Why it is shaped this way

Names

A name, a structural witness, and the right to extend the recording are three jobs, not one identity.

A name, a structural witness, and the right to extend the recording are three jobs. They are not one identity.

Why#

It is tempting to stuff lineage, the whole structural map, a node index, and who currently holds the pen into a single value that "handles identity." Every handle then carries a chain it does not read. Every training step pays for a path nobody walks. Equality starts meaning too many things: same node, same family, same prefix, same writer.

The fat name also fights the one property a node handle must have. Names are copied constantly — into detached sets, into entries, across threads, across notebook cells. They have to stay cheap. A witness of graph structure does not.

The idea#

w.index()          = 0
doubled.index()    = 2
parameters.of(w)   = 0.25
run.of(doubled)    = 0.5
network.node(w)    = 0  Parameter                         []

Plate 1. A Value records; a Symbol is the detached name every later phase reads through. The proxy dies at the seal, the name does not.

Three jobs:

A name answers "this node." It is detached, copyable, and thin: a family token plus a position. Nodes never move, so the position is stable for the life of that family. Equality of names is equality of node identity, nothing else.
A structural witness answers "same family, and the same map of nodes, over this length?" Fields, plans, and runs ask this when they meet a name or another table. It is a read-only agreement over a prefix, not a name, and not whole-chain equality. Prefix agreement is the check; Eq is the wrong algebra.
Writer rights answer "who may append?" That is mutation of the recording phase, not a property of a node. Once spec and state are split, the question almost stops being askable: there is one live recording or one sealed spec per family, by ownership, and training never appends. The right to extend is possessing the recording phase, not holding a richer id.

Construction handles are a fourth, narrower thing: a name plus a borrow of the recording phase, so a proxy cannot outlive the seal. They are the spelling of expressions. They are not the currency of anything after.

Consequences#

Names stay copyable and payload-free. They do not grow a chain, a generation, or a lock.
A name from another family, or past the length a table covers, fails loudly. That is kinship as a check, not as a type the caller has to hold.
Plans and runs do not borrow the spec. They carry enough to reject a foreign name and to serve their prefix after the spec reopens.
Linear extension never moves a node, so a name taken before a reopen still names that node afterwards.
Mixing two live recordings in one expression is a recording error. Lifetimes do not brand topologies; the check stays at the expression.

Not this#

Merging family, chain, and index into one identity that also handles forking. Wrong granularity; fights cheap names; puts the writer protocol on the thing that means "node."
Putting the structural map on every name.
Treating name equality as "same graph prefix" or "same writer."
A post-seal proxy. After the freeze, everything speaks names. The sealed spec has no proxy type; that absence is the design.

See Spec and state for why writer rights leave the public surface, and Vision for the tape as spec.

Spelled today#

Symbol is origin plus index, Copy. Value borrows the Tape and dies at into_network. Origin is crate-private; dependents see "belongs to a different network" and coverage panics. Detach is how names leave construction. This section may rot; the rest must not.