API changelog

Everything new in the Old Cars Data API and MCP server: new endpoints, added sources, improvements, and fixes. We ship continuously and post notable changes here.

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  1. v1.8

    New API docs and changelog

    The API reference is easier to use, with clearer endpoint pages, examples, and a changelog for product-facing release notes.

    • Improved

      Reworked the docs navigation so teams can quickly jump between REST endpoints, MCP setup, live auctions, bid history, stats, makes, and models.

    • Improved

      Added clearer request examples and response guides for developers building valuation tools, market monitors, and AI workflows.

    • New

      Published this changelog as the public place to track notable API, MCP, and data-access updates.

  2. v1.7

    Expanded OpenAPI reference

    The OpenAPI spec now covers the current API surface for teams that generate clients, validate integrations, or connect developer tooling.

    • Improved

      Documented live auctions, auction bids, richer auction result fields, validation errors, rate limits, and response examples in OpenAPI 3.1.

    • Improved

      Added OpenAPI coverage for VIN lookup, seller username lookup, keyword search, source filters, sort direction, and pagination.

    • Fixed

      Clarified the separation between completed auction results and active live listings, so customers can choose the right endpoint for each workflow.

  3. v1.6

    Live auctions and bid history beta

    Bring a Trailer live inventory and bid trails are now available as separate beta surfaces for polling, watchlists, and market monitoring.

    • Beta

      Added GET /auctions/live with filters for make, model, VIN, seller, source, keyword, year, price, ending window, updated_since, sorting, and pagination.

    • Beta

      Added GET /auctions/{auction_id}/bids for paginated bid history with bid time, amount, bidder name, currency, and date filters.

    • Improved

      Expanded MCP access with live auction and bid-history tools so connected AI clients can inspect active listings and bid ladders.

  4. v1.5

    Hosted MCP server for AI tools

    Claude, Cursor, ChatGPT, and other MCP-compatible tools can connect directly to Old Cars Data instead of relying on pasted exports or manual lookup.

    • New

      Added hosted MCP tools for list_makes, list_models, search_auctions, list_live_auctions, list_auction_bids, and market stats.

    • New

      Added OAuth-aware connection support for AI clients that need scoped, authenticated access to market data.

    • Improved

      MCP requests now follow the same account plan and usage rules as REST API requests, making agent workflows predictable for teams.

  5. v1.4

    Public API reference

    Developers can now inspect the API contract directly and use refreshed docs for authenticated REST access.

    • New

      Added the /openapi.json route with production server metadata and bearer-auth documentation.

    • Improved

      Refreshed getting-started, auctions, stats, makes, models, and MCP docs with endpoint-specific examples.

    • Improved

      Improved API error responses so failed requests are easier to diagnose during integration.

  6. v1.3

    Clearer plan access

    API access now has clearer plan behavior, so teams know which endpoints and result windows are available on their account.

    • Improved

      Standardized plan limits across REST API and MCP access.

    • Improved

      Starter users get bounded result windows for exploratory use, while paid plans can access broader result sets.

    • Fixed

      Improved authorization messages for missing, invalid, or plan-limited API access.

  7. v1.2

    Richer auction result payloads

    Auction search responses now carry more of the normalized listing details needed for valuation workflows and UI previews.

    • New

      Added featured_image_url and expanded vehicle fields across auction response schemas and docs.

    • Improved

      Returned structured modifications, known flaws, recent service history, listing details, bid counts, watcher counts, and normalized colors where available.

    • Fixed

      Renamed the primary image field to featured_image_url for clearer listing previews.

Build with the API

Explore the full API reference

Endpoints, authentication, request examples, and the MCP server: everything you need to integrate the collector-car market.

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