# Behalf (PXP v0) [Health: Active]

**Category:** 🤝 Agreements & Coordination  
**Repository:** https://github.com/JulesNsenda/behalf  
**GitHub Stars:** 0  
**Views:** 1  
**Installs:** 0  
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**Directory Page:** https://allmcps.com/mcp/behalf-pxp-v0

## Description
Negotiate for your human under PXP: tagged claims, escalation, decision brief, hash-chained ledger

## Tools
Capabilities this server exposes over MCP:

- **create_room** — Open a new room. Your principal takes seat A, and you get a private invite link for the other person (seat B). Send the invite only to that person. Use this when your principal wants to negotiate with someone and has no room yet. This server requires sign-in: your MCP client must send your principal's agent key as an Authorization: Bearer header (not as an argument). Your principal gets a key at https://behalf.dropkit.sh/key. No passcode is needed. counterpart_proxy "builtin" also needs "Use our AI" access, which your principal asks for at https://behalf.dropkit.sh/start; without it, use "external".
- **join_room** — Take your principal's seat with their private link. Returns the room state, your principal's card (if sealed), and what to do next.
- **seal_intent_card** — Seal your principal's Intent Card. Only after they confirmed every line. Once sealed it cannot change except through escalation answers.
- **get_room** — Current state from your seat: status, whose turn, transcript, claims you still need to review, unverified assumptions, and the next action.
- **wait_for_turn** — Blocks up to timeout_seconds (max 25) until it is your turn, your principal must answer a question, or the room ends. Call it again if it times out.
- **send_envelope** — Send one PXP envelope on your turn. The server enforces the rules: untagged or unreferenced claims become "assumed", agreeing while raising a conflict is refused. The enforced envelope is returned.
- **answer_escalation** — When the room is paused for your principal, ask them the question verbatim and relay their exact answer. It is sealed into their card as an amendment. Never answer on their behalf.
- **get_brief** — The decision brief once the room has ended: agreed terms, authority per term, unverified assumptions, escalations, ledger head.

## Claude Desktop Quick Installation
Remote MCP endpoint (confidence: high). Install path detected from listing signals. Add as a URL/SSE server in your client:

```json
"mcpServers": {
  "behalf-pxp-v0": {
    "url": "https://behalf.dropkit.sh/mcp"
  }
}
```

## Documentation

## What Behalf (PXP v0) does

Behalf (PXP v0) implements version 0 of the Proxy Exchange Protocol, in which two AI proxies negotiate on behalf of two people. The protocol requires claims to carry one of three labels: stated, sourced, or assumed. When a proxy reaches its configured limit, the negotiation can be escalated to the corresponding human.

An agreement produces two records: a decision brief describing the outcome and a hash-chained ledger containing the negotiation history. The repository also includes a browser-based flow for creating rooms, inviting another participant, conducting the conversation, and viewing the resulting brief.

## How it works

The Node.js application exposes an MCP endpoint at `/mcp`. An MCP-capable agent can connect to that endpoint and take a seat in a negotiation room. The protocol core handles envelope enforcement, sealing, and ledger operations, while the proxy implementation supports Claude-backed participants.

Rooms can use the built-in Claude proxies when an Anthropic API key is configured, or they can accept a user-provided agent. The repository includes a scripted demonstration of a hallucination cascade that runs without an API key, so the basic protocol flow can be examined without calling Anthropic.

## Setup and configuration

The application runs on Node.js 20 or newer. `PORT` controls the listening port, `BIND_HOST` controls the address, and `PUBLIC_URL` supplies the base URL used in links given to agents. The MCP route is `/mcp` on that server.

Set `ANTHROPIC_API_KEY` to enable the built-in Claude proxies, card drafting, and the authority audit. `PXP_MODEL` selects the proxy model and defaults to `claude-sonnet-5-5`. Without the API key, the demo and bring-your-own-agent rooms remain available.

Storage can remain in a local `rooms.json` file or use Postgres by setting `DATABASE_URL`. When durable storage is enabled through the documented data-directory or database settings, `SIGNIN` must also be configured. GitHub sign-in requires `GITHUB_CLIENT_ID` and `GITHUB_CLIENT_SECRET`; local operation defaults to sign-in off.

## Tools and capabilities

The Behalf (PXP v0) MCP server provides access to protocol-driven negotiation rather than a general-purpose API. Its documented capabilities include:

- Joining a negotiation through the MCP endpoint
- Enforcing protocol envelopes and sealing messages
- Marking claims as stated, sourced, or assumed
- Escalating decisions to human participants
- Producing decision briefs for agreements
- Maintaining a hash-chained negotiation ledger
- Sending email through a development outbox or SMTP when configured

The web application also provides room creation, invitations, agreement viewing, agent-key creation, and administration for requests to use the hosted AI.

## Limitations and notes

The implementation is explicitly for PXP v0. Built-in proxy behavior depends on Anthropic access, while the demo does not. Proxy rooms stop after `MAX_TURNS`, which defaults to 10. Live and demo rooms are removed after their configured inactivity periods, and the server enforces room, account, and address limits.

Postgres support requires a direct or session-mode connection rather than a transaction pooler. SMTP mode requires the documented host, port, sender, TLS, and authentication settings. The development mail transport writes messages to an outbox and does not deliver them on the hosted platform.

The repository contains the protocol schemas and a copy of the specification, but identifies the separate `JulesNsenda/pxp` repository as the canonical specification source.

_Full upstream README: https://allmcps.com/mcp/behalf-pxp-v0/readme_