Legal Position on Sale-Purchase Agreements
Although I am not a practicing lawyer, I feel that the legal position would be somewhat like this: If you have ever witnessed a sale-purchase transaction of a property, like the example you have quoted, you may know that simultaneously the parties also enter into an 'Agreement to Sell,' and the purchaser also makes a part payment (consideration) of the agreed amount to the seller. In such agreements, the total consideration price (total cost) is written, which the purchaser would pay to the seller. Usually, it is also agreed between the parties that the seller will sell to the purchaser for the agreed amount, but if he fails to do so, he will return double the amount (consideration) that has been advanced to him. Also, if the purchaser fails to pay the balance amount within the stipulated time, his partial payment made would be forfeited by the seller.
Situations Under Sale-Purchase Agreement
1. If the seller revokes the agreement or fails to appear before the Registrar for the transfer of property when the purchaser marks his presence there along with the balance amount, the seller would be liable to pay double the amount he has already received from the purchaser. If the seller fails to pay back, the purchaser will file a suit for recovery as per the terms of the agreement. He will claim this amount under the Indian Contract Act, 1872.
2. If the seller marks his presence before the Registrar for the transfer of property but the purchaser does not appear, or if the purchaser revokes the agreement, the seller will keep the money advanced to him by the purchaser, and the purchaser cannot claim it as per the terms of the agreement.
3. If the seller, after receiving the full amount of money (consideration), does not appear before the Registrar for the transfer of property, the purchaser can file a suit for specific performance under the Specific Relief Act, 1963, and force him to transfer the property to him.
Hence, in these kinds of agreements, the part-payment or full payment is the 'consideration.' As per law, consideration could even be paltry sums, say one penny or one rupee. Such agreements can be legally forced to be performed specifically by the erring party through the court of law in India, i.e., under the provisions of the Specific Relief Act, 1963.
Contracts of Service vs. Sale-Purchase Agreements
However, this is not the situation in cases of contracts of service, i.e., contracts between employer and employee. These kinds of agreements cannot be enforced through courts in view of Section 14(1)(b) of the Specific Relief Act, 1963, according to which a contract, the performance of which involves continuous duty that the court cannot supervise, cannot be enforced. If the employer still forces an employee to work, it will amount to 'bonded labour' under the Bonded Labour System (Abolition) Act, 1976.
Therefore, it seems that an employment contract is a form of contract for personal service, which the courts recognize as expressing the social relationship of employer and employee, as opposed to other relationships, i.e., commercial or any other kind.
Offer Letter vs. Employment Agreement
In the case at hand, it can be presumed that it is simply an 'Offer Letter' as the terms and conditions of service have not been specified. It cannot be termed as an 'Employment Agreement.' It is also presumed that the employer has not yet disclosed all the 'terms and conditions of employment' to the employee in this 'Offer Letter,' as the person who seeks this clarification has not provided any such description.
Hope I have been able to clarify my viewpoint.
Best wishes and regards.