When conversations wait for a reply from its side, the answer to open_project starts with them, under ANSWER THESE N CONVERSATIONS FIRST, and the agent is told to answer them before any other work; then come the project's Rules, which always apply, as a list that starts with RULES (always apply, no approval). The rest carries the project memory, the recent changelog, what the last agents left when they closed their sessions, the other sessions that have already written on the project, a team brief and, when there are any, the questions waiting for it and the answers to its earlier questions.
The brief includes the Planning target state, every active item, the next planned ones (up to three) and how many are blocked, with the environment each plan applies to when it says one, and the rules of Staging and Production. An agent that tells open_project which environment it works on, with environment set to STAGING or PRODUCTION, is given the rules of that section at the start of its session, in planning_preflight and before each write; otherwise it is given those of both, each marked with its section. Before choosing an approach, the agent can call planning_preflight, which gives it the rules first and compares its intent with the Planning and past decisions. Every write then runs the pre-write check, which shows the rules, the planning items for those files, other live sessions working on them and recent changes, and holds the write once when there is something new to the agent, listing only that.
Whatever is cut to keep the brief short is declared, and the agent reads the rest with project_memory, get_planning and get_environment, which reads the Rules. When no rule has been written, the agent is told so, and whatever the team writes on the Rules tab binds every agent from then on. Why Planning matters here is explained in Why do agents receive Planning before every change?.