White House Chief of Staff John F. Kelly talks with others before President Trump awards the Medal of Honor at the White House on July 31. (Jabin Botsford/The Washington Post)

White House Chief of Staff John F. Kelly has a new evening routine: He periodically strolls the perimeter of the White House grounds late at night, inspecting the compound and chatting with Secret Service agents to see if they have what they need.

Just two months into his new post, Kelly has expanded his portfolio to include issues large and small throughout the administration — from influencing personnel staffing at the agencies to vetting President Trump’s reading materials to his periodic nighttime walks along the White House fence line to check security.

The no-task-too-small leadership style — dating to Kelly’s training in the Marine Corps, where he rose to a four-star general — has its benefits for a president who often sows chaos in his wake, implementing a sense of order and discipline in a White House known for lacking both.

But it also has prompted grumbling about micromanaging within the West Wing, where some staffers complain that Kelly may be growing his mandate too far and that his strict regimen stifles the creativity and spontaneity that have been hallmarks of Trump’s enterprises. As one of Kelly’s subordinates put it, the chief of staff sometimes becomes “a one-man choke point.”

This portrait of Kelly’s management style is based on interviews with more than a dozen senior administration officials and Republicans close to the White House.

Since taking the helm of Trump’s embattled White House at the end July, Kelly has executed a number of structural and procedural changes to help tame what for months had been an unpredictable turbulence inside the West Wing.

Kelly has required that Ivanka Trump, the president's oldest daughter, go through him first when she wants to speak with her father about anything involving the administration, a requirement she has so far followed. In the run-up to the United Nations General Assembly in New York this week, a number of foreign governments and organizations reached out to her to set up meetings — all of which she ran by Kelly and his team before adding them to her schedule.

Kelly also has sought to clearly define the roles and portfolios of White House staff, especially at the highest levels. Under Kelly’s tenure, anyone with the top title — assistant to the president — must have a clear realm of responsibility.

Some jobs are more obvious; Hope Hicks, the new communications director, runs point on communications strategy. But other senior staffers — such as Reed Cordish and Chris Liddell of the Office of American Innovation, who both work with Jared Kushner, the president’s son-in-law and senior adviser, on long-term domestic policy initiatives — have more amorphous positions, and Kelly is trying to more clearly define their roles.

"I think the best chiefs in history have taken an expansive view of the job," said Chris Whipple, author of "The Gatekeepers," a history of White House chiefs of staff. But, he added: "It can be a problem if you obsess over the minutiae. A good chief of staff has to be able to delegate."

Kelly has helped oversee the administration’s handling of three successive hurricanes, which has earned Trump plaudits. But also on Kelly’s watch, the president has engulfed himself in a number of controversies and failures — including his equivocal response to the deadly white supremacist rally in Charlottesville and his pardoning of polarizing former Maricopa County, Ariz., sheriff Joseph Arpaio.

There is also little evidence that Kelly’s arrival has tamed the president’s impulses. This week alone, the president nicknamed North Korean leader Kim Jung Un “Rocket Man,” declared mounting evidence that Russia interfered in the 2016 election a “hoax” and continued to attack his former Democratic foe, Hillary Clinton.

“I still think the jury is out whether Kelly has what it takes to walk into the Oval Office, close the door behind him and tell Donald Trump what he doesn’t want to hear,” Whipple said.

Kelly’s militaristic style is seen as a virtue by many in the White House. On Air Force One flights and at a hotel restaurant in Arizona, Kelly has insisted that he be served last, after the rest of his team has received their food. During one meeting on the plane, he wordlessly delivered an extra order of fries from the galley for an aide who had been hungrily eyeing a co-worker’s order.

Gone are the days when someone can waltz into the Oval Office armed with specious data and attempt to manipulate the president’s thinking on an issue. People hoping to talk to Trump about policy have to submit an official request, which includes having their briefing materials vetted and fact-checked in advance.

“He’s been a great addition to the administration and been very helpful in promoting more responsibility with each staffer and a greater level of accuracy and accountability,” said Sarah Huckabee Sanders, the White House press secretary. “He is a great ­servant-leader who complements the president.”

