Claude Task Contract: The 6-Part Prompt Specification

PromptLayer's production guide observes that the best Claude prompts look like engineering specs rather than clever prose, starting with a 6-part Task Contract covering Input, Output, Rules, Context, Failure behavior, and Evaluation criteria.

<task_contract> <input>Customer support thread JSON and account tier metadata.</input> <output>Write a 3-bullet internal support summary. Include the customer's goal, the blocker, and the next action.</output> <rules>Act like a senior engineer. Do not include greetings, apologies, or speculation.</rules> <context>Use only the attached <ticket_log> and <sla_policy> tags.</context> <failure_behavior>When information is missing, unsafe, or ambiguous, output "INSUFFICIENT_EVIDENCE: [missing field]" and abstain from guessing.</failure_behavior> </task_contract>