a few coach tidbits (#410)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **Documentation**
* Added a disclaimer that Virtual Coach responses may be AI-generated
and should be verified against assignments, course materials, and
instructor guidance.
* Expanded guidance with background on the AI powering the Coach,
identified the model provider, clarified that student PII is not stored
by the provider, and linked to supporting research.
* Highlighted supported use cases (error messages, summaries, hints) and
research-backed learning benefits.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: shajason

source/common/tools/student-virtual-coach.rst

@@ -9,6 +9,8 @@ Virtual Coach
 
 The Virtual Coach can help you understand the error messages you have received, gain a better understanding of the assignment prompt, or receive a hint about the next possible steps.
 
+.. note::
+   Virtual Coach responses may be AI-generated. Always verify suggestions against your assignment, course materials, and instructor guidance.
 
 To open Virtual Coach, click the Chatbot icon at the bottom-right corner of the screen. This icon will only be available if your teachers enable this feature.
 

source/instructors/setupcourses/assignment-settings/virtual-coach.rst

@@ -9,6 +9,11 @@ Virtual Coach
 
 When Virtual Coach is enabled, students can use AI to assist them with their programming tasks. Codio's prompts to the AI ensure that only assistance is provided, not solutions. The Virtual Coach can help students understand error messages they have received, gain a better understanding of the assignment prompt, or receive a hint about the next possible steps.
 
+Codio conducts extensive research in the field of AI use in computing education, with error messages, summaries, and hints representing well-researched use cases for AI-assisted learning. Our Coach feature, which generates AI-powered error messages, demonstrates positive benefits for learners through improved completion rates and higher median grade attainment. For more information, you can download `our research paper <https://www.codio.com/research/impact-of-codio-coach>`_.
+
+.. note::
+    Coach is powered by Anthropic's Claude model. No student's personally identifiable information (PII) is stored by Anthropic, ensuring student privacy protection. 
+
 In the assignments settings area, there are three settings you can toggle to enable the following features: **Summarize Prompt**, **Error Augmentation**, and **Next Steps Hint**.