The phrase "a ready eye" is correct and usable in written English.
It can be used to describe someone who is observant or alert, often in the context of being prepared to notice details or changes.
Example: "The detective had a ready eye for inconsistencies in the witness's statements."
Alternatives: "an observant eye" or "a vigilant eye".
Precisely six months out from the general election, it might be expected Labour would have been marching in clear, disciplined formation across open ground, guns at the ready, eyes trained on the fixed positions of the enemy.
It's a dream as old as America, and it continues to inspire latter-day Ahabs, harpoons at the ready, eyes peeled for that main chance.
A large herd was on the far side of the river and slightly upstream from where we parked with our cameras ready, eyes glued to our viewfinders.
Although palpably intelligent, with a ready wit and acute eye for absurdity, he took jobs including nailing packing cases, portering and labouring, with forays into the fire service and film projecting.
With a ready grin and twinkling eyes, he rose quickly through union positions, catching the eye of Walter P. Reuther, the union president from the late 1940's until his death in 1970.
Botham, a lumbering giant of a man with a ready smile and twinkling eyes, was proud of founding AAA, Anti-Alcoholics Anonymous.
In walked a stocky guy in jeans and an open-neck shirt, olive-green eyes, a ready smile and a mop of dark hair flecked with gray.
He was blandly handsome, with big, circular eyes, a ready grin, and a shiny mound of dark hair, always parted down the left side.
A small, ageless woman of few words but a ready smile and twinkling eyes, Ms. Rivera acquired Baura from her daughter in Florida.
He symbolises free range against the battery farms of Canary Wharf and other media plantations". Botham, a lumbering giant of a man with a ready smile and twinkling eyes, was proud of founding AAA, Anti-Alcoholics Anonymous.
