v19 (latest stable)

Status

Live May 11, 2026

Summary

This stable release adds Klima Protocol carbon liquidity and prices to the Carbonmark API which is now multi-network aware supporting Polygon and Base.

Release notes

General

• Added retire support for Klima Protocol carbon class credits.

• Removed legacy Polygon-specific explorer URL fields from order and retirement payload models, standardizing on chain-agnostic explorer URLs.

• Updated API info limits to be chain-specific instead of a single shared value.

Endpoints removed

• None

Endpoints updated

GET /info

• [⚠️BREAKING CHANGE] Response shape changed:

  • Removed MAX_USDC

  • Added POLYGON_MAX_USDC

  • Added BASE_MAX_USDC

POST /orders ; GET /orders ; GET /orders/:id

• [⚠️BREAKING CHANGE] Removed polygonscan_url from order response model

• Use on_chain_explorer_url instead for both Polygon and Base transactions

GET /retirements ; GET /retirements/:id

• [⚠️BREAKING CHANGE] Removed polygonscanUrl from retirement response model

• Use onChainExplorerUrl instead for both Polygon and Base transactions

Endpoints added

• None

New optional query parameters

• GET /carbonProjects

  • assetPriceType

• GET /carbonProjects/:id

  • assetPriceType

• GET /prices

  • minPriceUSD

  • assetPriceType

The assetPriceType filter lets you narrow results to projects with specific pricing sources. Accepted values are listing (seller listings on Carbonmark) and klimaprotocol (Klima protocol pool prices).

Migration Path

• Order response

  • If you were using polygonscan_url, migrate to on_chain_explorer_url

• Retirement response

  • If you were using polygonscanUrl, migrate to onChainExplorerUrl

• /info

  • Replace reads of MAX_USDC with chain-specific handling:

    • POLYGON_MAX_USDC for Polygon retirements

    • BASE_MAX_USDC for Base retirements