About HaggleBoard
HaggleBoard Protocol (HBP) is a category-agnostic negotiation message specification for AI shopping agents, enabling buyers and sellers to negotiate through signed requests, offers, counters, and decisions. It connects agreements to existing checkout rails without handling money; the repository includes the spec, JSON Schemas, and a rule-based demo that needs no API keys.
Key features
- 01Define six negotiation message types
- 02Negotiate prices with signed messages
- 03Provide hotel, electronics, and B2B extensions
- 04Validate schemas, nonces, and expirations
- 05Run a rule-based demo without API keys
Use cases
- 01Let shopping agents negotiate hotel rates
- 02Negotiate offers for open-box electronics
- 03Agree on prices before B2B supply contracts
MCP support
The input mentions MCP as a way for agents to find products, but does not say that HaggleBoard itself provides an MCP server or connects to MCP clients.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://haggleboard.com/mcpclaude mcp add --transport http com-haggleboard-haggleboard https://haggleboard.com/mcp{"mcpServers":{"com-haggleboard-haggleboard":{"type":"http","url":"https://haggleboard.com/mcp"}}}Open in Cursor{"servers":{"com-haggleboard-haggleboard":{"type":"http","url":"https://haggleboard.com/mcp"}}}Open in VS Code{"mcpServers":{"com-haggleboard-haggleboard":{"type":"http","url":"https://haggleboard.com/mcp"}}}{"mcpServers":{"com-haggleboard-haggleboard":{"serverUrl":"https://haggleboard.com/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
Details
From the project READMEHaggleBoard Protocol (HBP) v0
Pitch. AI agents can already find products (MCP), talk to each other (A2A) and pay (UCP, ACP, AP2), but no open standard lets them agree a price. HaggleBoard is that missing layer: a small, category-agnostic set of signed messages (Request, Offer, Counter, Accept, Decline, Expire) so any buyer agent can negotiate with any seller agent: a hotel room tonight, an open-box laptop, or a 12-month B2B supply contract. Once both sides agree, the signed deal token goes straight into existing checkout rails. HBP never touches money and charges no fees. It is the handshake that comes before the payment, and it aims to be for agent deal-making what HTTP is for the web.
Contents
SPEC.md: the v0 spec in plain English, with examplesschemas/: JSON Schemas (draft 2020-12) for the 6 messages and 3 category extensions (hotel, electronics, b2b)demo/haggle_demo.py: one shopper agent and two seller agents with private floor prices, haggling a hotel stay and a laptopdemo/sample_transcript.txt: output from a real run with--recording(seller floors and shopper ceilings are never printed; run without the flag locally to see them)
Run
pip install cryptography # jsonschema optional; a built-in checker is used if absent
python3 demo/haggle_demo.py
The agents are rule-based and need no API keys. Every message is checked against its schema, offers and counters are signed with Ed25519, and nonces and expiry are enforced. The demo also shows that a replayed message, a tampered price and an expired offer are all rejected.
Status: draft v0.
License
Code and schemas: Apache-2.0 (LICENSE). Spec text: CC-BY-4.0 (LICENSE-docs). Patent non-assert: PATENTS.md. See NOTICE.
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.