How Parlay Works
How Parlay maps Polymarket, Kalshi, Limitless, and Manifold into a single MCP research interface.
Doc index
Looking for a machine-readable map of every Parlay doc? See the
Introduction for the human version, or fetch
/docs/llms.txt for the agent-friendly index.
Parlay sits between an AI assistant and supported prediction-market venues. It turns venue-specific data into one typed MCP research interface, then returns structured results that the client can summarize and cite. The current MVP is read-only and covers Polymarket, Kalshi, Limitless, and Manifold.
The full pipeline
A user asks a question
Plain English in the AI client: "Find active markets about the next Fed decision" or "Compare similar election markets across venues."
The AI client picks a tool
The model reads Parlay's MCP descriptor, picks a tool such as search_markets, compare_markets, or market_brief, fills in typed arguments, and sends the call.
Parlay validates and routes
The MCP Worker checks the linked account, plan, quota, and tool access before routing the request to the right venue adapter.
The venue adapter calls upstream sources
Polymarket, Kalshi, Limitless, or Manifold returns its native payload. Parlay normalizes the shape so the client sees consistent field names, source links, timestamps, and caveats.
The client gets typed JSON back
The model receives structured fields it can reason about directly. No scraping, no venue-specific parsing logic, and no custom SDK in the AI client.
Layer 1: Your AI client
You bring the AI client. Parlay works with MCP-compatible clients as their connector support allows. The client provides:
| Capability | What it brings |
|---|---|
| Natural-language understanding | The model turns a plain-English market question into a real Parlay tool call. |
| Multi-step reasoning | The model can chain search, comparison, inspection, and briefing steps. |
| File and context grounding | The client can use documents, notes, dates, or themes you provide. |
| Human review | Parlay's MVP is read-only, so results stay in the research layer. |
| Result formatting | The model converts typed JSON into prose, tables, or source-linked summaries. |
Layer 2: MCP
MCP is the open protocol that lets compatible clients talk to tool servers without a custom SDK. Parlay exposes a hosted endpoint:
https://mcp.parlay.run/mcpThe descriptor handshake tells the client which tools exist and what shape each call takes.
Free tools
Free accounts include 15 calls per month with search_markets and market_brief.
Pro tools
Pro is planned at $29/month with all six tools and 150 calls per month once paid upgrades are enabled.
For the wire-level handshake and a sample descriptor, see How MCP Works. For the current tool list, see Tools.
Layer 3: Account mapping
Parlay uses website sign-in plus the MCP Worker install flow to link an MCP client to a Parlay account.
Sign in on Parlay
Open Sign In and authenticate with Google. The website session is handled by Better Auth.
Install Parlay in a client
Use the client guide for Claude or another supported MCP client. The install flow links the MCP connection to your Parlay account.
Worker maps the account
The MCP Worker stores the provider account mapping. The website dashboard can then check your MCP status, plan, and quota through an internal server-side request.
Plan and quota are enforced
Each tool call is checked against the linked account's plan. Free accounts can use the two free tools; paid access is enabled only when the payment flow is ready.
What Parlay does not ask you for:
- Wallet seed phrases or private keys
- Venue-side API secrets
- Custodial balances on any platform
- Passwords for supported venues
Layer 4: Venue adapters
The point of Parlay is that one tool shape works across multiple venues. Coverage varies by venue and by market availability.
| Parlay tool | Primary use | Venue notes |
|---|---|---|
search_markets | Find relevant markets by keyword, topic, venue, or tag. | Available across the primary venue set. |
discover_markets | Browse active market clusters before you know the query. | Availability depends on each venue's public data shape. |
compare_markets | Compare similar questions and settlement wording. | Best when multiple venues list comparable questions. |
scan_discrepancies | Surface notable differences for human review. | Most useful where comparable real-money markets exist. |
inspect_platform | Explain venue status, coverage, and known limitations. | Available for every supported venue page. |
market_brief | Produce a short research brief with caveats and sources. | Uses results from the other research tools. |
Manifold is useful for community sentiment and play-money context. Limitless coverage is tracked separately from Polymarket and Kalshi because venue wording, liquidity, and source availability can differ.
Safety model
Parlay is read-only today. The safety model is still layered because AI clients can make repeated tool calls quickly.
| Layer | Protection | Who enforces it |
|---|---|---|
| Account link | Tool calls are tied to the installed MCP account. | MCP Worker |
| Plan scope | Tool access follows Free, Pro, or Team plan rules. | MCP Worker |
| Rate limiting | Per-account quotas limit runaway client loops. | MCP Worker |
| Venue ToS | Adapters are designed around venue limits and acceptable-use rules. | Venue adapters |
| Data minimization | Tool responses return declared research fields and source references. | MCP Worker |
| Audit logging | Tool-call metadata can be retained for abuse prevention and support. | Parlay control plane |
Not investment advice
Parlay provides research context, source links, and venue caveats. It does not provide financial, legal, tax, or investment advice.
Data flow summary
| What | Where it lives | Who can access it |
|---|---|---|
| Website session | Better Auth session storage | The signed-in website user and Parlay auth services |
| Provider account link | Website database and MCP Worker account records | Parlay server-side services |
| Plan and quota status | MCP Worker | The dashboard through /api/me and the MCP Worker |
| Market data | Venue adapters and short-lived response processing | The requesting MCP client |
| Request metadata | Parlay control plane logs | Parlay support and abuse-prevention systems |
| Response payloads | Returned to the MCP client | The connected AI client and user |