Yahoo is to make APIs (application programming interfaces) available for external developers so they can build tools for Yahoo's Panama search-advertising platform.

Available under the Yahoo Search Marketing Commercial API Program, the APIs are available to anyone. Yahoo's Panama APIs are designed primarily for Yahoo search advertisers, ad agencies, search-marketing consultants and commercial application developers, Yahoo said yesterday.

Yahoo wants such companies to develop complementary tools and applications that will enhance their use and their clients' use of Panama for tasks such as designing, deploying, tracking, managing and refining search marketing campaigns.

Yahoo has high hopes that Panama will help boost revenue from search engine advertising, a market dominated by rival Google.

Yahoo maintains that Panama significantly improves on its ability to match ads to search queries, and is convinced that this improved targeting will increase the number of times users click on its search engine pay-per-click ads.

While ad-serving enhancements are certainly important for Yahoo to improve its position against Google, Panama doesn't directly address the other big component of search wars: user popularity.

Google still draws significantly more users to its search engines than Yahoo does, so Google's ads are seen by more people and as such are more likely to get clicked.

In April, US users ran almost half of all queries through Google's search engines, while Yahoo processed almost 27 percent, according to comScore Networks.

In total numbers, this means that Google had 3.6 billion queries on its search engines and Yahoo 2 billion. Thus, in addition to improving its ad system, Yahoo needs to cut that popularity gap if it wants to significantly raise its search ad revenue.

Different levels of access to the Panama APIs exist, both free and fee-based. More details are on the Yahoo search-advertising API website.