In an early chapter of John Steinbeck’s 1939 novel The Grapes of Wrath, the Oklahoma farmers encounter the technology that will help drive them off the land: the tractor. “One man on a tractor can take the place of 12 or 14 families. Pay him a wage and take all the crop,” an agent for the land owner says.

Another of those moments came this week, this time a warning for hundreds of thousands of white-collar workers. Anthropic, the American AI company that labours largely in the shadow of the better-known OpenAI, unveiled the latest set of tools for its office assistant, Cowork.

There are 11, which will tackle a range of tasks from simple stuff like keeping calendars up to date, to more complicated jobs like chasing sales leads and reviewing contracts. It is a paid-for service; Cowork costs from £18 a month and up to ten times that depending on how much you use it and what level of access you want. There is a degree of flexibility: one of the plug-ins is designed to be customisable, so you can set it up to do a job that particularly irks you.

Not to be outdone, OpenAI responded on Thursday with Frontier, a new service that lets you build your own “agent” as these task-specific AI tools are called.

On the face of it, this didn’t seem to be a giant leap forward. There are dozens of AI office assistants out there already. The market thought it a tipping point, however, and focused on a group of specialist-information providers believed to be most at risk. Shares in FTSE 100 stalwart Relx, the information provider formerly known as Reed Elsevier, dropped 13 per cent on Tuesday, while its Dutch rival, Wolters Kluwer, was down 9 per cent. London Stock Exchange Group, whose information arm is much larger than its markets business, fell 9 per cent, and there were smaller declines for others in similar areas — Pearson and Experian on the London market, and Thomson Reuters, Morningstar, LegalZoom and Factset in the US.

As my colleague Alistair Osborne pointed out on Thursday, some of these falls don’t make much sense. Relx, for example, is judged to be exposed because one of its big earners is LexisNexis, the vast database of case law, judgments and company filings that make it invaluable to law firms. Relx already has its own in-house AI services, and has struck a LexisNexis licensing deal with Harvey, a San Francisco-based legal AI service that is backed by OpenAI, and a gaggle of venture capital investors.

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But that’s as far as it goes. LexisNexis, the valuable legal bit of Relx, is not licensed to one of the large general AIs, and won’t suddenly pop up as the power behind one of the new Cowork plug-ins. The argument that this irreplaceable repository of legal knowledge is suddenly going to lose its value doesn’t stack up — unless at some point Relx is dumb enough to lose control of its distribution.

That could still happen — lots of other possessors of vital trade information have lost out to online competitors in the past two decades — but the launch of one more legal AI doesn’t mean the disruptors have suddenly taken over. (Harvey, by the way, is thanks in part to the LexisNexis tie-up, much more expensive than Cowork. There is no public price list, but the base price is reported to be $1,200 per user per month).

The real loss of value is likely to be felt by individual workers, not knowledge providers. To stretch the Grapes of Wrath analogy, the advent of the tractor didn’t mean the land, seed or fertiliser lost their value. The people who used them, however, did. The Cowork legal plug-in is a good example. One activity from which junior lawyers generate billable hours is reviewing contracts — making sure they make sense, and that they follow the in-house rules of the signatory company. Cowork automates this. You put in your internal rules, give it a few other guidelines, and it will go through a contract and put green/amber/red tags on each clause.

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If you are a law firm or in-house legal team that has to review regular minor contract changes, perhaps with hundreds of suppliers, this could be an absolute godsend. You might want a few flesh-and-blood lawyers around to look at the red and amber flags, but after a while Cowork is likely to get good at eliminating the false alerts. It is probably already pretty good; a 2018 study by LawGeex, another of the legal AI services, asked 20 top-quality lawyers to check the validity of a non-disclosure agreement. It took them on average 92 minutes, with an 85 per cent accuracy rate. The AI took 26 seconds, with 94 per cent accuracy.

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Strangely, there doesn’t seem to be much hard evidence that the legal jobs market is suffering. Newly qualified lawyers are still commanding big salaries, particularly in London, and while there are some anecdotal reports the number of jobs advertised is falling, there does not seem to be any sharp contraction — and certainly not the kind of big change suggested by the share price moves this week.

Markets, of course, are all about trying to price the future, and what happened to Relx and co this week is an attempt by investors to do something — anything — in reaction to all the AI news. That also explains what happened at Microsoft, which fell 10 per cent this week. Its CoPilot AI assistant (about £20 a month) could lose out to these new agent services.

There was also a broader tech sell-off, with Palantir, Amazon, Alphabet and Oracle all having bad weeks, reflecting long-standing fears whether the billions being spent will ever yield a profit. Picking the corporate winners and losers in AI is tricky, but it is not too hard to work out where the greatest pain will be felt. In the Grapes of Wrath the tractor doesn’t just take the farmers’ jobs, but it smashes straight through their houses. The new AI agents unleashed this week have the potential to cut a similar swathe through white-collar professions.