Yahoo has established a fee structure for the upcoming version of BOSS, a platform that developers use to create custom search engines on top of Yahoo's infrastructure.
The top-tier option, called Full Web, includes result links to general Web pages, images and news articles, and will cost $US0.80 per 1,000 queries, Yahoo said on Tuesday.
A less expensive tier, Limited Web, will draw its results from a smaller index that isn't refreshed as often as the one Full Web uses and costs $0.40 per 1,000 queries.
Yahoo will also offer developers options for an image-only index ($0.30 per 1,000 queries) and for a news article-only index ($0.10 per 1,000 queries).
"Each query will return a predetermined number of results. Developers will be charged for queries received by Yahoo based on the applicable price for query type, and be billed on a monthly basis, or more frequently, depending on a developer's query volume," wrote Rahul Hampole, from the BOSS team, in a blog post.
Yahoo plans to provide technical documentation on what it calls BOSS V2 by March 1 before rolling it out during the summer. There will also be requirements for developers to display Yahoo brands on their BOSS-based search engines.
BOSS, which stands for Build Your Own Search Service, is aimed at developers of all sizes, including individuals, startups and large companies.
Yahoo will provide guidance and assistance to developers interested in running search and display ads on their search engines. "Our goal is to provide a product that allows you to build sustainable businesses via interesting cloud-based search technology at a fair cost. In addition, we encourage BOSS developers to monetize your products using Yahoo Search advertising," he wrote.
Yahoo originally announced in October of last year that the previously free BOSS would shift to a fee-based model in 2011. At the time, Yahoo also said that access to the platform would be based on the oAuth protocol and that it would provide lower-cost options for schools and nonprofit groups.
As part of its search deal with Microsoft, Yahoo is transitioning its back-end search infrastructure to Bing, on which BOSS will also eventually run. The transition is expected to be complete next year.
The search deal calls for Yahoo to depend on Bing for Web crawling, site indexing and result matching and ranking, and it is already doing so in North America.
Yahoo will also rely on Microsoft for self-service sales of pay-per-click text search ads. Yahoo will be in charge of premium, guaranteed-placement search ads, while also handling relationships with big advertisers, search-marketing firms, resellers and their clients.