update skill and index for persistence

.claude/skills/hf-space-sandbox/SKILL.md

@@ -27,12 +27,38 @@ uv run scripts/sandbox.py status user/sandbox
 ssh USERNAME-SPACENAME@ssh.hf.space
 ```
 
-For example, for space `burtenshaw/sandbox`, use:
+For space `burtenshaw/sandbox`, the host is `burtenshaw-sandbox@ssh.hf.space`.
+
+## Persistent State
+
+Use files in `/app` for state that survives across commands:
+
+**Set a variable:**
+```bash
+ssh USERNAME-SPACENAME@ssh.hf.space "echo 42 > /app/foo"
+```
+
+**Read it back:**
+```bash
+ssh USERNAME-SPACENAME@ssh.hf.space "cat /app/foo"
+```
+
+**Run a background job:**
+```bash
+ssh USERNAME-SPACENAME@ssh.hf.space "nohup python train.py > /app/train.log 2>&1 &"
+```
+
+**Check progress:**
+```bash
+ssh USERNAME-SPACENAME@ssh.hf.space "tail /app/train.log"
+```
+
+**Environment variables (source a file):**
 ```bash
-ssh burtenshaw-sandbox@ssh.hf.space
+ssh USERNAME-SPACENAME@ssh.hf.space "echo 'export FOO=42' >> /app/.env"
+ssh USERNAME-SPACENAME@ssh.hf.space "source /app/.env && echo \$FOO"
 ```
 
-Add your SSH key at https://huggingface.co/settings/keys first.
 
 ## Run uv Scripts
 

index.html

@@ -61,15 +61,18 @@
         <h2>create sandbox</h2>
         <div class="prompt">create a sandbox called my-sandbox on hugging face</div>
 
-        <h2>set a variable</h2>
-        <div class="prompt">set FOO=bar in the sandbox</div>
+        <h2>store a value</h2>
+        <div class="prompt">save 42 to a file called foo in the sandbox</div>
 
-        <h2>echo variable</h2>
-        <div class="prompt">echo the value of FOO from the sandbox</div>
+        <h2>read it back</h2>
+        <div class="prompt">read the value of foo from the sandbox</div>
 
         <h2>run uv script</h2>
         <div class="prompt">run a python script that prints "hello" using requests</div>
 
+        <h2>background job</h2>
+        <div class="prompt">run train.py in the background and save output to a log file</div>
+
     </div>
 </body>
 </html>