refactor(custom-model): move the real-home link into the registry recipe

- linkFromRealHome/realHomeFallback on the configDir recipe; the apply consumer is generic and names no CLI
- lstat guard so boot-recovery re-applies survive a dangling link; symlink is best-effort
- resolve the real home from the session's own dirEnvVar override before the server's, threaded through both routes and boot recovery (Session.envOverrideValue)
- deepseek links profiles/sessions/settings.yaml; boot-recovery test covers the session lookup

src/config/cli-registry/schema.ts

@@ -286,6 +286,14 @@ const launchModelTemplate = z
   .regex(/^[a-zA-Z0-9._\-/:{}]+$/)
   .optional();
 
+/** One entry name under a CLI's real home, for `linkFromRealHome`: single path segment,
+ * leading alphanumeric, no traversal or hidden-dot escape. */
+const homeSegmentName = z
+  .string()
+  .min(1)
+  .max(40)
+  .regex(/^[a-zA-Z0-9][a-zA-Z0-9._-]*$/);
+
 const capabilitiesSchema = z
   .object({
     external: z.boolean(),
@@ -582,6 +590,12 @@ const capabilitiesSchema = z
           fileName: z.string().min(1).max(80),
           template: z.enum(['codex-toml', 'pi-models-json', 'omp-models-yml', 'grok-toml', 'deepseek-patch-json']),
           launchModel: launchModelTemplate,
+          // State that must survive the isolated-directory redirect, symlinked by name from
+          // the CLI's real home (deepseek: profiles/sessions/settings.yaml). Single path
+          // segments only — the consumer joins them, so a traversal here would escape the
+          // real home. See the field's comment in cli-registry/types.ts.
+          linkFromRealHome: z.array(homeSegmentName).max(8).optional(),
+          realHomeFallback: z.string().min(1).max(80).optional(),
         })
         .strict(),
       z.object({ kind: z.literal('unsupported') }).strict(),

src/config/cli-registry/stock.ts

@@ -1553,6 +1553,13 @@ const DEEPSEEK: CliEntry = {
       dirEnvVar: 'DSH_HOME',
       fileName: 'cordis.patch.yml',
       template: 'deepseek-patch-json',
+      // dsh keeps state in its home that the redirect must NOT swallow: `sessions` is the
+      // session-log root (deleting it would take the user's transcripts with it on clear/
+      // close), `profiles` are the installed bundles the patch composes over, and
+      // `settings.yaml` must keep applying. The generated home-level `cordis.patch.yml`
+      // deliberately replaces the user's own for the session rather than linking it.
+      linkFromRealHome: ['profiles', 'sessions', 'settings.yaml'],
+      realHomeFallback: '.dsh',
     },
   },
   overlays: {
@@ -1905,8 +1912,8 @@ const COPILOT: CliEntry = {
     // custom provider and drops the GitHub sign-in requirement; COPILOT_PROVIDER_TYPE defaults to
     // "openai", which is what a Codeman custom endpoint is (llama.cpp, vLLM, Ollama).
     // COPILOT_MODEL names the model and COPILOT_PROVIDER_MODEL_ID / _WIRE_MODEL default to it.
-    // The OpenAI-style route is `<base>/v1/chat/completions`, so the base gets the `/v1` suffix
-    // the same way deepseek's does. All four already match the COPILOT_ prefix allowlist, so
+    // The OpenAI-style route is `<base>/v1/chat/completions`, so the base gets the `/v1`
+    // suffix via appendV1Suffix below. All four already match the COPILOT_ prefix allowlist, so
     // they are privileged env keys below: a non-granted multi-user owner must not be able to
     // redirect the session's endpoint or credentials through plain envOverrides.
     customModelInjection: {

