Full Idea
In intentional explanations of behaviour patterns in the behaviour are explained by the fact that the agent has a representation of that very pattern in its intentional apparatus, which functions causally in the production of the behaviour.
Gist of Idea
We explain behaviour in terms of actual internal representations in the agent
Source
John Searle (The Rediscovery of the Mind [1992], Ch.10.IV)
Book Reference
Searle,John R.: 'The Rediscovery of the Mind' [MIT 1999], p.240
A Reaction
Problem cases would be where someone's behaviour doesn't come out quite as planned (e.g. the sentence spoken failed to match the proposition intended), and panic behaviour.