You should work to understand all the noise and data that is being directed at the team and turn into something useful for individual team members. If you merely pass information through then you will be overloading or confusing people, because often extracting the signal from the noise is a full time job (your job!). You can't expect someone to do this effectively as well as their own role.
The information you should share is strategic direction, priorities, and background information about things that might affect the team. Then you connect your team members to the people they need access to do their jobs; if you're trying to act as a go-between you're just adding latency and noise to the process.
In your example your team member needs to know how important the project relative to their other work, what your expectations are around timing or effort, and then to be connected to a stakeholder who can fill them in on the details.
The information you should share is strategic direction, priorities, and background information about things that might affect the team. Then you connect your team members to the people they need access to do their jobs; if you're trying to act as a go-between you're just adding latency and noise to the process.
In your example your team member needs to know how important the project relative to their other work, what your expectations are around timing or effort, and then to be connected to a stakeholder who can fill them in on the details.