src/config/cli-registry/types.ts

@@ -856,19 +856,13 @@ export interface CliCapabilities {
    * reuses that file.
    *
    * `appendV1Suffix` (env kind only): the raw `endpoint.baseUrl` gets `withV1Suffix()`
-   * applied before being written to `baseUrlVar`, instead of being used verbatim.
-   * DeepSeek needs this and claude/gemini must NOT get it — a per-CLI asymmetry confirmed
-   * by reading each SDK's own request-building source, not assumed: DeepSeek Harness's
-   * bundled `@deepseek-ai/dsh-llm-deepseek` concatenates `${connection.baseURL}/chat/
-   * completions` with no `/v1` insertion of its own (its real public API base,
-   * `https://api.deepseek.com`, expects the caller's base URL to already carry any
-   * needed prefix), while llama-swap/llama.cpp only ever serves the OpenAI-conventional
-   * `/v1/chat/completions` — confirmed live: a bare `POST <baseUrl>/chat/completions`
-   * 404s, `POST <baseUrl>/v1/chat/completions` succeeds, and the harness's own error
-   * message template (`DeepSeek API error (HTTP ${status})`) reproduces the exact
-   * `HTTP_404` this feature originally shipped with unexplained. Claude Code's own SDK,
-   * by contrast, was already confirmed working end-to-end against the RAW `baseUrl` with
-   * no suffix — appending one there would be wrong, not just redundant.
+   * applied before being written to `baseUrlVar`, instead of being used verbatim. Only
+   * copilot declares it — its OpenAI-style route is `<base>/v1/chat/completions`, and a
+   * gateway saves the bare root. claude/gemini must NOT get it: Claude Code's own SDK was
+   * confirmed working end-to-end against the RAW `baseUrl`, so appending a suffix there
+   * would be wrong, not just redundant. The per-session config-file recipes do not need
+   * this flag at all — `renderConfigFile()` applies the suffix inside every template
+   * (deepseek's patch included), so no configDir entry carries a raw base URL.
    */
   customModelInjection:
     | {
@@ -890,6 +884,25 @@ export interface CliCapabilities {
         fileName: string;
         template: 'codex-toml' | 'pi-models-json' | 'omp-models-yml' | 'grok-toml' | 'deepseek-patch-json';
         launchModel?: string;
+        /**
+         * Names of entries under this CLI's REAL home that must be symlinked into the
+         * isolated directory after the generated file is written — the same trick
+         * `linkSharedProjectsDir()` plays for claude's `projects`. Declared for CLIs whose
+         * home carries state that must survive the redirect (deepseek's `sessions` transcript
+         * root and `profiles` bundles, plus `settings.yaml`, which would otherwise stop
+         * applying and — for `sessions` — get deleted by `removeConfigDir` on clear/close).
+         * Never include `fileName` itself: the generated file owns that name in the isolated
+         * directory, and a link there would write THROUGH into the user's real file.
+         * Consumed generically by custom-model-injection-apply.ts.
+         */
+        linkFromRealHome?: string[];
+        /**
+         * Fallback location of the CLI's real home, relative to the user's home directory
+         * (deepseek's `.dsh`), used only when neither the session's own `dirEnvVar` override
+         * nor the server's environment sets it. Required whenever `linkFromRealHome` is
+         * declared, so no consumer has to hardcode a per-CLI default of its own.
+         */
+        realHomeFallback?: string;
       }
     | { kind: 'unsupported' };
 }

src/custom-model-injection-apply.ts

@@ -10,7 +10,7 @@
  * cli-registry changes" requirement it was written against.
  */
 
-import { chmodSync, existsSync, mkdirSync, readFileSync, writeFileSync, rmSync, symlinkSync } from 'node:fs';
+import { chmodSync, existsSync, lstatSync, mkdirSync, readFileSync, writeFileSync, rmSync, symlinkSync } from 'node:fs';
 import { homedir, platform } from 'node:os';
 import { join, dirname } from 'node:path';
 import { dataPath } from './config/instance.js';
@@ -39,24 +39,70 @@ export function customModelConfigDir(sessionId: string): string {
  * covers a re-apply onto a file that already exists (`mode` only applies at
  * creation).
  */
-export function applyConfigDirInjection(baseDir: string, injection: ConfigDirInjection): Record<string, string> {
+export function applyConfigDirInjection(
+  baseDir: string,
+  injection: ConfigDirInjection,
+  /**
+   * The value this SESSION's own env overrides set for `injection.dirEnvVar`, when it
+   * set one — a user who relocated the CLI's real home (an allowlisted key like
+   * DSH_HOME) must have their state linked from THAT directory, not the server's.
+   */
+  sessionHomeOverride?: string
+): Record<string, string> {
   for (const file of injection.files) {
     const filePath = join(baseDir, file.relPath);
     mkdirSync(dirname(filePath), { recursive: true, mode: 0o700 });
     writeFileSync(filePath, file.content, { encoding: 'utf8', mode: 0o600 });
     chmodSync(filePath, 0o600);
   }
-  if (injection.dirEnvVar === 'DSH_HOME') {
-    // Reuse installed profile bundles without changing the user's profile or credentials.
-    const profiles = join(baseDir, 'profiles');
-    if (!existsSync(profiles)) {
-      const realHome = process.env.DSH_HOME?.trim() || join(homedir(), '.dsh');
-      symlinkSync(join(realHome, 'profiles'), profiles, platform() === 'win32' ? 'junction' : 'dir');
-    }
-  }
+  linkRealHomeEntries(baseDir, injection, sessionHomeOverride);
   return { [injection.dirEnvVar]: baseDir, ...injection.extraEnv };
 }
 
