test: add oversized test split plan (#3987)

* test: add oversized test split plan

* test: refresh oversized split plan

tests/OVERSIZED_TEST_SPLIT_PLAN.md

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+# Oversized Test File Split Plan
+
+## Purpose
+
+This document plans future oversized test-file splits using current repo data.
+It does not move files, rewrite assertions, extract helpers, or change CI.
+
+## Roadmap context
+
+- Issue: #3983
+- Parent tracker: #2523
+- Follows #3973 / #3982, the report-only order-sensitivity diagnostics slice.
+
+## Methodology
+
+Metrics were generated from the current test tree using:
+
+- physical line counts for every recursive `test_*.py` file under `tests/`;
+- AST counts for `test_*` functions and `Test*` classes;
+- one `pytest --collect-only -q tests` run to count collected items per file;
+- current taxonomy classification from `tests._taxonomy.classify_test_path`; and
+- static setup-signal scans for route/API, DB/session, import-state, security, filesystem, subprocess/script, async/threading, and UI/static indicators.
+
+Static signals are not proof of risk. They are review prompts.
+Future split PRs must still inspect each file manually before editing.
+
+## Current summary
+
+- test files scanned: 583
+- collected pytest items counted: 3586
+- large-file threshold: 300 lines
+- large-collected threshold: 20 collected items
+
+Area distribution:
+
+| Value | Files |
+|---|---:|
+| cli | 28 |
+| helpers | 1 |
+| js | 39 |
+| routes | 23 |
+| security | 77 |
+| services | 144 |
+| uncategorized | 234 |
+| unit | 37 |
+
+Sub-area distribution:
+
+| Value | Files |
+|---|---:|
+| api | 6 |
+| atomic | 3 |
+| auth | 9 |
+| calendar | 10 |
+| cli | 28 |
+| confinement | 7 |
+| cookbook | 13 |
+| document | 11 |
+| email | 12 |
+| embedding | 3 |
+| gallery | 5 |
+| history | 3 |
+| js | 39 |
+| llm | 16 |
+| mcp | 8 |
+| memory | 15 |
+| nondict | 7 |
+| nonstring | 22 |
+| owner | 14 |
+| owner_scope | 23 |
+| parse | 4 |
+| provider | 6 |
+| research | 16 |
+| route | 6 |
+| routes | 9 |
+| scheduler | 3 |
+| scope | 5 |
+| security | 9 |
+| session | 16 |
+| ssrf | 3 |
+| webhook | 3 |
+| xss | 5 |
+
+Values below 2 files: 244 values covering 244 files.
+
+## Top files by collected pytest items
+
+| File | Lines | Collected tests | Test defs | Test classes | Area | Sub-area | Signals |
+|---|---:|---:|---:|---:|---|---|---|
+| `tests/test_model_routes.py` | 1778 | 139 | 116 | 10 | routes | routes | route/api, db/session, import-state, async/threading |
+| `tests/test_security_regressions.py` | 1224 | 92 | 68 | 0 | security | security | route/api, db/session, import-state, security, filesystem, async/threading, ui/static |
+| `tests/test_provider_classification.py` | 188 | 67 | 21 | 4 | services | provider | - |
+| `tests/test_cookbook_helpers.py` | 912 | 65 | 65 | 0 | services | cookbook | route/api, filesystem, subprocess/script, async/threading, ui/static |
+| `tests/test_shell_routes.py` | 481 | 63 | 48 | 8 | routes | routes | route/api, import-state, filesystem |
+| `tests/test_pr_blocker_audit.py` | 964 | 58 | 58 | 0 | uncategorized | pr_blocker_audit | import-state, security, filesystem |
+| `tests/test_provider_endpoints.py` | 241 | 58 | 18 | 1 | services | provider | subprocess/script |
+| `tests/test_agent_loop.py` | 469 | 52 | 52 | 5 | uncategorized | agent_loop | db/session, import-state |
+| `tests/test_service_health.py` | 472 | 47 | 42 | 0 | uncategorized | service_health | async/threading |
