Split out a ModelHint type for clarity

Author: jspahrsummers

schema/schema.ts

@@ -806,27 +806,15 @@ export interface ImageContent {
  */
 export interface ModelPreferences {
   /**
-   * Optional string hints to use for model selection. How these hints are
-   * interpreted depends on the key(s) in each record:
-   *
-   * - If the record contains a `name` key:
-   *    - The client SHOULD treat this as a substring of a model name; for example:
-   *        - `claude-3-5-sonnet` should match `claude-3-5-sonnet-20241022`
-   *        - `sonnet` should match `claude-3-5-sonnet-20241022`, `claude-3-sonnet-20240229`, etc.
-   *        - `claude` should match any Claude model
-   *    - The client MAY also map the string to a different provider's model name or a different model family, as long as it fills a similar niche; for example:
-   *        - `gemini-1.5-flash` could match `claude-3-haiku-20240307`
-   *
-   * All other keys are currently left unspecified by the spec and are up to the
-   * client to interpret.
+   * Optional hints to use for model selection.
    *
    * If multiple hints are specified, the client MUST evaluate them in order
    * (such that the first match is taken).
    *
    * The client SHOULD prioritize these hints over the numeric priorities, but
    * MAY still use the priorities to select from ambiguous matches.
    */
-  hints?: Record<"name" | string, string>[];
+  hints?: ModelHint[];
 
   /**
    * How much to prioritize cost when selecting a model. A value of 0 means cost
@@ -862,6 +850,35 @@ export interface ModelPreferences {
   intelligencePriority?: number;
 }
 
+/**
+ * Hints to use for model selection.
+ *
+ * - If the record contains a `name` key:
+ *    - The client SHOULD treat this as a substring of a model name; for example:
+ *        - `claude-3-5-sonnet` should match `claude-3-5-sonnet-20241022`
+ *        - `sonnet` should match `claude-3-5-sonnet-20241022`, `claude-3-sonnet-20240229`, etc.
+ *        - `claude` should match any Claude model
+ *    - The client MAY also map the string to a different provider's model name or a different model family, as long as it fills a similar niche; for example:
+ *        - `gemini-1.5-flash` could match `claude-3-haiku-20240307`
+ *
+ * Keys not declared here are currently left unspecified by the spec and are up
+ * to the client to interpret.
+ */
+export interface ModelHint {
+  /**
+   * A hint for a model name.
+   * 
+   * The client SHOULD treat this as a substring of a model name; for example:
+   *  - `claude-3-5-sonnet` should match `claude-3-5-sonnet-20241022`
+   *  - `sonnet` should match `claude-3-5-sonnet-20241022`, `claude-3-sonnet-20240229`, etc.
+   *  - `claude` should match any Claude model
+   * 
+   * The client MAY also map the string to a different provider's model name or a different model family, as long as it fills a similar niche; for example:
+   *  - `gemini-1.5-flash` could match `claude-3-haiku-20240307`
+   */
+  name?: string;
+}
+
 /* Autocomplete */
 /**
  * A request from the client to the server, to ask for completion options.