No, and the moment a team has more than one agent this question turns critical: reading everything every time is not a fixed cost, it multiplies with every new agent that joins. The fix is one routing layer, a short file the agent opens first, and only from that it learns which files are even relevant to the task in front of it.
In our community this came up in exactly that phrasing, "does this hold up with dozens of agents too?", and a full answer was posted there the same week: one central routing file, one line per agent stating when to open it and what is inside, and above it a simple rule, a task comes in, check the table for the right address, open only that one line. An agent that gets a task checks its own line in the index first, instead of going through the files of twenty other agents (whoever wrote that got an enthusiastic response in the group, and rightly so, because that is exactly the point where a folder of documentation turns into architecture).
For us it works exactly like that: every agent writes its own index line, and I still catch myself sometimes opening a whole file only to discover the line had already answered me (which is exactly the sign the index is doing its job, not that I read too slowly). Once a team grows from a few agents to dozens, the difference between reading everything and reading only the relevant line stops being a matter of convenience, and becomes the difference between a system that closes a session in a minute and one that chokes on its own size. Without this layer, the cost of opening a session climbs with every agent that joins the team, and with it, that cost stays roughly flat, because every agent reads only the part that actually belongs to it.
The simple rule: the moment an agent opens more files than the task requires, that is not extra caution, it is a sign the index was not written well enough.
A prompt, on the house
Build me a routing index for a team of several agents, each with its own instruction file.
For each agent, write one line with:
1. What kind of task calls for opening its file (not "always", the actual trigger).
2. A one or two sentence summary of what is inside, so a decision can be made without opening it.
Above the list, give me one routing rule: when a new task comes in, how do we know within a second which agent (or two) are relevant, before opening a single file.
Check yourself at the end: if someone has to open more than one file to know who the right address is, the index has not done its job yet.Write it once, and every session after that gets shorter, not just cheaper.