+| `tests/test_run_focus.py` | 399 | 47 | 44 | 0 | uncategorized | run_focus | security, filesystem, subprocess/script, ui/static |
+| `tests/test_llm_core_temperature.py` | 196 | 41 | 17 | 0 | services | llm | - |
+| `tests/test_endpoint_probing.py` | 411 | 34 | 30 | 6 | uncategorized | endpoint_probing | route/api, db/session, import-state |
+| `tests/test_llm_core_anthropic_temp_omit.py` | 94 | 32 | 6 | 0 | services | llm | db/session |
+| `tests/test_chat_helpers.py` | 264 | 31 | 18 | 0 | uncategorized | chat_helpers | route/api |
+| `tests/test_provider_detection.py` | 148 | 31 | 31 | 5 | services | provider | - |
+| `tests/test_model_context.py` | 251 | 30 | 30 | 4 | uncategorized | model_context | db/session, import-state |
+| `tests/test_endpoint_resolver.py` | 148 | 30 | 30 | 6 | uncategorized | endpoint_resolver | - |
+| `tests/test_embedding_lanes.py` | 1104 | 29 | 29 | 0 | services | embedding | filesystem |
+| `tests/test_upload_limits_centralized.py` | 110 | 29 | 5 | 0 | uncategorized | upload_limits_centralized | import-state, filesystem |
+| `tests/test_email_oauth.py` | 580 | 28 | 25 | 0 | services | email | route/api, db/session, security, async/threading |
+| `tests/test_review_regressions.py` | 930 | 26 | 26 | 0 | uncategorized | review_regressions | route/api, db/session, import-state, filesystem, async/threading |
+| `tests/test_rename_user_owner_sync.py` | 686 | 26 | 26 | 0 | security | owner | route/api, db/session, import-state, filesystem, async/threading |
+| `tests/test_helpers_import_state.py` | 426 | 26 | 26 | 0 | helpers | helpers | route/api, db/session, import-state |
+| `tests/test_taxonomy.py` | 145 | 26 | 16 | 0 | uncategorized | taxonomy | security, ui/static |
+| `tests/test_tool_path_confinement.py` | 282 | 24 | 24 | 0 | security | confinement | import-state, filesystem, async/threading |
+| `tests/test_copilot.py` | 170 | 23 | 16 | 0 | uncategorized | copilot | - |
+| `tests/test_research_utils.py` | 97 | 23 | 23 | 2 | services | research | - |
+| `tests/test_api_chat_security.py` | 401 | 22 | 8 | 0 | security | security | route/api, db/session, import-state, filesystem, async/threading |
+| `tests/test_tool_support_heuristic.py` | 166 | 22 | 22 | 3 | uncategorized | tool_support_heuristic | - |
+| `tests/test_platform_compat.py` | 318 | 21 | 21 | 0 | uncategorized | platform_compat | import-state, filesystem, subprocess/script |
+
+## Top files by physical line count
+
+| File | Lines | Collected tests | Test defs | Test classes | Area | Sub-area | Signals |
+|---|---:|---:|---:|---:|---|---|---|
+| `tests/test_model_routes.py` | 1778 | 139 | 116 | 10 | routes | routes | route/api, db/session, import-state, async/threading |
+| `tests/test_security_regressions.py` | 1224 | 92 | 68 | 0 | security | security | route/api, db/session, import-state, security, filesystem, async/threading, ui/static |
+| `tests/test_embedding_lanes.py` | 1104 | 29 | 29 | 0 | services | embedding | filesystem |
+| `tests/test_pr_blocker_audit.py` | 964 | 58 | 58 | 0 | uncategorized | pr_blocker_audit | import-state, security, filesystem |
+| `tests/test_review_regressions.py` | 930 | 26 | 26 | 0 | uncategorized | review_regressions | route/api, db/session, import-state, filesystem, async/threading |
+| `tests/test_cookbook_helpers.py` | 912 | 65 | 65 | 0 | services | cookbook | route/api, filesystem, subprocess/script, async/threading, ui/static |
