app/agents/shared/ is a sibling of anonymous_chat/podcaster/multi_agent_chat/
video_presentation, so it should only hold code shared across 2+ of those
agents. In practice podcaster and video_presentation import nothing from it,
and anonymous_chat needs only context + compaction + retry_after + web_search.
Everything else was multi_agent_chat-only (the boundary just passes through).
Move the multi_agent_chat-only cluster into multi_agent_chat/shared/ (files
moved verbatim via git rename; ~116 import sites rewritten):
errors, feature_flags, filesystem_selection, path_resolver, prompt_caching,
sandbox, llm_config, mention_resolver
middleware/busy_mutex, middleware/kb_persistence
busy_mutex/llm_config/mention_resolver are boundary-only but import the moved
modules, so they were folded in to avoid a backwards shared -> multi_agent_chat
dependency. main_agent builders now import the impls directly; the shared
middleware barrel keeps only the genuinely-shared compaction + retry_after.
Also delete the dead leftover shared/plugins and shared/skills dirs (live
copies already live under main_agent/).
Remaining in app/agents/shared/: context, system_prompt(+prompts), checkpointer,
middleware/{compaction,retry_after,dedup_tool_calls}, tools/. checkpointer and
system_prompt are boundary-only infra pending a dedicated home decision.
knowledge_search, memory_injection and scoped_model_fallback no longer
belong in the cross-agent kernel (app/agents/shared/middleware): they are
consumed only inside multi_agent_chat. Relocate each impl next to the
builder that uses it:
- knowledge_search.py -> multi_agent_chat/shared/middleware/ (genuinely
shared: its _render_priority_message feeds kb_context_projection, used by
both the main agent and the KB subagent)
- memory_injection.py -> multi_agent_chat/shared/middleware/ (beside its
memory.py builder)
- scoped_model_fallback.py -> multi_agent_chat/shared/middleware/resilience/
(beside fallback.py/bundle.py)
Impls moved verbatim (git rename). Builders/consumers now import the local
sibling; main_agent knowledge_priority imports the new shared path; shared
middleware barrel trimmed.
Tests: repoint imports; convert the knowledge_search monkeypatch targets
from brittle dotted-string form to object-based patching (monkeypatch.setattr
on the imported module), which is robust to import ordering. No behavior
change.
The concrete filesystem backends are consumed only by the MAC filesystem
layer (tools, path-resolution middleware, the resolver, skills backend) and
tests -- no external app code. Group them next to the filesystem middleware
they serve:
- filesystem_backends.py -> filesystem/backends/resolver.py
- middleware/kb_postgres_backend.py -> filesystem/backends/kb_postgres.py
- middleware/local_folder_backend.py -> filesystem/backends/local_folder.py
- middleware/multi_root_local_folder_backend.py -> .../multi_root_local_folder.py
- document_xml.py -> filesystem/backends/document_xml.py
Repoint all 21 importers. No behavior change; import-all + filesystem
backend/path-resolution/knowledge-search unit tests stay green (478).
permissions.py (authorization Rule/Ruleset model) is consumed across all
MAC subagents + the permissions middleware, with a single external
consumer (user_tool_allowlist service) -> move to
multi_agent_chat/shared/permissions.py and repoint all 42 sites.
deliverable_wait.py (wait_for_deliverable) is used only by the podcast and
video_presentation deliverable tools -> colocate into
subagents/builtins/deliverables/.
No behavior change; import-all + permission/allowlist/deliverable unit
tests stay green.
receipt.py (Receipt model + make_receipt) and receipt_command.py
(with_receipt Command helper) are a tight pair used only by MAC subagent
tools, the graph state, and the kb_persistence middleware -- no external
code imports them (the streaming tool_end handler only references them in a
docstring). Move both into a dedicated receipts/ package
(receipts/receipt.py + receipts/command.py) and repoint importers.
No behavior change; import-all + receipt/deliverable unit tests stay green.
filesystem_state.py (the multi-agent graph state) and state_reducers.py
(its merge reducers) are consumed only by multi_agent_chat (filesystem
tools/middleware, kb projection, and the MAC-only shared middleware) plus
two unit tests -- no external app code. Relocate them into a dedicated
multi_agent_chat/shared/state/ package (filesystem_state.py + reducers.py)
and repoint every importer.
No behavior change; import-all + the full unit/middleware + unit/agents
suites (1066 tests) stay green.
shared/tools/knowledge_base.py had exactly one production consumer: the
report deliverable, which imported it via `from .knowledge_base import ...`
-- a sibling path that did not exist, so the report KB-search path would
raise ImportError at runtime.
Move the module next to report.py (subagents/builtins/deliverables/tools/)
which makes that relative import valid, and move its only dependency
(shared/utils.py date helpers) to multi_agent_chat/shared/date_filters.py,
shared between the KB tool and the knowledge_search middleware.
Drop the now-unused knowledge-base re-exports from the shared/tools barrel
and repoint the integration tests. import-all + error-contract stay green.
Eliminate the top-level multi_agent_chat/middleware/ package so each slice
owns its middleware (vertical-slice colocation):
- middleware/shared/ -> shared/middleware/ (cross-slice middleware)
- middleware/subagent/ -> subagents/shared/middleware/ (subagent stack)
- main_agent/middleware/ already colocated in Slice A
The moved shared/ subtree is internally consistent (all relative imports
stay within it), so only external absolute refs were rewritten. The
subagent stack's ..shared.* relatives were promoted to absolute paths to
the new shared/middleware/ location.
multi_agent_chat/ root is now: main_agent/, shared/, subagents/.
Verified: 2430 unit tests pass, 1 skipped (baseline unchanged).
