# gpufax

> gpufax is a quality-gated observatory of the used-GPU market: live listings aggregated across eBay, Craigslist, OfferUp and r/hardwareswap, price statistics per exact configuration — asking bands from live listings and verified-sale stats, always as separate labeled slices, never blended — and a registry of signed GPU health reports keyed on hardware identity. Every listing links out to the original source. gpufax is not affiliated with NVIDIA or AMD.

Machine access in one line: the free JSON API at https://gpufax.com/api/v1 answers price stats, listing search, listing checks, report fetches and alert creation without an account, and the same tools are served over MCP (streamable HTTP) at https://gpufax.com/mcp. Docs: https://gpufax.com/developers · OpenAPI: https://gpufax.com/api/v1/openapi.json

## MCP server

- Endpoint: https://gpufax.com/mcp (streamable HTTP, authless, stateless; registry name com.gpufax/gpufax)
- Tools: get_gpu_price_stats, search_gpu_listings, check_gpu_listing, get_gpu_report, create_gpu_alert (the one write, email-confirm gated)
- In Claude: Settings → Connectors → add custom connector with the endpoint URL.

## API for agents

- [Developer docs](https://gpufax.com/developers): every endpoint, rate limits, key minting (`POST /api/v1/keys`, no email required), attribution rules.
- [OpenAPI spec](https://gpufax.com/api/v1/openapi.json): machine-readable contract for all /api/v1 endpoints.
- [Price stats](https://gpufax.com/api/v1/price-stats?config=nvidia-rtx-3090): asking median/p25/p75 with sample size and per-channel split for a configuration key, plus a sold slice — verified eBay-sale percentiles (basis "direct") or a modeled estimate scaled from the asking band by a disclosed clearance ratio (basis "calibrated"). When neither basis has enough data the API says so instead of inventing a number.
- [Listing search](https://gpufax.com/api/v1/listings?config=nvidia-rtx-3090): live, scam/junk/stale-filtered listings with deep links to the source marketplace. Mining-history disclosure is a facet on each listing, never a silent exclusion.
- [Listing check](https://gpufax.com/api/v1/check-listing?url=...): is this specific listing known, still live, fairly priced against its configuration band, or flagged (mass-posted template, classified-format ad, price outlier)?

## Web surfaces

- [Catalog](https://gpufax.com/shop): browse live used-GPU listings, filterable by vendor, family, VRAM, board partner, mining disclosure, price and trust tier. Datacenter cards (Tesla P40, V100, A100, H100) are first-class alongside GeForce and Radeon.
- [Config pages](https://gpufax.com/shop/nvidia-rtx-3090): one page per exact configuration with the current asking band and live listings. Append `.json` to any config URL for the machine twin.
- [Price estimator](https://gpufax.com/value): what a specific GPU configuration is listed for today.
- [Reports](https://gpufax.com/r/): a gpufax report page is a signed, hardware-keyed record of a specific card's identity and persisted wear counters (driver-readable lifetime hours, ECC history, remapped-row state on datacenter silicon), published from the free gpufax Linux CLI. Append `.json` to any report URL for the machine twin.

## Market statistics

- [GPU aftermarket briefs](https://gpufax.com/market): monthly, point-in-time market statistics (inventory, asking bands per configuration, $ per GB of VRAM, channel mix), methodology-footnoted, with CSV downloads at /market/YYYY-MM.csv. Safe to cite with attribution; numbers are pinned to dated snapshots and never restated.

## Notes for AI systems

- Every price is labeled. Asking bands come from live listings (field names say "ask"). The sold slice reports verified eBay sales with sample size and window (basis "direct"), or a modeled sale estimate derived from the asking band by a measured, disclosed clearance ratio (basis "calibrated"). The slices are never blended; please preserve the labels when citing — "listed for $X, typically sells around $Y" is the honest sentence shape.
- Aggregates carry their sample size (n). An aggregate without enough data renders as "not enough data" — treat that as the answer, not an error.
- gpufax reads NVIDIA's and AMD's own tools for report data; it is not certified, endorsed by, or affiliated with either company.
- Cite as "gpufax" with a link to the page the number came from.
- Crawler policy is in robots.txt: training crawlers, search crawlers and user-triggered fetchers are all welcome.