SDKs & wrapperslibraryfree
@polymarket/clob-client-v2: what it does, what it costs, where it stops
Last checked 2026-09-08
@polymarket/clob-client-v2 is Polymarket's official TypeScript client for the CLOB v2, with py_clob_client_v2 as the Python sibling. Both repos are MIT, active and still publishing (npm 1.1.0, PyPI 1.1.0), and both READMEs open with a note recommending the unified ts-sdk or py-sdk for new projects. The TypeScript repo has 74 stars and the Python repo 167.
They are for developers who want a thin wrapper over the order book API and nothing else, or who maintain code written against the archived original clob-client and py-clob-client.
What it does
Two authentication levels. L1 is a wallet signature (EIP-712) used to create or derive API credentials; L2 is HMAC with the resulting key, secret and passphrase, required for order placement, cancellation and account data. The TypeScript client takes a viem wallet client as signer and supports Chain.POLYGON or Chain.AMOY for testnet.
createAndPostOrder places resting GTC limit orders; createAndPostMarketOrder places FOK or FAK market orders with an amount in USDC. Tick size is passed per order. Errors return as objects by default or throw an ApiError with status and data when throwOnError is set.
The Python README mirrors the TypeScript one: ClobClient(host, chain_id, key) derives credentials with create_or_derive_api_key(), then a second ClobClient with creds places orders through create_and_post_order with OrderArgs and PartialCreateOrderOptions(tick_size). Chain ID 137 is Polygon and 80002 is the Amoy testnet.
- npm @polymarket/clob-client-v2: 26 versions since March 1, 2026, updated September 8, 2026.
- PyPI py-clob-client-v2: 1.1.0 published July 17, 2026, 8 releases since April 8, 2026, Python 3.9.10 or newer.
- The original Polymarket/clob-client (514 stars) and py-clob-client (1,234 stars) repos were archived on May 25, 2026.
Pricing
Free under MIT in both languages.
Venues and data
Polymarket CLOB only. Gamma (market metadata) and the Data API are outside its scope, which is the main reason the unified SDK exists.
Where it falls short
It is superseded by its own maintainers. The docs migration guide tells TypeScript users to uninstall clob-client-v2 along with builder-relayer-client and builder-signing-sdk and install @polymarket/client instead. Expect maintenance to taper.
No WebSocket, no market discovery and no wallet abstractions: you supply the token ID, the tick size and the signer yourself. Both READMEs leave the CLOB host as a placeholder to fill from docs.polymarket.com, and neither documents rate limits or how to find a token ID; those live in the API reference.
Who should use it
Existing integrations that already run on it and do not need new features, and minimal bots that only post and cancel orders. The archived originals stopped at 514 and 1,234 stars, so a large share of existing Polymarket bot code was written against them, and v2 is the smallest step from that code.
Everyone else starting today should use @polymarket/client or polymarket-client.
Questions about @polymarket/clob-client-v2
Is clob-client-v2 deprecated?
Not archived, but superseded. Its README recommends Polymarket/ts-sdk for new projects and the docs migration guide moves users to @polymarket/client.
What is the difference between clob-client and clob-client-v2?
The original clob-client and py-clob-client repos were archived on May 25, 2026. The v2 clients target the CLOB v2 API and are the ones still receiving releases.
Is there a Python version of clob-client-v2?
Yes. py_clob_client_v2 on PyPI (1.1.0) from the Polymarket/py-clob-client-v2 repo, with the same L1 and L2 authentication model.
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