+| `tests/test_rename_user_owner_sync.py` | 686 | 26 | 26 | 0 | security | owner | route/api, db/session, import-state, filesystem, async/threading |
+| `tests/test_email_oauth.py` | 580 | 28 | 25 | 0 | services | email | route/api, db/session, security, async/threading |
+| `tests/test_api_token_routes.py` | 578 | 17 | 17 | 0 | routes | api_routes | route/api, db/session, import-state, async/threading |
+| `tests/test_shell_routes.py` | 481 | 63 | 48 | 8 | routes | routes | route/api, import-state, filesystem |
+| `tests/test_email_owner_scope.py` | 474 | 9 | 9 | 0 | security | owner_scope | route/api, db/session, filesystem, async/threading |
+| `tests/test_service_health.py` | 472 | 47 | 42 | 0 | uncategorized | service_health | async/threading |
+| `tests/test_agent_loop.py` | 469 | 52 | 52 | 5 | uncategorized | agent_loop | db/session, import-state |
+| `tests/test_kv_cache_invalidation_2927.py` | 463 | 8 | 8 | 0 | uncategorized | kv_cache_invalidation_2927 | route/api, db/session, import-state, async/threading |
+| `tests/test_helpers_import_state.py` | 426 | 26 | 26 | 0 | helpers | helpers | route/api, db/session, import-state |
+| `tests/test_endpoint_owner_scope_followup.py` | 414 | 11 | 11 | 0 | security | owner_scope | route/api, db/session, filesystem |
+| `tests/test_endpoint_probing.py` | 411 | 34 | 30 | 6 | uncategorized | endpoint_probing | route/api, db/session, import-state |
+| `tests/test_imap_leak_fixes.py` | 404 | 15 | 15 | 0 | uncategorized | imap_leak_fixes | route/api, db/session, security, filesystem |
+| `tests/test_companion_readonly.py` | 402 | 17 | 17 | 0 | uncategorized | companion_readonly | db/session, import-state |
+| `tests/test_api_chat_security.py` | 401 | 22 | 8 | 0 | security | security | route/api, db/session, import-state, filesystem, async/threading |
+| `tests/test_upload_handler_atomicity.py` | 401 | 9 | 9 | 0 | uncategorized | upload_handler_atomicity | filesystem, async/threading |
+| `tests/test_run_focus.py` | 399 | 47 | 44 | 0 | uncategorized | run_focus | security, filesystem, subprocess/script, ui/static |
+| `tests/test_auth_regressions.py` | 375 | 15 | 15 | 0 | security | auth | route/api, db/session, import-state, async/threading |
+| `tests/test_calendar_owner_scope.py` | 345 | 7 | 7 | 0 | security | owner_scope | route/api, db/session, import-state, filesystem, async/threading, ui/static |
+| `tests/test_null_owner_gates.py` | 342 | 20 | 20 | 0 | security | owner | route/api, db/session, import-state |
+| `tests/test_agent_migration_manifest.py` | 340 | 15 | 15 | 0 | uncategorized | agent_migration_manifest | import-state, filesystem |
+| `tests/test_calendar_recurrence.py` | 338 | 19 | 19 | 0 | services | calendar | - |
+| `tests/test_tool_policy.py` | 330 | 13 | 13 | 0 | uncategorized | tool_policy | import-state, async/threading |
+| `tests/test_workspace_confine.py` | 328 | 18 | 18 | 0 | uncategorized | workspace_confine | route/api, filesystem, subprocess/script, async/threading |
+| `tests/test_diffusion_server_security.py` | 325 | 14 | 14 | 0 | security | security | route/api, import-state, security, filesystem, async/threading, ui/static |
+
+## Split planning candidates
+
+This section is generated from metrics, not from manual judgement.
+Files are included when they meet at least one threshold:
+
+- at least 300 physical lines; or
+- at least 20 collected pytest items.
+
+These are planning candidates only. A later split PR still needs a focused manual review of each file before moving tests.
