decide.fyi

Decision API + MCP notaries for deterministic system and agent decisions

One-Click Install

Buttons install the Refund Notary server. To add all 4 servers, use the JSON config below.

MCP Servers

All servers: 100 vendors, US region, individual plans, stateless, no auth, 100 req/min.

Quick Start

Connect via MCP (Claude Desktop / Windsurf / other clients)

{
  "mcpServers": {
    "refund-decide": { "url": "https://refund.decide.fyi/api/mcp" },
    "cancel-decide": { "url": "https://cancel.decide.fyi/api/mcp" },
    "return-decide": { "url": "https://return.decide.fyi/api/mcp" },
    "trial-decide":  { "url": "https://trial.decide.fyi/api/mcp" }
  }
}

REST API

# Refund eligibility
curl -X POST https://refund.decide.fyi/api/v1/refund/eligibility \
  -H "Content-Type: application/json" \
  -d '{"vendor":"adobe","days_since_purchase":12,"region":"US","plan":"individual"}'

# Cancellation penalty
curl -X POST https://cancel.decide.fyi/api/v1/cancel/penalty \
  -H "Content-Type: application/json" \
  -d '{"vendor":"adobe","region":"US","plan":"individual"}'

# Return eligibility
curl -X POST https://return.decide.fyi/api/v1/return/eligibility \
  -H "Content-Type: application/json" \
  -d '{"vendor":"adobe","days_since_purchase":12,"region":"US","plan":"individual"}'

# Trial terms
curl -X POST https://trial.decide.fyi/api/v1/trial/terms \
  -H "Content-Type: application/json" \
  -d '{"vendor":"adobe","region":"US","plan":"individual"}'

Local Dev Checks

Start local dev server:

npx vercel dev

In a separate terminal:

# Handler-level smoke checks (no running server required)
npm run smoke

# MCP endpoint checks (requires vercel dev running on localhost:3000)
npm run mcp:check

# End-to-end workflow fixture (example -> result)
npm run workflow:test

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Zendesk Workflow Orchestrators

Use workflow endpoints when you want one request to return:

• decision classification (yes | no | tie) from /api/decide
• policy result from the relevant notary endpoint
• recommended Zendesk action + tags + private note with request_id

Endpoints

• POST https://refund.decide.fyi/api/v1/workflows/zendesk/refund
• POST https://cancel.decide.fyi/api/v1/workflows/zendesk/cancel
• POST https://return.decide.fyi/api/v1/workflows/zendesk/return
• POST https://trial.decide.fyi/api/v1/workflows/zendesk/trial

Request

{
  "ticket_id": "ZD-9001",
  "workflow_type": "refund",
  "question": "Should this Adobe annual plan refund request proceed under policy?",
  "vendor": "adobe",
  "region": "US",
  "plan": "individual",
  "days_since_purchase": 5
}

For refund and return, include days_since_purchase.

Deterministic test mode

Set decision_override to bypass model classification during fixtures and CI:

{
  "decision_override": "yes"
}

Response (example)

{
  "ok": true,
  "flow": "zendesk_refund_v1",
  "ticket_id": "ZD-9001",
  "decision": { "c": "yes", "request_id": "req_123" },
  "policy": { "verdict": "ALLOWED", "code": "WITHIN_WINDOW" },
  "action": {
    "type": "approve_refund",
    "zendesk_tags": ["decide", "decide_yes", "refund_allowed"]
  }
}

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Refund Notary

Endpoint: POST https://refund.decide.fyi/api/v1/refund/eligibility MCP Tool: refund_eligibility

Checks if a subscription purchase is within the vendor's refund window.

Input: vendor, days_since_purchase, region, plan

{"refundable":true,"verdict":"ALLOWED","code":"WITHIN_WINDOW","message":"Refund is allowed. Purchase is 12 day(s) old, within 14 day window.","vendor":"adobe","window_days":14}

Codes: WITHIN_WINDOW, OUTSIDE_WINDOW, NO_REFUNDS, UNSUPPORTED_VENDOR

Cancel Notary

Endpoint: POST https://cancel.decide.fyi/api/v1/cancel/penalty MCP Tool: cancellation_penalty

Checks cancellation penalties — early termination fees, contract locks, or free cancellation.

Input: vendor, region, plan

{"verdict":"PENALTY","code":"EARLY_TERMINATION_FEE","message":"adobe charges an early termination fee: 50% of remaining months on annual plan.","vendor":"adobe","policy":"etf"}

Codes: NO_PENALTY, EARLY_TERMINATION_FEE, CONTRACT_LOCKED, UNSUPPORTED_VENDOR

Return Notary

Endpoint: POST https://return.decide.fyi/api/v1/return/eligibility MCP Tool: return_eligibility

Checks if a subscription purchase can be returned/reversed, with return type and method.

Input: vendor, days_since_purchase, region, plan

{"returnable":true,"verdict":"RETURNABLE","code":"FULL_RETURN","message":"Return is available. Purchase is 5 day(s) old, within 14-day window.","vendor":"adobe","return_type":"full_refund","method":"self_service"}

Codes: FULL_RETURN, PRORATED_RETURN, CREDIT_RETURN, OUTSIDE_WINDOW, NO_RETURNS, UNSUPPORTED_VENDOR

Trial Notary

Endpoint: POST https://trial.decide.fyi/api/v1/trial/terms MCP Tool: trial_terms

Checks free trial availability, length, card requirement, and auto-conversion status.

Input: vendor, region, plan

{"verdict":"TRIAL_AVAILABLE","code":"AUTO_CONVERTS","message":"adobe offers a 7-day free trial. Credit card required. Auto-converts to paid plan.","vendor":"adobe","trial_days":7,"card_required":true,"auto_converts":true}

Codes: AUTO_CONVERTS, NO_AUTO_CONVERT, TRIAL_NOT_AVAILABLE, UNSUPPORTED_VENDOR

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Supported Vendors (100)

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