The seam answered one question — what is behind this environment-variable
name — and that shape cannot hold what an authorization grant is: a
multi-field, rotating value keyed by a provider id rather than by a POSIX
identifier. The Models page already works around the gap by inventing a
synthetic environment name (`MINIMAX_CN_API_KEY`) for a route the user added
by hand, because the store's key must look like one.
`CredentialKey` is `<scope>/<id>`, where the scope is the owning plugin's
registered name. The owner is in the key because a `grant` payload is written
in its owner's format: two plugins serving the same provider name would
otherwise read each other's payload, and a record left by an uninstalled
plugin could not be told from a live one. The `/` also keeps the grammar
disjoint from `CredentialRef`, so the key spaces cannot collide.
`CredentialRecord` is `api-key` (key and/or provider environment values) or
`grant` (an opaque, owner-owned payload). The asymmetry is deliberate: an api
key is the harness's own data, a grant is a package it carries for someone
else. `modifyRecord` is the only write path because a correct write depends
on the current value — a token refresh is read-decide-replace under one
cross-process lock, without which two processes rotating one refresh token
lose whichever wrote first.
`.credentials.yaml` becomes a versioned two-section document. The pre-release
flat layout is refused by name, with the entry count and the one edit needed,
rather than read as an empty store — which would surface as an authentication
failure on the first request instead of at load. A grant payload is admitted
in both directions, so a value the document could not read back exactly as
written is refused rather than stored lossily.
86a9f8c862