Attach a small JSON object as top-level userMetadata when creating a session, or update it on the session resource. Metadata is application data; do not put passwords, tokens or payment details in it.
curl -X POST "https://api.tooluse.net/v1/browsers/sessions/$SESSION_ID" \
-H "Authorization: Bearer $TOOLUSE_API_KEY" \
-H "Content-Type: application/json" \
-d '{"userMetadata":{"workflow":"checkout","case":"example-001"}}'
Read the session back to inspect the stored metadata. Session listing supports bounded metadata filters; use the generated schema for the exact query format.
curl "https://api.tooluse.net/v1/browsers/sessions/$SESSION_ID" \
-H "Authorization: Bearer $TOOLUSE_API_KEY"