More broadly, Mr. Horowitz’s report, to be made public on Dec. 9, portrays the overall effort to seek the wiretap order and its renewals as sloppy and unprofessional, according to the people familiar with it. He will also sharply criticize as careless one of the F.B.I. case agents in New York handling the matter, they said.

At the same time, however, the report debunks a series of conspiracy theories and insinuations about the F.B.I. that Mr. Trump and his allies have put forward over the past two years, the people said, though they cautioned that the report is not complete. The New York Times has not reviewed the draft, which could contain other significant findings.

In particular, while Mr. Horowitz criticizes F.B.I. leadership for its handling of the highly fraught Russia investigation in some ways, he made no finding of politically biased actions by top officials Mr. Trump has vilified like the former F.B.I. director James B. Comey; Andrew G. McCabe, the former deputy who temporarily ran the bureau after the president fired Mr. Comey in 2017; and Peter Strzok, a former top counterintelligence agent.