+/**
+ * Symlinks the registry recipe's `linkFromRealHome` entries out of the CLI's real home
+ * into the otherwise-isolated `baseDir`, so redirecting `dirEnvVar` moves only the
+ * generated config file and not the state that has to survive the session (deepseek:
+ * the `sessions` transcript root `removeConfigDir` would otherwise delete, the `profiles`
+ * bundles the patch composes over, and `settings.yaml`). Declared per entry in stock.ts —
+ * this consumer is recipe-driven and names no CLI itself.
+ *
+ * Home resolution: the session's own override first (unless it IS `baseDir` — a re-apply
+ * onto a session already holding a previous injection's value must not self-link), then
+ * the server's environment, then the recipe's `realHomeFallback`. No home resolvable =
+ * no links, same best-effort posture as `linkSharedProjectsDir()`.
+ */
+function linkRealHomeEntries(baseDir: string, injection: ConfigDirInjection, sessionHomeOverride?: string): void {
+  const names = injection.linkFromRealHome;
+  if (!names || names.length === 0) return;
+  const fromSession = sessionHomeOverride?.trim();
+  const realHome =
+    (fromSession && fromSession !== baseDir ? fromSession : undefined) ||
+    process.env[injection.dirEnvVar]?.trim() ||
+    (injection.realHomeFallback ? join(homedir(), injection.realHomeFallback) : undefined);
+  if (!realHome) return;
+  for (const name of names) {
+    linkRealHomeEntry(join(realHome, name), join(baseDir, name));
+  }
+}
+
+function linkRealHomeEntry(target: string, link: string): void {
+  // lstat, never existsSync: existsSync is false for a DANGLING link, and recovery
+  // re-applies on every restart, so the second pass would try to recreate the link and
+  // throw EEXIST. lstat answers for real entries, good links and dangling links alike.
+  try {
+    if (lstatSync(link)) return; // already linked (idempotent re-apply) or a real dir wrote one
+  } catch {
+    // ENOENT — nothing is here yet, the only state in which a link gets created
+  }
+  try {
+    symlinkSync(target, link, platform() === 'win32' ? 'junction' : 'dir');
+  } catch {
+    // best-effort only — a platform that refuses symlinks keeps the documented
+    // side effect for this session rather than failing the whole apply over it
+  }
+}
+
 /**
  * Real, shared Claude config directory Codeman's own host process runs under — honors
  * `CLAUDE_CONFIG_DIR` the same way `claude-credentials.ts`'s `claudeCredentialsPath()`
@@ -258,7 +304,13 @@ export function applyCustomModelInjection(
    * trust-dialog seed, and only when provided (boot recovery, which has no reason to
    * re-answer a dialog that already fired once, omits it rather than re-deriving it).
    */
-  workingDir?: string
+  workingDir?: string,
+  /**
+   * Reads one env var from the SESSION's own env overrides (single-key on purpose: the
+   * map carries credentials). Only the `configDir` kind uses it, to resolve the CLI's real
+   * home for `linkFromRealHome` from the session's value before the server's.
+   */
+  sessionEnvLookup?: (envVar: string) => string | undefined
 ): AppliedCustomModel | undefined {
   const injection = buildCustomModelInjection(entry, endpoint, modelId, contextLength);
   if (injection.kind === 'unsupported') return undefined;
@@ -291,6 +343,6 @@ export function applyCustomModelInjection(
     };
   }
   const configDir = customModelConfigDir(sessionId);
-  const envOverrides = applyConfigDirInjection(configDir, injection);
+  const envOverrides = applyConfigDirInjection(configDir, injection, sessionEnvLookup?.(injection.dirEnvVar));
   return { envOverrides, envKeys: Object.keys(envOverrides), configDir, launchModel: injection.launchModel };
 }

