Every basic-memory CLI invocation paid roughly 2 seconds of module-import
cost before any work started, which blew the Claude Code plugin's
SessionStart hook budget on cold machines (#886). The cost came from
module-level imports that pulled the entire server stack into CLI startup:
- mcp/async_client.py imported FastAPI at module level, so every consumer
of get_client() loaded FastAPI even for cloud-routed or help-only paths.
- mcp/clients/*.py imported call_* helpers from basic_memory.mcp.tools.utils,
which executes the whole tools package __init__ — every MCP tool module
plus fastmcp and the mcp SDK.
- mcp/project_context.py imported fastmcp.Context and ToolError eagerly.
- CLI command modules (tool, ci, schema) imported MCP tool functions at
module level; db and the import_* commands pulled SQLAlchemy/Alembic and
the markdown/file-service stack; status/doctor/orphans/command_utils
imported ToolError (the mcp SDK) and basic_memory.db.
- schemas/base.py imported dateparser (~0.13s) for one helper function.
The fix only defers imports to the point of use (no behavior changes):
FastAPI now loads inside _resolve_local_asgi_database alongside the
existing lazy api.app import, so it is only paid when a request actually
routes through the in-process ASGI transport; the typed clients import
call_* per method; project_context uses PEP 563 annotations with Context
under TYPE_CHECKING; the CLI command modules import their heavy
dependencies inside the command bodies. Tests that patched the old
module-level aliases now patch the source modules instead.
Measured on a warm cache (python -X importtime / wall time):
- import basic_memory.cli.main: 1.92s -> 0.45s
- bm --help: 2.40s -> 0.52s
- bm tool search-notes --help: 2.40s -> 0.86s
A regression test asserts that importing the CLI entry module with full
command registration leaves fastapi, sqlalchemy, alembic, fastmcp, mcp,
basic_memory.api.app, basic_memory.db, basic_memory.markdown,
basic_memory.mcp.tools, and basic_memory.services out of sys.modules.
Fixes#886
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Signed-off-by: phernandez <paul@basicmachines.co>
phernandez