A dispatcher command may answer about the build, when place cannot change the answer

The dispatcher's commands have all been about a store: its documents, its tags, its index. deprecations is about the docir running them. It is allowed, on a property the rest of docir doctor does not have, and the property is the rule.

What forced the question¶

A breaking change is announced with a date, by doctor put the dated register in docir doctor, and MCP as a second transport over the dispatcher makes every MCP tool one Request through the dispatcher — one tool per command, never a second implementation. There is no doctor command, so there was no tool, so the reader those dates were written for could not read them (The deprecation register is not askable over MCP).

Adding a tool without a command would have been the quick way and the wrong one: two implementations of one answer is exactly what that rule exists to stop.

The rule: a command may answer about the build when the answer does not depend on where it runs¶

docir doctor — one report for every way docir is subtly wrong kept doctor out of the dispatcher for a good reason — most of what it reports is about the client process: which store the working directory resolved to, whether a stale DOCIR_EMBEDDER is set, whether the daemon on this machine is serving current code. The MCP server runs in the daemon, so those answers would be about the wrong process.

The register is not like that. It is a constant in the installed package plus today's date, and it reads the same in the daemon as in the shell. That is the whole test, and it is narrow on purpose: a command passes it only when running somewhere else cannot change the answer.

Why not fold it into store_status¶

That tool already answers whether this store's index is current, and it gained the store format numbers because those describe a store. Adding the register would have been quicker and would have made one tool about two subjects — a store, and the build reading it — which is the question a reader then has to disentangle every time.

Its own command says which subject it is, and the name says it before the payload does.

What it costs¶

A second place that reads the register — doctor builds its compat section directly, because it must answer while the store is unopenable, and a dispatcher command cannot. They are not two implementations: both call describe_deprecations, which shapes the payload once. The split is between transports, not between answers.

Dispatcher also gains a clock, which it had no reason for before. That is honest rather than incidental: "has this date passed" is a question about today, and every other clock in docir is injected so a test can stand on the far side of a sunset without waiting for it.

What it does not become¶

A place for the rest of doctor. The environment half stays out, and the test is unchanged: if running in the daemon rather than the shell can change the answer, it is not a command.