src/custom-model-injection.ts

@@ -87,6 +87,10 @@ export interface ConfigDirInjection {
    * `customModelInjection.launchModel` template, never hand-built per CLI.
    */
   launchModel?: string;
+  /** Carried from the registry recipe — see `cli-registry/types.ts` `linkFromRealHome`. */
+  linkFromRealHome?: string[];
+  /** Carried from the registry recipe — see `cli-registry/types.ts` `realHomeFallback`. */
+  realHomeFallback?: string;
 }
 
 export interface UnsupportedInjection {
@@ -143,7 +147,14 @@ export function buildCustomModelInjection(
     case 'configDir': {
       const { content, extraEnv } = renderConfigFile(cap.template, endpoint, modelId, apiKey, contextLength);
       return withLaunchModel(
-        { kind: 'configDir', dirEnvVar: cap.dirEnvVar, files: [{ relPath: cap.fileName, content }], extraEnv },
+        {
+          kind: 'configDir',
+          dirEnvVar: cap.dirEnvVar,
+          files: [{ relPath: cap.fileName, content }],
+          extraEnv,
+          ...(cap.linkFromRealHome ? { linkFromRealHome: cap.linkFromRealHome } : {}),
+          ...(cap.realHomeFallback ? { realHomeFallback: cap.realHomeFallback } : {}),
+        },
         cap.launchModel,
         modelId
       );

src/session.ts

@@ -1330,6 +1330,17 @@ export class Session extends EventEmitter {
     return value && value.trim() ? value.trim() : undefined;
   }
 
+  /**
+   * One env var from this session's overrides, for internal path resolution only
+   * (custom-model injection linking an isolated config dir back to a path that must
+   * survive lives in). Single-key lookup by design, like `deepSeekHomeOverride`: the
+   * map can hold provider credentials and stays off the public `SessionState`.
+   */
+  envOverrideValue(key: string): string | undefined {
+    const value = this._envOverrides?.[key];
+    return value && value.trim() ? value.trim() : undefined;
+  }
+
   /** Owning username in multi-user mode, else undefined. */
   get owner(): string | undefined {
     return this._owner;

src/web/routes/session-routes.ts

@@ -1618,7 +1618,8 @@ export function registerSessionRoutes(
       body.modelId,
       session.id,
       contextLength,
-      session.workingDir
+      session.workingDir,
+      (envVar) => session.envOverrideValue(envVar)
     );
     if (!applied) {
       return createErrorResponse(ApiErrorCode.OPERATION_FAILED, `${session.mode} has no known custom-model mechanism`);
@@ -4514,7 +4515,8 @@ export function registerSessionRoutes(
         customModel.modelId,
         qsCustomModelSessionId,
         cmContextLength,
-        workspacePath
+        workspacePath,
+        (envVar) => qsGatedEnvOverrides?.[envVar]
       );
       if (!cmApplied) {
         return createErrorResponse(ApiErrorCode.OPERATION_FAILED, `${mode} has no known custom-model mechanism`);

src/web/server.ts

@@ -1470,7 +1470,13 @@ export class WebServer extends EventEmitter {
         endpoint,
         saved.modelId,
         session.id,
-        endpoint.modelContextLengths?.[saved.modelId]
+        endpoint.modelContextLengths?.[saved.modelId],
+        // Boot recovery deliberately omits `workingDir` (no reason to re-answer a trust
+        // dialog that already fired once), so the session-env lookup rides in after it:
+        // a session with its own DSH_HOME override must link its config dir back to
+        // THAT home, not the server's, exactly like the routes do.
+        undefined,
+        (envVar) => session.envOverrideValue(envVar)
       )?.envOverrides;
     } catch (err) {
       console.warn('[WebServer] Failed to rebuild custom-model env on recovery:', err);