Clarify taskHint behavior

Author: LucaButBoring

docs/specification/draft/basic/utilities/tasks.mdx

@@ -86,7 +86,12 @@ The set of capabilities in `capabilities.tasks.requests` is exhaustive. If a req
 
 Tool calls are given special consideration for the purpose of task augmentation. In the result of `tools/list`, tools declare support for tasks via `annotations.taskHint`.
 
-This is to be interpreted as a fine-grained layer in addition to capabilities. If a server's capabilities include `tasks.requests.tools.call: false`, then clients **MUST NOT** attempt to use task augmentation on that server's tools, even if they declare tool-level support via `annotations.taskHint`.
+This is to be interpreted as a fine-grained layer in addition to capabilities, following these rules:
+
+1. If a server's capabilities include `tasks.requests.tools.call: false`, then clients **MUST NOT** attempt to use task augmentation on that server's tools, even if they declare tool-level support via `annotations.taskHint`.
+1. If a server's capabilities include `tasks.requests.tools.call: true`, then clients consider the value of `taskHint`, and handle it accordingly:
+   1. If `taskHint` is not present or `false`, clients **MUST NOT** attempt to invoke the tool as a task. Servers **SHOULD** return a `-32601` (Method not found) error if a client attempts to do so.
+   1. If `taskHint` is `true`, clients **SHOULD** attempt to invoke the tool as a task. Servers **MAY** return a `-32601` (Method not found) error if a client does not attempt to do so.
 
 ## Protocol Messages