Update docs/source-2.0/additional-specs/ai-traits.rst

Co-authored-by: Kevin Stich <kevin@kstich.com>

Author: yasmewad

docs/source-2.0/additional-specs/ai-traits.rst

@@ -10,9 +10,9 @@ Smithy AI traits provide metadata for service authors to embed contextual inform
 .. smithy-trait:: smithy.ai#prompts
 .. _smithy.ai#prompts-trait:
 
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 ``smithy.ai#prompts`` trait
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+---------------------------
 
 Summary
     Defines prompt templates that provide contextual guidance to LLMs for understanding when and how to use operations or services. This trait can be used to generate prompts for a Model Context Protocol (MCP) server.