PolyBridge MCP

PolyBridge MCP gives Claude Desktop probabilistic foresight from live prediction markets.

Ask a question about the future, even when no exact market exists. PolyBridge finds relevant markets, synthesizes the evidence, and returns a read-only forecast with probabilities and source-market metadata.

No API key is required at anonymous limits. Add POLYBRIDGE_API_KEY only for higher usage.

PolyBridge MCP is read-only. It does not trade or move funds.

Tools

PolyBridge MCP exposes two read-only tools:

• polybridge_search
• polybridge_forecast

Both tools are read-only. They do not place trades, submit orders, handle custody, or perform write actions.

Search

polybridge_search retrieves relevant prediction markets for a topic or question.

• Search results return ranked prediction-market retrieval results.
• Scores are relevance/ranking scores, not probabilities.
• Local MCPB Search works without POLYBRIDGE_API_KEY at anonymous limits.
• Configure POLYBRIDGE_API_KEY only for higher usage.
• If dimensions is omitted, Search uses all supported dimensions by default: direct, upstream, downstream, and correlated.

Forecast

polybridge_forecast generates read-only forecasts using PolyBridge market search and evidence synthesis.

• Forecast responses return forecast outputs and probabilities.
• Local MCPB Forecast works without POLYBRIDGE_API_KEY at anonymous limits.
• Configure POLYBRIDGE_API_KEY only for higher usage.
• A search_forecast key can power both Search and Forecast.

Non-goals

PolyBridge MCP does not provide:

• trading
• orders
• payments
• sessions
• market history
• market lookup
• Situation Rooms
• internal APIs
• custody
• write actions

Installation

1. Download polybridge-mcp-v0.2.6.mcpb from the polybridge-mcp-v0.2.6 GitHub Release for this repository. Release: https://github.com/crowdvector/polybridge-mcp/releases/tag/polybridge-mcp-v0.2.6
2. Open or import the file in Claude Desktop.
3. Enable the extension.
4. No API key is required at anonymous limits for Search and Forecast. Configure POLYBRIDGE_API_KEY only for higher usage.

Basic Usage

Ask Claude:

Use PolyBridge Search to find active prediction markets related to US recession risk.

Or:

Use PolyBridge Forecast to estimate the probability of a US recession in 2026.

API Key Configuration

• Local MCPB Search and Forecast work without POLYBRIDGE_API_KEY at anonymous limits.
• Configure POLYBRIDGE_API_KEY in the Claude Desktop extension settings only for higher usage.
• Invalid configured auth fails hard and does not fall back to anonymous.
• Use the PolyBridge Developer Console to create a Search+Forecast key.
• A search_forecast key can power both tools.
• Do not paste API keys into chat.

Search Limits

Anonymous / local with no key:

• top_k_per_dimension <= 20
• dimensions <= 4

With POLYBRIDGE_API_KEY:

• top_k_per_dimension <= 50
• dimensions <= 4

Supported Search Dimensions

• direct
• upstream
• downstream
• correlated

REST API

The public REST API supports Search and Forecast without an API key at anonymous limits. Add an API key for higher usage.

• Search: https://api.polybridge.ai/v1/search
• Forecast: https://api.polybridge.ai/v1/forecast

Hosted MCP

Hosted MCP is available at https://mcp.polybridge.ai/mcp. No API key is required at anonymous limits. Add an API key or supported OAuth for higher usage. Invalid configured auth fails hard and does not fall back to anonymous.

Support

For higher usage or access questions, contact the PolyBridge team.