MACBETH is a constraint-based tactical planning engine for multi-agent teams. MACBETH is designed for domains in which a human user must quickly specify a mission to a team of autonomous agents. In these domains, "puzzle-mode" thinking to come up with novel plans is not important; the key task is to rapidly and accurately tailor existing plans to novel situations. To this end, MACBETH combines hierarchical task network planning with modern constraint reasoning techniques, into a mixed-initiative planning system. This mixed-initiative planning system is driven by a graphical user interface inspired by a "playbook" metaphor, to generate, check and modify plans for teams of heterogeneous agents. MACBETH has been tested in two robotics domains: Unmanned Combat Aerial Vehicles (UCAV) sorties and Tactical Mobile Robotics (TMR).