Contract Law - Part 1: Formation and Performance

Common Law versus UCC Article 2

The common law, built from court decisions, governs contracts for services, real estate, and employment, while Article 2 of the Uniform Commercial Code governs sales of goods, meaning tangible, movable things. When one contract mixes goods and services, courts generally ask which one predominates. Deciding which body governs is the first step in every contract analysis, because the UCC is looser than the common law about formation and stricter about performance.

Offer and Acceptance

Offer and acceptance are how two parties reach mutual assent. An offer is a definite proposal made with the intent to be bound, as a reasonable person would read it, and an acceptance agrees to its terms without qualification. Under the common law’s mirror image rule, a reply that changes a term is a counteroffer, while the UCC can let a contract for goods form even when the acceptance changes terms.

Consideration

Consideration is what each side gives up in a bargained-for exchange: money, a service, or a promise not to do something it has a right to do. A promise to make a gift is generally unenforceable, because nothing comes back to the giver in exchange for it. Courts rarely ask whether the exchange was a good deal, only whether there was one.

Substantial Performance

Under the common law, a party that delivers the contract’s main purpose, departing from it only in minor ways and in good faith, has substantially performed. It can recover the contract price, less the other side’s damages for the shortfall, so a small deviation cannot wipe out a large obligation. A builder who follows the plans but installs a comparable brand of pipe is the classic example.

The Perfect Tender Rule

Under the UCC, a buyer may reject a delivery of goods that fails the contract in any respect: the wrong color, the wrong quantity, or a day late. The seller’s right to cure softens that strictness by letting the seller fix a defective delivery, generally within the time the contract allows. Which rule applies, this one or substantial performance, turns on the first question in every analysis: goods or services.

Assignment and Third-Party Beneficiaries

A party can usually assign its rights under a contract to someone else and delegate its duties, though a party that delegates stays liable if the substitute does not perform. A contract made for the benefit of an outsider can give that intended beneficiary the right to enforce it. These rules decide who can sue and who can be sued once a contract changes hands, and business contracts change hands all the time.

Part 1: Analyze the Fact Patterns

Read the four fact patterns below and take them one at a time. Open with the Concept Primer, which names the contract concepts in play and whether the common law or UCC Article 2 governs. Then use the Issue Spotter to state the exact legal question in one sentence. Last, open the case linked under the fact pattern on Google Scholar and paste its text into the Case Analyst, so the AI works from the opinion rather than its memory of it. The fact patterns are hypotheticals, so the opinion gives you the rule; applying it to these facts is your job.

Fact Pattern 1: During a televised interview, John Doe offered a reward of $1,000,000 to anyone who could retrieve his wedding ring from the shark that bit off his hand. The interviewer asked if he was joking, but John asserted he was serious. Jane Smith went fishing, caught the shark, found the ring, and demanded the reward. John refused to pay, claiming it was a joke. Jane filed a lawsuit for breach of contract. During discovery, unedited footage showed John laughing and admitting he was joking. Kolodziej v. Mason, 774 F.3d 736 (11th Cir. 2014) (opens in a new tab).

Fact Pattern 2: Jack carefully drafts an online advertisement: “For Sale: 1967 Ford Mustang, excellent condition, $6500.” He made a typographical error and meant to set the price at $65,000. Jill spots the ad, gathers $6,500 in cash, and heads to Jack’s address. She presents the cash and asks for the keys. Jack refuses to sell, explaining the typo. Jill insists the advertisement was an offer she accepted and sues for breach of contract. Jackson v. Inv. Corp. of Palm Beach, 585 So. 2d 949 (Fla. 4th DCA 1991) (opens in a new tab).

Fact Pattern 3: Mr. Taylor wanted a greenhouse built and approached Build-It-Right Construction. The company sent a detailed proposal specifying pressure-treated lumber. Mr. Taylor signed to indicate acceptance but wrote in a request to use cypress wood instead. Build-It-Right never responded or commenced work. Mr. Taylor sued for breach of contract. Pena v. Fox, 198 So. 3d 61 (Fla. 2d DCA 2015) (opens in a new tab).

Fact Pattern 4: Acme Construction entered a $50,000 contract to remodel Harry’s kitchen, specifying an imported Italian marble backsplash. Due to a global shortage, Acme substituted a nearly identical, high-quality domestic marble that cost Acme $500 less than the Italian version. Harry loved the kitchen but refused to pay the remaining $10,000 of the contract price upon learning about the substitution, arguing Acme failed to fully perform. Ocean Ridge Dev. Corp. v. Quality Plastering, Inc., 247 So. 2d 72 (Fla. 4th DCA 1971) (opens in a new tab).

Part 2: Draft Your Responses

Write a clear, step-by-step explanation of at least 100 words for each fact pattern, stating how the dispute should be resolved and why. Name the body of law that governs and the rules that apply, then show how the facts meet them; a bare verdict is not an explanation. Paste each draft into the Draft Challenger, then revise it in your own words. Post all four responses together as a single discussion post.

Part 3: Share Chat Link

Include one AI chat link with a 1–2 sentence explanation of what the conversation shows and why you chose to share it.

Concept Primer

Sequencing: asking for the concepts and the governing law before any verdict keeps the model from picking a winner first and reasoning backward to justify it. A lawyer works in the same order.

Issue Spotter

Forced precision: a one-sentence issue is the first step of IRAC in miniature. A vague issue breeds a vague analysis, and one sentence leaves vagueness nowhere to hide.

Case Analyst

Source grounding, the responsible-use step: models misremember holdings, so the prompt confines the AI to the opinion you paste. A rule you can trace to a paragraph of the real case is the only kind worth citing.

Draft Challenger

Red-teaming: models lean toward agreeing with you, and an order to attack works against that lean. The ban on rewriting keeps the stronger draft in your own words.