Hosted OpenAI-compatible APIs often serve chat but not GET /models
(Volcengine Ark Agent Plan returns 404), so connect failed. Accept a
typed list of model IDs: merged into discovered models when /models
works, used alone when it does not. The typed list is stored as
customProvider.manualModels so reconnects and pin saves keep it.
A local endpoint that publishes no limits — LM Studio's /models says nothing —
left every model on the 8192/4096 defaults with no way to say "this one has a
131k window". Each discovered model now gets three optional pins in the
endpoint editor: context window, max output tokens, thinking (auto/on/off).
A pin always wins: user pin → what the endpoint published → compiled default.
Blank means no opinion, so discovery keeps ruling wherever you don't pin. Pins
live in customProvider.overrides keyed by model id, stored apart from the
discovery snapshot: a reconnect refreshes the models and prunes the pins of
models that vanished while keeping the rest.
Pins are written by PATCH /api/custom-provider, which never probes — the whole
point is configuring a server that isn't answering /models correctly. Connect
still probes and still fails loudly when the endpoint is down. A pin under 2048
tokens is rejected on the write side and clamped up on the read path, matching
the compaction-floor discipline.
Connecting was one-way: POST could only replace the base URL, and the only
escape was hand-editing settings.json. DELETE now mirrors POST — drop the
stored section, delete the reserved key, unregister the provider from
piModels() — and the connect editor grows a Disconnect beside Connect,
following the stored-key rows' Delete pattern (quiet text, one click, no
confirm, only once there is an endpoint to remove).
Review pass: shorten verbose doc comments across the custom-endpoint code,
merge duplicate imports, share one synthetic provider entry between the keys
section and setup dialog, collapse the duplicated connect-editor block, revert
an unrelated settings-route drive-by.
iamabhishekt