Diplomacy

In Planets.nu, there are several types of diplomatic arrangements you can have with other players. You can set diplomatic status with other players from the Diplomacy screen on the dashboard.

Diplomatic Settings

Diplomatic settings can be set by both players (e.g. sharing intel with each other) or by just by one player.

Send Ambassador

Sending an ambassador to another player simply allows you to receive messages from another player instantly, instead of having to wait for the next turn before reading their messages.
In Campaign mode, a Birdman player with Diplomatic Spies enabled can see your diplomatic status with all other players if you send an ambassador to them.

Safe Passage

If you give Safe Passage to a player, the other player can travel through your minefields or web minefields without hitting any mines or being drained of fuel. Safe Passage will prevent your ships from attacking another player, even if you have Primary Enemy set, or the Kill mission set. Giving safe passage to another player will also prevent them from sweeping your minefields.
If you give Safe Passage to someone, they will be shown all your minefields. They will also receive minefield data about other players (with some conditions--see Notes section below).

Share Intel

Share intel includes the Safe Passage agreement. If you share intel with another player, you share information you have about ship locations and planet ownership. If you share intel with a player, you will share:

• The location of all your planets and ships. Specific details are not shared about your planets or your ships. Starbase locations are not shared.
• Your VCR combats.
• Detailed information about any un-owned planets or planets that become un-owned.
• The location and detailed information of planets, ships and starbases belonging to other players that you know about. This includes both intel you discover yourself and information shared by other players.
  

Important Exception: You will not pass on any information whatsoever about planets or ships belonging to players currently sharing intel with you. It does not matter how your obtained this information.

Full Alliance

Full alliance includes Safe Passage and Share Intel. You will share additional intel with the other player, including all details about your ships (e.g. weapons, ammunition, fuel, damage), except for their friendly codes.

When you have a full alliance with other players, you can combine your scores in order to win the game. For example, in a typical 500-planet game with the Diplomatic Planets win condition enabled, a single player can win by controlling 200 planets; but with a Full Alliance, two (or more) players can win the game when they control 250 planets together.

When both players set their diplomatic status to Full Alliance, the formation of their alliance is publicly announced in the game's newsfeed. It is the only diplomatic status that is publicly announced. If an alliance breaks up it is also announced publicly. Because of the public announcement of alliances, most players wait until near the end of the game before declaring an alliance with each other. In team games, players on the same team start the game with Full Alliance enabled and it cannot be turned off.

Notes & Limitations of Diplomatic Agreements

Actions not prevented by Safe Passage

• Ground combat (including Imperial Assault) is not prevented by safe passage.
• Pillage and Rebel Ground Attack missions are not prevented by safe passage.

Information shared via other players

• Once a player stops sharing intel with you, you will pass on any previously learned information from them to others you are sharing intel with (i.e. info about their planets, starbases, minefields and ship data). Intel Sharing will share info about any player you do not currently receive intel from.
• If someone gives safe passage to you, you will receive their minefield data, which you will in turn share with other players. The exception to this rule is when you give safe passage to that player in return. If you do, you will not share their minefield data with others.

Information never shared

Some of your information is never shared via diplomatic agreements. The official list can be found here.

• Planet build goals and happiness info.
• Your ships' primary enemy, mission and mission target.
• Starbase parts inventory and primary orders.
• Movement history of your ship (info shown by clicking "history" on the left pane).
• Any future planned orders for your ally's upcoming turn. (I.e. you cannot see what your ally is planning--only what they've already done last turn).
• As of 2017/12, wormhole scans are never shared. (This might change in the future since wormholes are a new feature.)

Bugs

According to Big Beefer in Jan. 2024, There is a minor bug where you will not receive info on your allies' minefields unless you have at least one ship using the minesweep mission. It doesn't really matter what ship it is, it can be a freighter far from the action and you will still get info on all of your allies' fields.