+
+| File | Why included | Setup/risk signals | Suggested handling |
+|---|---|---|---|
+| `tests/test_model_routes.py` | 1778 lines, 139 collected tests | route/api, db/session, import-state, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_security_regressions.py` | 1224 lines, 92 collected tests | route/api, db/session, import-state, security, filesystem, async/threading, ui/static | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_provider_classification.py` | 67 collected tests | No obvious setup signals from static scan. | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_cookbook_helpers.py` | 912 lines, 65 collected tests | route/api, filesystem, subprocess/script, async/threading, ui/static | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_shell_routes.py` | 481 lines, 63 collected tests | route/api, import-state, filesystem | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_pr_blocker_audit.py` | 964 lines, 58 collected tests | import-state, security, filesystem | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_provider_endpoints.py` | 58 collected tests | subprocess/script | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_agent_loop.py` | 469 lines, 52 collected tests | db/session, import-state | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_service_health.py` | 472 lines, 47 collected tests | async/threading | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_run_focus.py` | 399 lines, 47 collected tests | security, filesystem, subprocess/script, ui/static | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_llm_core_temperature.py` | 41 collected tests | No obvious setup signals from static scan. | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_endpoint_probing.py` | 411 lines, 34 collected tests | route/api, db/session, import-state | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_llm_core_anthropic_temp_omit.py` | 32 collected tests | db/session | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_chat_helpers.py` | 31 collected tests | route/api | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_provider_detection.py` | 31 collected tests | No obvious setup signals from static scan. | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_model_context.py` | 30 collected tests | db/session, import-state | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_endpoint_resolver.py` | 30 collected tests | No obvious setup signals from static scan. | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_embedding_lanes.py` | 1104 lines, 29 collected tests | filesystem | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_upload_limits_centralized.py` | 29 collected tests | import-state, filesystem | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_email_oauth.py` | 580 lines, 28 collected tests | route/api, db/session, security, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_review_regressions.py` | 930 lines, 26 collected tests | route/api, db/session, import-state, filesystem, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_rename_user_owner_sync.py` | 686 lines, 26 collected tests | route/api, db/session, import-state, filesystem, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_helpers_import_state.py` | 426 lines, 26 collected tests | route/api, db/session, import-state | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_taxonomy.py` | 26 collected tests | security, ui/static | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_tool_path_confinement.py` | 24 collected tests | import-state, filesystem, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_copilot.py` | 23 collected tests | No obvious setup signals from static scan. | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_research_utils.py` | 23 collected tests | No obvious setup signals from static scan. | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_api_chat_security.py` | 401 lines, 22 collected tests | route/api, db/session, import-state, filesystem, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_tool_support_heuristic.py` | 22 collected tests | No obvious setup signals from static scan. | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_platform_compat.py` | 318 lines, 21 collected tests | import-state, filesystem, subprocess/script | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_context_compactor.py` | 21 collected tests | db/session, import-state, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_prompt_security.py` | 21 collected tests | No obvious setup signals from static scan. | Good first manual-review candidate if test themes are cohesive. |
+| `tests/test_null_owner_gates.py` | 342 lines, 20 collected tests | route/api, db/session, import-state | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_youtube_handler_consolidation.py` | 20 collected tests | route/api, import-state | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_calendar_recurrence.py` | 338 lines | No obvious setup signals from static scan. | Plan split boundaries before editing. |
+| `tests/test_workspace_confine.py` | 328 lines | route/api, filesystem, subprocess/script, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_api_token_routes.py` | 578 lines | route/api, db/session, import-state, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_companion_readonly.py` | 402 lines | db/session, import-state | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_set_admin.py` | 317 lines | route/api, import-state, filesystem, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_imap_leak_fixes.py` | 404 lines | route/api, db/session, security, filesystem | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_auth_regressions.py` | 375 lines | route/api, db/session, import-state, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_agent_migration_manifest.py` | 340 lines | import-state, filesystem | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_diffusion_server_security.py` | 325 lines | route/api, import-state, security, filesystem, async/threading, ui/static | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_tool_policy.py` | 330 lines | import-state, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_endpoint_owner_scope_followup.py` | 414 lines | route/api, db/session, filesystem | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_upload_routes_owner_scope.py` | 315 lines | route/api, filesystem, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_email_owner_scope.py` | 474 lines | route/api, db/session, filesystem, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_upload_handler_atomicity.py` | 401 lines | filesystem, async/threading | Plan split boundaries before editing. |
+| `tests/test_kv_cache_invalidation_2927.py` | 463 lines | route/api, db/session, import-state, async/threading | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_calendar_owner_scope.py` | 345 lines | route/api, db/session, import-state, filesystem, async/threading, ui/static | Defer mechanical split until setup/risk boundaries are mapped. |
+| `tests/test_skills_manager_owner_isolation.py` | 306 lines | import-state, filesystem | Defer mechanical split until setup/risk boundaries are mapped. |
+
+## Taxonomy coverage gaps among split candidates
+
+`uncategorized` is a current taxonomy area, not a builder failure.
