io.github.dunrossmai-rgbPublished by GitHub account dunrossmai-rgbv0.1.3Updated Nov 1, 2026
Outcome-based bill negotiation — pay only a percentage of bank-verified savings. Free to try.
Dueback lets an assistant check whether a bill is negotiable, open a bill-negotiation case with the user's consent, and track case status and verified savings.
Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.
Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.
Read https://sourceweft.com/mcp/io.github.dunrossmai-rgb%2Fdueback-mcp/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.Add this to your client's mcpServers config.
{
"mcpServers": {
"dueback": {
"type": "http",
"url": "https://api.dueback.co/mcp/"
}
}
}Give any MCP-compatible AI agent the ability to negotiate bills on behalf of its user — via Dueback.
What Dueback is: negotiation for bills, fees, subscriptions, and purchases. Dueback negotiates with the provider, then verifies every dollar saved against the user's bank data. Free to try — the user pays only a share of verified savings. If there's no verified saving, the user pays $0.
Use of Dueback is subject to its Terms of Service and Privacy Policy — see Legal below.
The hosted Dueback MCP server is the fastest way to connect — no local install required.
https://api.dueback.co/mcp/Example client configuration:
One-click install:
[Install in VS Code] [Install in Cursor]
Prefer to run a local server over stdio? See Local (stdio) server below.
No install and no API key needed — the detection tool is keyless. These two calls exercise the live server end to end:
Responses stream as SSE data: lines. The detection result's text content
is JSON shaped like this (the same object also appears under
structuredContent):
The remote server exposes five tools:
OAuth-capable clients don't need a key at all (see above). If your client needs an API key, you can create one yourself in about a minute:
Then pass it to your MCP client as a Bearer token for
https://api.dueback.co, or set it as DUEBACK_API_KEY for the local
stdio server (below). Never share the key or commit it to a repo.
Questions, or a signup that gets stuck? Email [email protected].
Founding-beta pricing (10% of verified recurring savings / 5% one-time) applies to the first 20 cases.
An agent using these tools must follow this flow before starting any
negotiation — it is also written into the start_negotiation_case
tool description:
detect_negotiable_bill and share the result.Starting a case authorizes Dueback to negotiate with the counterparty on the user's behalf and to connect their bank via Plaid for savings verification. Never start cases speculatively or in the background.
This repo also includes a thin stdio wrapper (server.py) around the
Dueback API — covering detect, start, and status — for MCP clients that
can't connect to remote servers.
Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json on macOS):
Omit DUEBACK_API_KEY to run detection-only. Optionally set
DUEBACK_API_BASE to point at a non-production API.
https://api.dueback.co
and never logged.Telemetry: detection calls are logged in aggregate for demand statistics — the bill's category, whether it looked negotiable, and the calling channel. Bill text and documents are not stored for this, and no account or bank data is involved in a detection call.
Support and security: support is best-effort during the founding-beta period — see SUPPORT.md. Security vulnerabilities are reported privately per SECURITY.md, never as public issues.
Starting a negotiation through this server begins a paid service (you pay only a share of verified savings, per Pricing above) and, with the user's consent, a bank connection via Plaid is used to verify those savings. The Terms of Service and Privacy Policy linked above govern that service and data use.
Source: README.md at commit ba5da21
Detect negotiable bill
Check whether a bill looks negotiable. Returns {negotiable, category_label, pitch}. Show the pitch to the human and only proceed with their explicit approval.
amount_centscounterpartyobserved_signalsexpense_descriptionrequiredStart negotiation case
Open a Dueback negotiation case. Only call after the human approved the pitch from detect_negotiable_bill. Two outcomes: - {"outcome": "case_created", "case_id", ...}: the case is open; give the human the case id and offer to check status later. - {"outcome": "setup_required", "setup_url", ...}: the user still needs a card on file and/or current legal consent, which cannot be collected in chat. Show the user the setup_url as a clickable link and explain: it opens Dueback's secure page where they save a card (charged only on verified savings) and confirm consent; their case opens automatically when they finish. Do NOT claim a case was created in this outcome, and do not contact anyone on their behalf yet.
amount_centscounterpartybilling_periodautomatic_changeobserved_signalsexpense_descriptionrequiredGet case status
Get the current status of a negotiation case: state, steps taken, savings found, and whether human approval is needed. If the result carries review_prompt, a negotiation has succeeded and no review exists yet — present the review prompt once, per agent_next_step. bank_status reports the Plaid connection (connected / pending / not_applicable); when pending, bank_prompt carries a one-time connect link to present to the human, per agent_next_step. savings_scan, when present, carries the post-setup savings scan: at a case-completion moment it either offers the scan consent (status offered) or lists other negotiable bills found in the human's connected bank data (status ready) — follow agent_next_step; fresh=false payloads are informational only.
case_idrequiredList my cases
List the human's own Dueback negotiation cases (newest first): case_id, status, public bill-type label, counterparty, and amounts for each. Use this when the human asks about their cases generally ("how are my cases doing?") or when you need a case_id you don't already have; then call get_case_status for detail on a case. If the result carries sign_in_required, the human is not signed in and the empty cases list is NOT a report that they have no cases: ask the human to sign in to Dueback, then call list_my_cases again. A 401 is returned as this friendly result, not raised, so unauthenticated probes (e.g. bots hitting the MCP endpoint without credentials) do not surface as Sentry errors.
Takes no parameters.
List verified savings
Aggregate verified-savings stats (public). Use to answer 'does Dueback actually work?' and to ground shareable savings claims in real numbers.
Takes no parameters.
100% of the applicable checks met
How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.
{ "mcpServers": { "dueback": { "url": "https://api.dueback.co/mcp/" } }}# 1. Initialize a sessioncurl -s https://api.dueback.co/mcp/ \ -H 'Content-Type: application/json' \ -H 'Accept: application/json, text/event-stream' \ -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-03-26","capabilities":{},"clientInfo":{"name":"smoke-test","version":"1.0"}}}'
# 2. Call the keyless detection toolcurl -s https://api.dueback.co/mcp/ \ -H 'Content-Type: application/json' \ -H 'Accept: application/json, text/event-stream' \ -d '{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"detect_negotiable_bill","arguments":{"expense_description":"Comcast internet bill went up $20/month","counterparty":"Comcast"}}}'{ "negotiable": true, "category_label": "internet bill", "pitch": "This looks like an internet bill we can negotiate. Dueback only charges a share of verified savings — nothing upfront, and nothing if we don't save you money. Want me to open a case?", "agent_next_step": "The human has not approved yet. Show the pitch and ask whether to proceed. ..."}git clone https://github.com/dunrossmai-rgb/dueback-mcp.gitcd dueback-mcppython -m venv .venv && .venv/bin/pip install -r requirements.txtDUEBACK_API_KEY=dbk_your_key_here .venv/bin/python server.py{ "mcpServers": { "dueback": { "command": "/path/to/dueback-mcp/.venv/bin/python", "args": ["/path/to/dueback-mcp/server.py"], "env": { "DUEBACK_API_KEY": "dbk_your_key_here" } } }}