Monday's agreement also suggests the Obama administration would rather reach compromises on such disclosures than wait to see whether courts or Congress order more far-reaching transparency measures.
The pact on disclosures focuses specifically on the government's scrutiny of Internet traffic, and doesn't apply to the phone-records program that also has been the subject of intense debate since Mr. Snowden's revelations. It aims to strike a balance between the companies' desires to say more about government searches and the government's interest in not having the details of such requests revealed in a way that would tip off targets of investigations.

Among the biggest changes under the agreement: For the first time, companies can disclose how many court orders they receive from the Foreign Intelligence Surveillance Court, a specialized tribunal for national-security matters whose decisions typically are secret.
Also, companies can give out more information about National Security Letters they 
receive from the Federal Bureau of Investigation, an area where some disclosure already was permitted. And they may say in general terms how many customer accounts are involved, a disclosure that could help the companies fight back against perceptions that huge numbers of customers are affected by government surveillance.

"If the assumption is those secret programs are widespread, that causes customers of technology companies to lose trust in those technology companies," said Matthew Prince, chief executive of CloudFlare Inc., a San Francisco cybersecurity company.
Mr. Prince said the agreement may not do much to alleviate the concern that the NSA's reach is "broad and far-reaching."Many big tech firms say the government spying revelations are hurting their businesses not just among American consumers but also overseas, where they are trying to expand.