# Task Log - Fix Default Tenant Resolution

## Actions

- Investigated 404 error when accessing `/api/v1/tenants/default/knowledge-bases`.
- Identified that the WebUI sends `X-Tenant-ID: default` which caused UUID validation failure.
- Modified `lightrag/api/dependencies.py` to add `resolve_default_tenant` and `resolve_default_kb` helper functions.
- Updated `get_tenant_context` and `get_tenant_context_no_kb` to use these helpers to resolve "default" to the first available tenant/KB.
- Added a new test case to `test_multitenant.sh` to verify default tenant resolution.

## Decisions

- Decided to handle "default" resolution in the dependency layer to support existing clients (WebUI) without requiring client-side changes.
- Used `request.app.state.rag_manager` to access `TenantService` within the dependency.

## Results

- `test_multitenant.sh` passes all tests, including the new "Verify Default Tenant Resolution" test.
- Accessing `/api/v1/tenants/me` with `X-Tenant-ID: default` now returns the details of the first available tenant instead of a 400/404 error.