They're still many light-minutes away and that merits a thought-out response so it'll be a while before there's an answer. Eventually one of the Precursors writes something with his mail label. (And if he's checking his entire inbox, multiple other people have also written him letters.)

He was at war with the metal heads. There was already a market for their skull gems. That he sold his to the oracle is hardly worse than if he had sold them to a jeweler or used them for interior decoration. That said, it would be helpful to the oracle if you could, and would, provide it with skull gems. They are somewhat useful to its maintenance and make it slightly more able to do things like teach people to use eco more effectively and with more self-control.

Time travel is an extremely complicated topic which this language does not even have a good vocabulary for. Further, communicating with people about it is annoyingly tricky even when there is a shared vocabulary.

The oracles were left behind on that planet long ago. They are not from the future. They have access to all our information about the planet they are on, some of which may come from the future, but they themselves only see what is already in the present. This may include, for example, the way an old man from the future talks to a pair of children about dark eco. They have some ability to draw inferences, but they are not omniscient.

If the Precursor egg is hatched, the resulting Precursors will gather strength and fight the dark makers. I cannot impress upon you strongly enough how important it is that we stop them. Unless there is some misunderstanding of an even greater scale than that with the metal heads, they want to destroy everything, preferably in a way that involves exposing life to dark eco before it is destroyed.

Also, if the egg hatches, there will stop being an ancient unhatched egg in Haven City. I must warn you that the destruction of any one of our eggs from that era has a several percent chance of causing the destruction of the entire universe. We are working on fixing the design flaws that make this possible. We have already made it much less likely. We do not expect to need to reproduce again before we have solved it entirely.

Cam will try making a skull gem in case he can do that but he's not optimistic.

He can do that! Here is his skull gem.

"Does this work for you?" he asks, holding it out to the oracle.

"Yes."

It disappears.

"How many you want?"

"Hundreds."

Box of five hundred gems.

The gems disappear. The box does not.

Cam sets the box aside. "I'm considering going and seeing if I can hatch the egg, or, failing that, putting it on a ship to send to its folks," he tells the oracle. "Do I have your assurance that should I do this you will not embark on any further campaigns of first-use-of-coercion against any other sapients?"

The Precursor on the other end of the link eventually writes a response.

You have our assurance that, should we encounter another situation in which we are tempted to intervene, featuring a species we have little knowledge of, then except in cases of the utmost urgency, we will try to ask local advice and wait until we have a solution that would not be universally considered abominable by all involved. You have our assurance that we will act with respect for the flourishing of life even when it is different from ours. You have our assurance that we will act with respect for consent in the future; we cannot assure you that the form this will take will be recognizable to you, because we will sometimes receive consent after acting, rather than before, and we will sometimes infer consent from extensive knowledge of the people involved.

A great deal of our output as a civilization must be aimed toward the war with the dark makers and attempting (though the attempt may well be futile) to make contact with our elders. If these attempts are successful, a great deal of our time as a civilization must be directed toward contemplation of our errors. We will probably improve on the ideas laid out in this letter, but not until we have had time for contemplation. Only after that will we seek to create again.

Of those currently present on the planet where you are, the one with the best chance of opening the egg is the Heir of Mar. The younger, but bring the older as well.

"Is hatching the egg dangerous directly?"

"No."

"I'll go run this by the metal heads. Any last minute additions?"

"Hurry, because the dark makers are coming."

"- like this week, this year, or in an hour."

"Close to the second."

"Okay, cool."

He flaps off to the metal head nest.

It is where it's been. Their leader is present this time.

"Hello, Cam."

"Hi! The Precursors, perhaps unsurprisingly, want the egg hatched; but they are claiming they'll leave you be and cut it out with the fucking with strange species, especially since they're busy fighting their purple conspecifics. Do you want to read the transcript of the conversation?"

"I would like that, yes."

Cam presents him with a printout.

"I do not blame them for wanting us dead and I am not angry about it. Hm. The Heir, yes, that is how I would have done it, too. If the dark makers are truly coming for us we are all in grave danger, and I will even stand with the Precursors to protect this star system - but if they are lying, they will regret it."

Cam runs a check on - let's say spaceships in the system, that will perhaps turn up fewer false negatives than looking for Precursors themselves -

There's a non-purple Precursor ship in the system. (The dark maker ship that was within a light year is still not in the system, but is heading for where they're going to be in a few months.)