The Dagda is as the Dagda Does.
The Dagda is known as the 'Good God' not because he is morally good, but more that he is good at everything.
We see this in the Irish Lore during the Second Battle of Moytura. Nuada abdicates the kingship in favour of Lugh. He then gathers a variety of forces of the Tuatha Dé Danann to talk war offerings. What follows is an extract from that that text translated by Whitley Stokes:
There after the wizards of Ireland were summoned to them, and their leeches and charioteers and smiths and farmers and brehons. They held speech with them in secret.
Then Nuada inquired of the sorcerer whose name was Mathgen, what power he could wield? He answered that through his contrivance he would cast the mountains of Ireland on the Fomorians, and roll their summits against the ground. And he declared to them that the twelve chief mountains of the land of Erin would support the Tuatha Dé Danonn, in battling for them, to wit, Slieve League, and Denna Ulad and the Mourne Mountains, and Bri Ruri and Slieve Bloom and Sliab Snechtai, Slemish and Blai-sliab and Nemthenn and Sliab Maccu Belgodon and Segais and Cruachan Aigle.
Then he asks of the cupbearer, what power he could wield? He answered that he would bring the twelve chief loughs of Ireland before the Fomorians, and that they would not find water therein, whatever thirst might seize them. These are those loughs: Derg-loch, Loch Luimnigh, Lough Corrib, Lough Ree, Lough Mask, Strangford Lough, Loch Laeig, Lough Neagh, Lough Foyle, Lough Gara, Lough Reagh, Márloch.6 They would betake themselves to the twelve chief rivers of Ireland, even Bush, Boyne, Baa, Nem, Lee, Shannon, Moy, Sligo, Erne, Finn, Liffey, Suir; and they will all be hidden from the Fomorians, so that they will not find a drop therein. Drink shall be provided for the men of Ireland, though they bide in the battle to the end of seven years.
Then said Figol son of Mamos, their druid: ‘I will cause three showers of fire to pour on the faces of the Fomorian host, and I will take out of them two thirds of their valour and their bravery and their strength, and I will bind their urine in their own bodies and in the bodies of their horses. Every breath that the men of Ireland shall exhale will be an increase of valour and bravery and strength to them. Though they bide in the battle till the end of seven years they will not be weary in any wise.’
Then Nuada inquired of the sorcerer whose name was Mathgen, what power he could wield? He answered that through his contrivance he would cast the mountains of Ireland on the Fomorians, and roll their summits against the ground. And he declared to them that the twelve chief mountains of the land of Erin would support the Tuatha Dé Danonn, in battling for them, to wit, Slieve League, and Denna Ulad and the Mourne Mountains, and Bri Ruri and Slieve Bloom and Sliab Snechtai, Slemish and Blai-sliab and Nemthenn and Sliab Maccu Belgodon and Segais and Cruachan Aigle.
Then he asks of the cupbearer, what power he could wield? He answered that he would bring the twelve chief loughs of Ireland before the Fomorians, and that they would not find water therein, whatever thirst might seize them. These are those loughs: Derg-loch, Loch Luimnigh, Lough Corrib, Lough Ree, Lough Mask, Strangford Lough, Loch Laeig, Lough Neagh, Lough Foyle, Lough Gara, Lough Reagh, Márloch.6 They would betake themselves to the twelve chief rivers of Ireland, even Bush, Boyne, Baa, Nem, Lee, Shannon, Moy, Sligo, Erne, Finn, Liffey, Suir; and they will all be hidden from the Fomorians, so that they will not find a drop therein. Drink shall be provided for the men of Ireland, though they bide in the battle to the end of seven years.
Then said Figol son of Mamos, their druid: ‘I will cause three showers of fire to pour on the faces of the Fomorian host, and I will take out of them two thirds of their valour and their bravery and their strength, and I will bind their urine in their own bodies and in the bodies of their horses. Every breath that the men of Ireland shall exhale will be an increase of valour and bravery and strength to them. Though they bide in the battle till the end of seven years they will not be weary in any wise.’
Said the Dagda: ‘The power which ye boast I shall wield it all by myself.’ ‘It is thou art the Dagda (good hand)’ saith everyone: wherefore thenceforward the name ‘Dagda’ adhered to him.
When battle was joined the Dagda delivered on all that he promised. The offered labours show authority over near all the elemental powers, the earth of the mountains, the water of the rivers, the air of the breath, and the fires from the sky. All of this power the Dagda brings to bear, so that his Tuath may survive the invasion of the Fomorian war hosts.
So you could say the Dagda is as the Dagda Does.