+This plan does not reclassify tests because taxonomy changes should be reviewed separately from oversized-file split planning.
+
+Before using any of these files as a split target, first decide whether the taxonomy should be refined in a separate focused issue/PR.
+
+| File | Lines | Collected tests | Sub-area | Signals | Suggested follow-up |
+|---|---:|---:|---|---|---|
+| `tests/test_pr_blocker_audit.py` | 964 | 58 | pr_blocker_audit | import-state, security, filesystem | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_agent_loop.py` | 469 | 52 | agent_loop | db/session, import-state | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_service_health.py` | 472 | 47 | service_health | async/threading | Review taxonomy mapping before using as a split target. |
+| `tests/test_run_focus.py` | 399 | 47 | run_focus | security, filesystem, subprocess/script, ui/static | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_endpoint_probing.py` | 411 | 34 | endpoint_probing | route/api, db/session, import-state | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_chat_helpers.py` | 264 | 31 | chat_helpers | route/api | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_model_context.py` | 251 | 30 | model_context | db/session, import-state | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_endpoint_resolver.py` | 148 | 30 | endpoint_resolver | - | Review taxonomy mapping before using as a split target. |
+| `tests/test_upload_limits_centralized.py` | 110 | 29 | upload_limits_centralized | import-state, filesystem | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_review_regressions.py` | 930 | 26 | review_regressions | route/api, db/session, import-state, filesystem, async/threading | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_taxonomy.py` | 145 | 26 | taxonomy | security, ui/static | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_copilot.py` | 170 | 23 | copilot | - | Review taxonomy mapping before using as a split target. |
+| `tests/test_tool_support_heuristic.py` | 166 | 22 | tool_support_heuristic | - | Review taxonomy mapping before using as a split target. |
+| `tests/test_platform_compat.py` | 318 | 21 | platform_compat | import-state, filesystem, subprocess/script | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_context_compactor.py` | 233 | 21 | context_compactor | db/session, import-state, async/threading | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_youtube_handler_consolidation.py` | 104 | 20 | youtube_handler_consolidation | route/api, import-state | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_workspace_confine.py` | 328 | 18 | workspace_confine | route/api, filesystem, subprocess/script, async/threading | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_companion_readonly.py` | 402 | 17 | companion_readonly | db/session, import-state | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_set_admin.py` | 317 | 17 | set_admin | route/api, import-state, filesystem, async/threading | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_imap_leak_fixes.py` | 404 | 15 | imap_leak_fixes | route/api, db/session, security, filesystem | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_agent_migration_manifest.py` | 340 | 15 | agent_migration_manifest | import-state, filesystem | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_tool_policy.py` | 330 | 13 | tool_policy | import-state, async/threading | Review taxonomy and setup/risk boundaries before any split. |
+| `tests/test_upload_handler_atomicity.py` | 401 | 9 | upload_handler_atomicity | filesystem, async/threading | Review taxonomy mapping before using as a split target. |
+| `tests/test_kv_cache_invalidation_2927.py` | 463 | 8 | kv_cache_invalidation_2927 | route/api, db/session, import-state, async/threading | Review taxonomy and setup/risk boundaries before any split. |
+
+## Suggested first manual-review candidates
+
+These are not automatic split approvals. They are categorized candidates with enough size/collection value and no route/API, DB/session, import-state, or security signal from the static scan.