KT Cole, 70, who lives in Troy, Ala., said he served with Kelly at Camp Lejeune in North Carolina in the early 1970s and recalled him as one of the finest men he had ever met, the sort of Marine who inspired even his superiors to follow his lead.

“He was tough, he was fair, but you knew not to mess with him,” Cole said, recalling the 67-year-old man he repeatedly described as a “good boy” and “good kid.”

The fact that Kelly joined Trump’s administration, Cole added, makes him feel more comfortable about the way the White House is being run. “You would rather tie a knot in a polecat’s butt than try to get John Kelly to do something he doesn’t want to do,” he said.

Kelly’s critics, however, say that his efforts to carefully vet the information Trump receives has led the president to consume less conservative media in his daily news diet — which has left him out of touch with his base.

“Donald Trump faces a full-scale revolution from his base,” said an editor at Breitbart, a conservative website, speaking on the condition of anonymity to offer a more candid assessment. “The base is furious with the president, thanks to the misinformation that his staff — who all have their own agenda that is not in line with the president’s agenda — are feeding him.”

Kelly’s arrival also has empowered a coterie of adept enforcers and protectors. Chief among them is Kirstjen Nielsen, Kelly’s principal deputy and gatekeeper. She is joined by Robert Porter, the staff secretary who oversees the policy process and the information flow in and out of the Oval Office, and Joseph Hagin, a veteran of the George W. Bush White House who as deputy chief of staff has taken control of the president’s schedule and operations.

Nielsen, who arrived at Kelly’s side and had no history in Trump’s campaign, has alienated some staffers while implementing a new level of discipline. But in recent weeks, she has been on something of a charm tour, reaching out directly to colleagues and cultivating alliances.

Kelly also has forged a close partnership with members of the national security team such as Defense Secretary Jim Mattis and national security adviser H.R. McMaster, an Army lieutenant general and military strategist who had feuded with former chief White House strategist Stephen K. Bannon.

In his first senior staff meeting, Kelly made clear that any policy issues on Capitol Hill must all run through Marc Short, Trump’s director of legislative affairs, who had previously seen his authority undermined by conflicting messages from within the West Wing. When staff circumvented Short, Kelly offered scoldings.

Kelly often joins calls between Trump and congressional leaders and occasionally will call a lawmaker for a follow-up conversation to ensure that everyone is on the same page.

Kelly also follows closely what his boss sometimes derides as the “fake news” media, urging his communications team to proactively work with reporters from mainstream organizations. In a few instances where a publication has reported friction between him and another West Wing staffer, Kelly has declared at staff meetings — sometimes playfully — that the aide in question remains in good standing.

Unlike his predecessor, Reince Priebus, who was a fixture on the Sunday television talk-show circuit, Kelly tries to keep a low public profile. His portrait appeared on the cover of Time magazine on Aug. 21, under the headline “Trump’s Last Best Hope,” but Kelly has yet to sit for a major media interview. His few interactions with journalists have been off-the-record in group sessions.

In moments when Trump engages with the media, such as at his Charlottesville news conference last month at Trump Tower in New York, Kelly stands purposefully out of view of the main cameras. At that event, however, one journalist captured Kelly’s tense, bowed expressions on a cellphone camera.

“He is not in this to draw attention to himself,” Short said at a recent breakfast with journalists sponsored by the Christian Science Monitor. “He is in this to try to help make sure that people get their jobs done. If they are not, they will be held accountable.”

For all of Kelly’s efforts, there is one person at 1600 Pennsylvania Avenue the chief cannot discipline: the president.

At the end of his first negotiation this month with congressional Democratic leaders, Trump turned to Senate Minority Leader Charles E. Schumer (N.Y.) and noted that the press was waiting just outside. Let’s go out right now, the president suggested, and announce the deal, according to one person with knowledge of the meeting.

“I don’t think that’s such a good idea, Mr. President,” Schumer replied, somewhat in jest. “I don’t know what you’re going to say — and I might be forced to contradict you.”

Schumer then gestured at Kelly and added, “I bet he has that same problem.”

The chief of staff, with his boss looking on, simply laughed.

Carol D. Leonnig contributed to this report.