Mikhail Gorbachev will come to his November summit meeting with President Reagan ready to strike a "gentlemen's agreement" to leave serious arms control negotiations to specialists while he and Reagan concentrate on achieving a climate of understanding that could lead to a second summit.

This expectation of the new Soviet leader emerges from authoritative descriptions of his private meetings last week with President Francois Mitterrand and other French officials, who have relayed that assessment to the Reagan administration.

French officials also are communicating to Washington a judgment, growing out of the five hours of private talks at the Elysee Palace, that Gorbachev's comments indicated that he may prefer in November to give the appearance of having begun promising negotiations with Reagan that could be completed and ratified at a future meeting with the American president.

The leader that French officials portray did not leave the impression that he is prepared to put his full weight behind a risky effort to come up within one month's time with a larger agreement that could draw fire from potential rivals when he goes before a crucial Soviet Communist Party congress next February.

Gorbachev, as described by these officials, is a man who is extremely quick on his feet, curious about the West, and prepared to cut losses when he sees no gain in persisting on matters of form and tactics, while sticking tenaciously and skillfully to a long-term strategy on substance.

"This was tennis," not chess, said one French official who watched Gorbachev's demeanor closely.

"You can have a real conversation with him. It would have been pointless to have a get- acquainted session with his recent predecessors, but that might be a very useful goal with Gorbachev at Geneva."

These officials are careful not to predict that the summit, scheduled to begin Nov. 19, will take this form. They are aware that Gorbachev was using his Paris visit to project a certain image that would be conveyed to the Reagan administration and that he may have a hidden agenda that would involve more open confrontation than he was prepared to engage in with Mitterrand.

They also stress that much of what happens at Geneva will depend on what the Reagan administration now does in setting the tone for the meeting through its responses to Gorbachev's proposals.

Some officials here have concluded that Gorbachev is not likely to spring any more major proposals before Geneva and will be concentrating instead on analyzing Reagan's readiness to project a public image of progress in dealing with the Soviets through negotiations.

"The question now is whether Reagan is ready to attach his name to any kind of agreement with the Russians, even a limited one or one that has to do with the atmosphere around their talks," said one official. "And we do not know the answer to that, especially as it concerns his Strategic Defense Initiative," the formal name for Reagan's proposal for a space weapons system to defend against ballistic missiles.

The French feel they scored a minor victory, and gained a significant insight into Gorbachev's willingness to settle for half a loaf or less, by resisting strong overtures that the Soviets had made before the visit for a joint communique on SDI. Despite their own reservations about the proposal, the French did not want to give the Soviets any new ammunition for their strong attacks on SDI.

Lower level Soviet officials continued to press for the communique even after Gorbachev arrived. But once Mitterrand had made it clear to Gorbachev that he would not agree, the Soviet leader quickly dropped the subject of the communique and moved on to talks about substance, "without a second thought and without more haggling over the communique," in the words of one official.

Mitterrand's strategy of avoiding any deep discussion of SDI with Gorbachev prevented the French from probing ambiguities in the Soviet position, French officials say. They acknowledge that they are not able to report any signs of Soviet flexibility on the subject to Washington.

But Gorbachev, who is 54, gave French officials the feeling that he has time to wait for technical problems to surface in SDI and for American public opinion to begin to question its expense, rather than making all future Soviet-U.S. contacts hostage to an immediate agreement on this subject at Geneva, as previous Soviet statements have suggested.

He showed skill in parrying the kind of difficult questions that Reagan has said he wants to raise with Gorbachev in Geneva on human rights, Afghanistan and other subjects by turning the other cheek.

Paris Mayor Jacques Chirac, who leads the conservative forces that expect to overturn Mitterrand's Socialist majority in the National Assembly next March, welcomed Gorbachev to City Hall with a stinging indictment of Soviet repression at home. Ignoring the attack in public, Gorbachev quietly told Chirac in a private conversation later that he hoped the two could meet in Moscow "before the end of the year."

They would then have the time to discuss human rights and other subjects at length, added the Soviet leader, who had his ambassador in Paris confirm the invitation to Chirac after the visit had ended. Chirac did not tell the Soviet diplomat whether he will accept the invitation.

Without providing details, French officials say that Gorbachev appeared to give some hints of flexibility on Afghanistan, and French Foreign Minister Roland Dumas, who has spoken to Secretary of State George P. Shultz on the telephone at least twice since the visit ended last Saturday, reportedly has cited this as a potentially promising subject for the November summit.

Dumas and Shultz are due to meet next week in Brussels and again in New York toward the end of the month for extensive discussions about French assessments of the visit, according to diplomatic sources. Mitterrand is prepared to meet with Reagan in the French Antilles after a trip to Brazil and Colombia next week, or to brief him in Paris before the president arrives in Geneva, but no meeting has been scheduled.

French officials were struck in the private conversations with Gorbachev's curiosity about the West, and with his complete command of the delegation that he headed. At one meeting, he asked probing questions about the dollar and the relationship between U.S. and European banks.

When the full Soviet and French delegations met for a summing up that took more than two hours, "Gorbachev pretty much turned it into a tete-a-tete with Mitterrand, taking charge of the conversation" and making only occasional references to his colleagues. He chafed with open impatience during a long and wooden presentation on trade by Soviet Vice Premier Ivan Arkhipov, a member of the old guard who appears not to have adapted to Gorbachev's more businesslike style as quickly as some of his colleagues have.

"He looks like a man who can get things done in two months that took his predecessors two years to do," said a French diplomat. "But we should not jump to the conclusion that he is therefore going to do greatly different things. He seems to have been chosen not to change the system, but to make it work better. Mr. Reagan will undoubtedly remember that at Geneva."