Why: pip --report - mixes Collecting progress and the JSON document on stdout, so the first base-layer resolve failed before any wheel was stored.
Evidence: go test ./internal/execenv/ passed on this worktree (SELF). A live dry-run of python-docx showed the progress text before the JSON object.
Impact: resolve reads report.json and ignores the progress stream. Package selection is unchanged.
Refs: Agent-System-Backend PR 207
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: The sandbox hides the host home directory and has no network, so pip install --user cannot supply python-docx, and the service PATH resolved python3 to a linuxbrew path that does not exist inside the sandbox.
Evidence: SELF go test of execenv, tools, store, app, server, runmgr, config, and cmd/agent-system on this worktree. CI has not run.
Impact: Sessions inherit a read-only base layer. Extra packages are requested through python_env, auto-approved only from the allowlist, and mounted per conversation. Schema 35 adds the request and binding tables.
Refs: .task/feature-layered-python-env.md
Co-authored-by: Cursor <cursoragent@cursor.com>