# Best Buy Developer API vs Walmart Affiliate Marketing API

> Best Buy Developer and Walmart Affiliate Marketing score within a point of each other for product search for shoppers, 39.1 and 38.6 out of 100. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/best-buy-vs-walmart-affiliate-api
- Markdown: https://www.anchorterminal.com/compare/best-buy-vs-walmart-affiliate-api.md (~2,100 tokens)
- Slim: https://www.anchorterminal.com/compare/best-buy-vs-walmart-affiliate-api.min.md (~730 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/best-buy-vs-walmart-affiliate-api.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-14

Best Buy Developer API and Walmart Affiliate Marketing API score within a point of each other on agent readiness, 39.1 (E) and 38.6 (E). Walmart Affiliate Marketing API leads on security & auth and transparency & trust. Both do product search for shoppers.

- Best Buy Developer API: grade E, 39.1/100, rank #991 of 1076. Markdown https://www.anchorterminal.com/tools/best-buy.md · JSON https://www.anchorterminal.com/api/v1/tools/best-buy.json
- Walmart Affiliate Marketing API: grade E, 38.6/100, rank #995 of 1076. Markdown https://www.anchorterminal.com/tools/walmart-affiliate-api.md · JSON https://www.anchorterminal.com/api/v1/tools/walmart-affiliate-api.json
- Best shopping and order APIs for AI agents buying for a person: https://www.anchorterminal.com/best/shopping/index.md
- All 8 shopping comparisons: https://www.anchorterminal.com/compare/shopping/index.md

## Which one, for what

### Best Buy Developer API (E)

Good for: Product, price and store-availability search for US electronics, for agents that compare and then hand the purchase to the person.

Ahead on:
- Schema & documentation, 45 against 27
- Agent ergonomics, 72 against 57
- Payments & pricing, 30 against 25

Watch for: Ordering, fulfilment, order lookup and cancellation are only in the Commerce API, which is invite-only with documentation shared after approval

### Walmart Affiliate Marketing API (E)

Good for: Product search and affiliate links for an agent recommending Walmart products and handing the purchase to the person.

Ahead on:
- Security & auth, 58 against 32
- Transparency & trust, 53 against 47

Watch for: No order, cart, order status or return operation in the affiliate API


## Score by category

| Category | Weight | Best Buy Developer API | Walmart Affiliate Marketing API | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 31 | 33 | Walmart Affiliate Marketing API +2 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 45 | 27 | Best Buy Developer API +18 |
| Agent ergonomics | 13% (16.2 this run) | 72 | 57 | Best Buy Developer API +15 |
| Security & auth | 14% (17.5 this run) | 32 | 58 | Walmart Affiliate Marketing API +26 |
| Payments & pricing | 10% (12.5 this run) | 30 | 25 | Best Buy Developer API +5 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 5 | 5 | even |
| Transparency & trust | 7% (8.8 this run) | 47 | 53 | Walmart Affiliate Marketing API +6 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **39.1 · E** | **38.6 · E** | |

## Facts side by side

| Fact | Best Buy Developer API | Walmart Affiliate Marketing API |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | BestBuy.com, LLC (Best Buy Co., Inc.) | Wal-Mart.com USA, LLC (Walmart Inc.) |
| Hosted endpoint | `https://api.bestbuy.com/v1/` | `https://developer.api.walmart.com/api-proxy/service/affil/product/v2` |
| Transports | HTTP | HTTP |
| Auth | API key | API key |
| Pricing | Free | Free |
| x402 | no | no |
| Licence | Proprietary service under the Best Buy Developer API terms. The SDKs in the BestBuyAPIs GitHub organisation are open source | Proprietary service under the Walmart I/O API Terms of Use (last updated 30 September 2020) |
| Read-only variant documented | no | yes |
| llms.txt | no | no |
| Terms last updated | 2021-02-23 | 2026-09-09 |
| Privacy policy last updated | couldn't be read | 2026-08-20 |
| Customer content may train models | not found in the text | yes |
| Terms restrict automated access | not found in the text | yes |
| Terms restrict benchmarking | yes | not found in the text |
| Terms or service can change without notice | yes | yes |
| Arbitration or class-action waiver | yes | yes |
| Popularity | 489 npm/wk | none |

## Verdicts

**Best Buy Developer API.** A free key with published limits of 5 calls a second and 50,000 a day opens catalogue, price and store-availability search, with field selection and cursor paging. Ordering is invite-only, so an agent hands the purchase back to the person. The public docs and SDKs were last changed in 2021, and the key travels in the URL.

**Walmart Affiliate Marketing API.** Live, free catalogue search and product lookup for approved Walmart affiliates, signed with an RSA key and capped at 5,000 calls a day. It cannot place or follow orders, and the Checkout API needs separate approval. The documentation renders only in a browser, and the API terms date from 2020 and still name a previous affiliate network.

## Before you call either

### Best Buy Developer API

1. Add format=json to Products, Stores and Categories calls. XML is the default for those three
2. Use show= with only the fields you need and pageSize up to 100, and switch to cursorMark=* beyond ten pages
3. Batch SKU lookups with the in operator to stay under 5 calls a second. A 403 can mean the limit, not a bad key
4. Send the person to the product URL to buy. The Commerce API that places orders needs a partner invitation
5. Cache responses for no more than 72 hours and refresh prices before quoting them, as the terms require

### Walmart Affiliate Marketing API

1. Generate a fresh WM_SEC.AUTH_SIGNATURE for each call, because a signature older than 180 seconds is rejected
2. Keep below 5,000 calls a day per application
3. Pass the Impact publisher ID so returned links earn commission
4. Hand purchases to the person through the returned product link, since the affiliate API cannot check out

## Questions

### Which is better for AI agents, Best Buy Developer API or Walmart Affiliate Marketing API?

Best Buy Developer API and Walmart Affiliate Marketing API score within a point of each other on agent readiness, 39.1 (E) and 38.6 (E). Walmart Affiliate Marketing API leads on security & auth and transparency & trust.

### Do Best Buy Developer API and Walmart Affiliate Marketing API need an API key?

Both need an API key.

### Can an agent call Best Buy Developer API and Walmart Affiliate Marketing API without installing anything?

Yes. Best Buy Developer API has a hosted endpoint at https://api.bestbuy.com/v1/ and Walmart Affiliate Marketing API at https://developer.api.walmart.com/api-proxy/service/affil/product/v2.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/best-buy-vs-walmart-affiliate-api.json, and with the fewest tokens: https://www.anchorterminal.com/compare/best-buy-vs-walmart-affiliate-api.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "best-buy", "b": "walmart-affiliate-api"}`. From a terminal: `anchor compare best-buy walmart-affiliate-api`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/best-buy.json and https://www.anchorterminal.com/api/v1/tools/walmart-affiliate-api.json

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