docs(custom-model): align the docs and comments with the core behaviour

src/config/cli-registry/types.ts

@@ -812,9 +812,11 @@ export interface CliCapabilities {
    * for pi and omp (`--model custom/<id>`, or the CLI stays on its own default
    * provider and reports "No API key found for the selected model") or for
    * grok (`--model codeman-custom`, the `[model.<name>]` block the config
-   * declares). Absent = the config alone selects the model (claude's env vars,
-   * opencode's blob, codex's top-level `model` key). Applied by the session's
-   * respawn options through the entry's `legacyConfigField`, never by id.
+   * declares), and codex carries its bare selected id (`{modelId}`, an id the
+   * entry's `model` token pattern must be able to carry). Absent = the config
+   * alone selects the model (claude's env vars, opencode's blob). Applied by
+   * the session's respawn options through the entry's `legacyConfigField`,
+   * never by id.
    *
    * `contextLengthVar` (env kind only): the env var a discovered per-model context-window
    * size is written to when known (claude's `CLAUDE_CODE_MAX_CONTEXT_TOKENS`) — without it,

src/custom-model-hosts.ts

@@ -66,7 +66,8 @@ export interface CustomModelHost {
   modelContextLengths?: Record<string, number>;
   /**
    * Discovered number of parallel server slots per model id, keyed like `modelContextLengths`
-   * and populated on the same loaded-models-only basis. Read from the launch command's
+   * but populated only for models the server reports loaded (a listing never states a slot
+   * count, unlike `contextLengths`, which every entry can supply). Read from the launch command's
    * `--parallel`/`-np` when it states one, otherwise from llama.cpp's own `/props`
    * `total_slots` (a llama-server started without `--parallel` picks the count itself, so
    * the command cannot say). llama-server splits its context across these slots (by default
@@ -92,9 +93,12 @@ export interface CustomModelHost {
    */
   modelSizesGB?: Record<string, number>;
   /**
-   * User-set fallback context length (tokens), applied by the read sites in
-   * `session-routes.ts` only when `modelContextLengths` has no entry for the selected
-   * model (a gateway that states no per-model figure, a model never loaded yet). Never
+   * User-set fallback context length (tokens), applied via
+   * `resolveCustomModelContextLength()` at every read site (the swap route, the
+   * quick-start route, boot recovery) only when `modelContextLengths` has no entry for
+   * the selected model (a gateway that states no per-model figure, a model never loaded
+   * yet). It is the model's WHOLE window, never a per-slot figure: the Claude floor
+   * check divides it by any stored slot count exactly like a discovered figure. Never
    * written by discovery, so a value set in the endpoint editor survives every
    * re-discovery sweep; unset keeps the long-standing behaviour of letting each CLI
    * assume its own default.

src/session.ts

@@ -2724,7 +2724,8 @@ export class Session extends EventEmitter {
 
   /**
    * Force the custom-model selection's `launchModel` (pi/omp `custom/<id>`, grok's
-   * `[model.<name>]` block name) onto the CLI's `model` launch param. Where that param
+   * `[model.<name>]` block name, codex's bare selected id) onto the CLI's `model`
+   * launch param. Where that param
    * lives is registry DATA — the entry's `legacyConfigField` (`piConfig`, `grokConfig`,
    * ...) or the top-level `model` for an entry that declares none — so this stays a
    * generic reader rather than a branch per CLI. Applied on the OPTIONS only: the stored

src/web/public/i18n.js

@@ -616,8 +616,8 @@
     'Optional. Left blank on edit keeps the existing key.': '可选。编辑时留空将保留现有密钥。',
     'Auth header': '认证请求头',
     'Default context length (tokens)': '默认上下文长度（token 数）',
-    'Used for models whose size cannot be discovered. Leave empty to let each CLI assume its own default.':
-      '用于无法自动发现上下文大小的模型。留空则让各个 CLI 使用其自身的默认值。',
+    "Used for models whose size cannot be discovered. The model's whole window; the Claude floor check divides it by any stored slot count. Leave empty to let each CLI assume its own default.":
+      '用于无法自动发现上下文大小的模型。这是模型的完整窗口；Claude 下限检查会将其除以已存储的槽位数。留空则让各个 CLI 使用其自身的默认值。',
     'Never send both — some servers hang indefinitely.': '切勿同时发送两者 — 部分服务器会因此无限期挂起。',
     'Authorization: Bearer (default)': 'Authorization: Bearer（默认）',
     'api-key header (Azure)': 'api-key 请求头（Azure）',

src/web/public/index.html

@@ -2800,7 +2800,7 @@
                         <input type="text" id="customModelHostBaseUrl" class="set-input" placeholder="http://192.168.1.50:8080">
                       </div>
                       <div class="set-row has-field">
-                        <div class="set-row-text"><span class="set-row-label">Default context length (tokens)</span><span class="set-row-desc">Used for models whose size cannot be discovered. Leave empty to let each CLI assume its own default.</span></div>
+                        <div class="set-row-text"><span class="set-row-label">Default context length (tokens)</span><span class="set-row-desc">Used for models whose size cannot be discovered. The model's whole window; the Claude floor check divides it by any stored slot count. Leave empty to let each CLI assume its own default.</span></div>
                         <input type="number" id="customModelHostDefaultContextLength" class="set-input" min="1" max="100000000" step="1" placeholder="131072">
                       </div>
                       <div class="set-row has-field">

src/web/routes/custom-model-routes.ts

@@ -165,7 +165,7 @@ export interface DiscoveryResult {
    * over) any listed figure for the same model.
    */
   contextLengths: Record<string, number>;
-  /** See `CustomModelHost.modelSlotCounts`; populated on the same loaded-models-only basis as `contextLengths`. */
+  /** See `CustomModelHost.modelSlotCounts`; populated only for models the server reports loaded (launch command or `/props`). No listing states a slot count, unlike `contextLengths`. */
   slotCounts: Record<string, number>;
   /** See `CustomModelHost.modelSizesGB` — populated for every model whose own listing states one. */
   sizesGB: Record<string, number>;

src/web/routes/session-routes.ts

@@ -1611,7 +1611,8 @@ export function registerSessionRoutes(
     }
 
     // A CLI whose config alone cannot select the model also gets its `model` launch param
-    // forced (pi/omp `custom/<id>`, grok's block name). The argv engine DROPS a token that
+    // forced (pi/omp `custom/<id>`, grok's block name, and codex now carries its bare
+    // selected id too). The argv engine DROPS a token that
     // fails its pattern rather than quoting it, which would silently launch the CLI on its
     // own default provider again, so refuse an id the pattern cannot carry up front.
     const modelSpec = entry.launch.params.model;