# Proposal: Config Profile Multi-Repo Mounts

## Context

Config Profiles allow users to mount external Git repositories into tool instances via `git_mounts`. Currently, each `git_mount` entry supports only **one** source_path → target_path mapping. If a user wants to mount multiple directories from the same repository (e.g., a monorepo), they must add multiple entries, each cloning the repository independently.

## Goal

Enable a single `git_mount` entry to declare **multiple** source/target mappings from the same repository, while cloning the repository only once per entry.

## Direction

**Direction A: `mappings` array with backward compatibility**

Add an optional `mappings` array to each `git_mount` entry. The repository is cloned once, and each mapping creates a separate bind mount from a subdirectory of the cloned repo.

If `mappings` is absent, the existing `source_path` + `target_path` fields are treated as a single mapping (backward-compatible).

## Acceptance Criteria

1. A `git_mount` entry can specify `mappings: [{"source_path": "...", "target_path": "..."}, ...]`
2. The repository is cloned **exactly once** per `git_mount` entry
3. Each mapping creates a separate Docker bind mount from the cloned repo subdirectory
4. Existing profiles with `source_path`/`target_path` continue working without migration
5. The Config Profile editor UI supports adding/removing mappings per git mount
6. Glob patterns are supported in `source_path` within mappings
7. Relative `target_path` values are resolved against `working_directory` as before

## Out of Scope

- Cross-entry repo deduplication (two separate git_mount entries with the same `remote_url` still clone twice)
- SSH key per-repo configuration (can be added later)
- Sparse checkout / partial clone optimization
- Mounting from non-Git sources

## Risks

| Risk | Mitigation |
|------|------------|
| Schema migration complexity | No migration needed — backward-compatible |
| Frontend UI complexity | Nested form with add/remove mapping buttons |
| Clone directory sharing race condition | Each entry gets its own clone directory (url_hash based) |
| Large monorepo clone time | Out of scope — full clone is existing behavior |

## Related Artifacts

- Exploration: `openspec/explorations/config-profile-multi-repo-mounts.md`
- Spec: `openspec/specs/config-profile-multi-repo-mounts.md`
- Design: `openspec/designs/config-profile-multi-repo-mounts.md`
- Tasks: `openspec/tasks/config-profile-multi-repo-mounts.md`