[1][2] Vox has described Semafor as "a collection of newsletters, plus a website, aimed at an upscale audience that understands topics like Washington politics and Silicon Valley tech but wants more".

The website is free to access and supported by advertisements, though Semafor's co-founders have described plans to convert to a paid subscription model.

According to The New York Times, "semaphore" is "often used in a nautical context" and can be described as "a visual signaling apparatus often involving flags, lights and arm gestures".

[5] In a memo Justin Smith sent to "close confidants", he described a new company that would "reimagine quality global journalism" aimed at what he said was an "English-speaking, college-educated, professional class" that had "lost trust in all sources of news and information".

[12] In July 2024, Semafor launched a Middle East vertical, adding a third world region to its existing coverage of the United States and sub-Saharan Africa.

[6] Genesis Motor/Hyundai Motor Company, Mastercard, Pfizer, Qualcomm, the Indian multinational conglomerate Tata Group, and Verizon were among ten founding launch partners.

[4][24] Initial hires included Reed Albergotti of The Washington Post, Liz Hoffman of The Wall Street Journal,[6][25] and Max Tani of Politico, who would focus on technology, business and finance, and media, respectively.

[2] Other common sections include "The View From," which describes perspectives from countries or parties involved in the story, and "Room for Disagreement," which explores why the writer's analysis may be wrong.

Each newsletter contains a regular feature called "One Good Text" in which journalists conduct one-question interviews with politicians, business executives, or other influential[according to whom?]

[14] Even before launching, Semafor had already held 12 events,[28] including one in July 2022 with Tucker Carlson and Taylor Lorenz that focused on polarization and trust within the news industry,[29] and another in November 2022 called "Media, Government, and a Healthy Democracy" with Karine Jean-Pierre and Anthony Scaramucci.

The event featured interviews with Rwandan president Paul Kagame,[31] U.S. trade representative Katherine Tai,[32] and Qin Gang, China's ambassador to the U.S.[14][27] Subsequent events included a "media summit" in April 2023 in New York City with Barry Diller,[33] Chris Licht, Jen Psaki,[34] Stephen A. Smith, and Kara Swisher,[27][35] and a "World Economy Summit" in Washington, D.C., in April 2023 with National Economic Council director Lael Brainard[36][37] and Microsoft president Brad Smith.

Other advisors include Chen Deming, a former Minister of Commerce; Cui Tiankai, a former Chinese ambassador to the U.S.; and Zhou Xiaochuan, a former governor of People's Bank of China.

Lee Chair in U.S.–Asia Relations at the Harvard Kennedy School; John L. Thornton, former co-president of Goldman Sachs; and David Rubenstein, a philanthropist, investor, and former Deputy Assistant to the President for domestic policy.