your human wants in plain words with the most they'd pay. Prefer want with a link.

Input parameters:

- `description` (string, required): what your human wants, plainly
- `email` (string): optional, so we can say when a chain opens
- `max_price_usd` (number, required): the most they'd pay, in dollars

### `want` (~372 tokens)

Want a product

Say your human wants something. Takes a link or an ASIN plus their email. A hotel link becomes a stay want (give month, and nights if known), a subscription link becomes a software want (give plan), anything else is gear. Or set type and the fields outright: stay needs hotel and month, home needs job and zip, software needs product and plan. Records the want and returns the item with how many others already want it. If you already read a page yourself, pass asins instead of a link. A new email also joins the waitlist. btw doesn't buy from Amazon. The link is how we know what you want; the group price comes from the brand.

Input parameters:

- `asin` (string): an Amazon ASIN, 10 letters and digits
- `asins` (array): ASINs you read off a page yourself, up to 100
- `email` (string, required): your human's email, same as the waitlist
- `hotel` (string): stay: hotel name or link
- `job` (string): home: solar, home-battery, ev-charger, heat-pump, roof, windows, sauna-install, other
- `month` (string): stay: month as YYYY-MM
- `name` (string): gym: the gym or studio name
- `nights` (integer): stay: nights, if known
- `note` (string): home or stay: a short note
- `plan` (string): software: individual, family, team, other
- `product` (string): software: product name or link
- `type` (string): skip auto-detection and say the type
- `url` (string): a product, hotel, or subscription link
- `zip` (string): home: five digit US zip

### `sync_wishlist` (~188 tokens)

Sync an Amazon wishlist

Read a public wishlist and record every item as a want for your human. Amazon wishlists and Steam wishlists. Takes the list link plus their email. Returns the items found and how many others want each one. If the server can't read the list, the reply says so; then open the list yourself and pass the ASINs, or call want once per product link. A new email also joins the waitlist. btw doesn't buy from Amazon. The link is how we know what you want; the group price comes from the brand.

Input parameters:

- `asins` (array): ASINs you read off the list yourself, up to 100
- `email` (string, required): your human's email, same as the waitlist
- `url` (string): the list link. Amazon: open the list, tap Share, copy the link. Steam: the profile's wishlist page

### `want_stay` (~133 tokens)

Want a stay

Your human wants a hotel in a given month. Takes the hotel (name or link), the month as YYYY-MM, nights if known, and their email. People wanting the same hotel in the same month count together; when enough do, btw asks the hotel for a group rate. Returns how many others want it.

Input parameters:

- `email` (string, required): your human's email, same as the waitlist
- `hotel` (string, required): hotel name or a link to it
- `month` (string, required): month as YYYY-MM
- `nights` (integer): nights, if known
- `note` (string)

### `want_home` (~137 tokens)

Want a home job

Your human wants a home job done: solar, home-battery, ev-charger, heat-pump, roof, windows, sauna-install, other. Takes the job, their five digit zip, an optional note, and their email. Homes near each other wanting the same job count together; when enough do, btw gets a group quote from local installers. Returns how many others nearby want it.

Input parameters:

- `email` (string, required): your human's email, same as the waitlist
- `job` (string, required): the job
- `note` (string): anything the installer should know
- `zip` (string, required): five digit US zip

### `want_software` (~109 tokens)

Want a subscription

Your human wants a software subscription at group pricing. Takes the product (name or link), the plan (individual, family, team, other), and their email. Annual plans; vendors already have volume tiers and btw brings the volume. Returns how many others want the same product on the same plan.

Input parameters:

- `email` (string, required): your human's email, same as the waitlist
- `plan` (string, required): the plan
- `product` (string, required): product name or a link to it

### `want_gym` (~118 tokens)

Want a gym or studio membership

Your human wants a membership at a gym or studio near them. Takes the name, their five digit zip, the plan (monthly, annual, class-pack, other), and their email. People near the same gym on the same plan count together; when enough do, btw asks for a group rate.

Input parameters:

- `email` (string, required): your human's email, same as the waitlist
- `name` (string, required): gym or studio name
- `plan` (string, required): the plan
- `zip` (string, required): five digit US zip

### `book_stats` (~26 tokens)

Book stats

Counts at a glance: live, queued, filled. Use status for the live product.

### `get_chain` (~25 tokens)

Get one chain

One product by slug. Prefer status.

Input parameters:

- `id` (string, required): chain slug

### `join_chain` (~43 tokens)

Join a chain (old name)

The old v1 join. Use hold instead.

Input parameters:

- `id` (string)
- `monthly_commit_usd` (number)
- `team_name` (string)

### `park_intent` (~62 tokens)

Park a standing order (old name)

The old v1 park. Use want with a link instead.

Input parameters:

- `category` (string)
- `min_discount_pct` (number)
- `monthly_cap_usd` (number)
- `note` (string)
- `provider` (string)

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/space-btw-btw/btw#diagnostics

## Score history

- 2026-09-20: 66
- 2026-09-19: 66
- 2026-09-18: 66
- 2026-09-17: 65
- 2026-09-16: 65
- 2026-09-15: 64
- 2026-09-14: 63
- 2026-09-13: 63
- 2026-09-12: 63
- 2026-09-11: 62
- 2026-09-10: 62
- 2026-09-09: 61
- 2026-09-08: 61
- 2026-09-07: 60
- 2026-09-06: 60
- 2026-09-05: 59
- 2026-09-04: 59
- 2026-09-03: 58
- 2026-09-02: 58

## Common questions

### What is the btw MCP server?

btw is an MCP server listed in the public MCP registry as space.btw/btw. Agentic group buying. Agents pool demand into chains that clear at a group price. Waitlist is open. This page covers its hosted endpoint (https://btw.space/mcp?utm_source=mcp-registry).

### Is the btw MCP server safe to use?

btw scores 66 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the btw MCP server expose?

btw exposes 18 tools: waitlist, list_chains, hold, join, status, and 13 more. Their descriptions and schemas cost roughly 2,119 tokens of context every time the server is loaded.

### Does the btw MCP server require authentication?

No. We connected to btw without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

### Is the btw MCP server still maintained?

btw is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

## Links

- Remote endpoint: https://btw.space/mcp?utm_source=mcp-registry
- Website: https://btw.space/
- Changelog RSS feed: https://verifymcp.io/servers/space-btw-btw/btw.xml
- Changelog JSON feed: https://verifymcp.io/servers/space-btw-btw/btw.json
- HTML version of this page: https://verifymcp.io/servers/space-btw-btw/btw