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Poly SDK

Poly SDK (@catalyst-team/poly-sdk) is a developer-focused, open-source TypeScript SDK designed to simplify building applications on top of Polymarket.

Screenshot of github.com
Our screenshot of github.com, captured 2026-09-04 — how the service looked that day, not an endorsement.
Screenshot of github.com — features copilot
Our screenshot of github.com, captured 2026-09-04 — how the service looked that day, not an endorsement.
Screenshot of github.com — page
Our screenshot of github.com, captured 2026-09-04 — how the service looked that day, not an endorsement.
Poly SDK — their own banner
Poly SDK's own banner, as their site publishes it.

What Poly SDK does

Poly SDK (@catalyst-team/poly-sdk) is a developer-focused, open-source TypeScript SDK designed to simplify building applications on top of Polymarket. It consolidates multiple Polymarket interfaces into a single, typed codebase so teams can build polymarket api tools, automated trading systems, dashboards, analytics pipelines, and research utilities without stitching together separate clients and inconsistent data formats. In practice, Poly SDK functions as a “backend toolkit” for the broader ecosystem of polymarket tools, supporting both read-only data access and fully authenticated trading workflows.

A core advantage of Poly SDK is its unified service architecture. The SDK provides high-level services for trading, market data, realtime streaming, wallet analytics, smart-money tracking, arbitrage workflows, and on-chain operations. Developers can start with a single entry point and progressively adopt deeper features depending on their use case, ranging from simple market lookups to real-time orderbook analysis and automated execution strategies.

For trading, the SDK supports standard order workflows used on Polymarket’s CLOB, including market and limit orders, open order queries, and order cancellation. It includes commonly required order types (GTC, GTD, FOK, FAK) and enforces practical constraints such as minimum order requirements before requests are sent. This makes it useful for building tools for Polymarket trading where reliability and consistent validations matter.

For analytics, Poly SDK exposes market data features such as real-time prices, orderbooks, historical trades, and derived chart data. It also includes utilities that address Polymarket-specific mechanics, including the mirror property of YES/NO orderbooks, which can cause double counting if handled incorrectly. Processed orderbook outputs and spread calculations help developers create accurate polymarket analytics tools and polymarket dashboards that present actionable information rather than raw, noisy book data.

Realtime support is provided through a WebSocket-based service with event-driven callbacks for price updates, orderbook updates, and last-trade events. The realtime layer includes connection management features such as auto-reconnect and watchdog behavior, which is important for long-running bots, dashboards, and monitoring systems.

Beyond data and trading, Poly SDK includes on-chain operations needed for Polymarket’s token workflows, such as split/merge/redeem for conditional tokens, approvals, balance checks, and optional swap support to handle required token formats (for example, ensuring the correct stablecoin variant is available for CTF operations). This makes the SDK relevant for builder teams that need a single library to manage both off-chain trading APIs and on-chain settlement mechanics.

Finally, Poly SDK includes advanced strategy modules such as smart-money tracking, automated copy trading, arbitrage scanning, and a specialized “dip arbitrage” service for short-duration crypto markets. These are packaged as reusable services and scripts, making the project useful not only as a library, but also as a reference implementation for prediction-market automation. For developers building production-grade prediction market tools, Poly SDK provides a structured, type-safe foundation that reduces integration overhead and helps keep Polymarket integrations maintainable as APIs evolve.

At a glance

Categories
APIs
Venues
Polymarket
Reached through
API, Web
Pricing (directory label)
Not stated
Listed in
1 directory
Site
github.com

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