+
+Files still in the `uncategorized` taxonomy area are listed separately below so taxonomy review does not get mixed into the first split decision.
+
+| File | Lines | Collected tests | Area | Sub-area | Signals | Why this is a candidate |
+|---|---:|---:|---|---|---|---|
+| `tests/test_provider_classification.py` | 188 | 67 | services | provider | - | 67 collected tests |
+| `tests/test_provider_endpoints.py` | 241 | 58 | services | provider | subprocess/script | 58 collected tests |
+| `tests/test_llm_core_temperature.py` | 196 | 41 | services | llm | - | 41 collected tests |
+| `tests/test_provider_detection.py` | 148 | 31 | services | provider | - | 31 collected tests |
+| `tests/test_embedding_lanes.py` | 1104 | 29 | services | embedding | filesystem | 1104 lines, 29 collected tests |
+| `tests/test_research_utils.py` | 97 | 23 | services | research | - | 23 collected tests |
+| `tests/test_prompt_security.py` | 203 | 21 | security | security | - | 21 collected tests |
+| `tests/test_calendar_recurrence.py` | 338 | 19 | services | calendar | - | 338 lines |
+
+## High-risk candidates to defer first
+
+These files may still be split later, but not as the first implementation slice without a separate manual boundary review.
+
+| File | Lines | Collected tests | High-risk signals |
+|---|---:|---:|---|
+| `tests/test_model_routes.py` | 1778 | 139 | db/session, import-state, route/api |
+| `tests/test_security_regressions.py` | 1224 | 92 | db/session, import-state, route/api, security |
+| `tests/test_cookbook_helpers.py` | 912 | 65 | route/api |
+| `tests/test_shell_routes.py` | 481 | 63 | import-state, route/api |
+| `tests/test_pr_blocker_audit.py` | 964 | 58 | import-state, security |
+| `tests/test_agent_loop.py` | 469 | 52 | db/session, import-state |
+| `tests/test_run_focus.py` | 399 | 47 | security |
+| `tests/test_endpoint_probing.py` | 411 | 34 | db/session, import-state, route/api |
+| `tests/test_llm_core_anthropic_temp_omit.py` | 94 | 32 | db/session |
+| `tests/test_chat_helpers.py` | 264 | 31 | route/api |
+| `tests/test_model_context.py` | 251 | 30 | db/session, import-state |
+| `tests/test_upload_limits_centralized.py` | 110 | 29 | import-state |
+| `tests/test_email_oauth.py` | 580 | 28 | db/session, route/api, security |
+| `tests/test_review_regressions.py` | 930 | 26 | db/session, import-state, route/api |
+| `tests/test_rename_user_owner_sync.py` | 686 | 26 | db/session, import-state, route/api |
+
+## Rules for future split PRs
+
+- One file or one coherent file-family per PR.
+- No assertion rewrites mixed with file moves.
+- No helper extraction mixed with file moves.
+- No production code changes.
+- No CI workflow changes.
+- Preserve existing markers and taxonomy unless the split issue explicitly says otherwise.
+- Validate the original file's collected tests before and after the split.
+- Validate any neighboring taxonomy/focused-runner behavior if paths change.
+- Treat files with route/API, DB/session, import-state, or security signals as higher-risk until manually reviewed.
+
+## Suggested next step
+
+Use this plan to choose the first actual oversized-file split issue.
+The first split should prefer a file with high review value and low setup risk.
+Do not start a split PR from this planning issue alone if the file's boundaries are still ambiguous.
+
+## Reproduction command
+
+This document was generated with:
+
+```bash
+.venv/bin/python tests/tools/build_oversized_test_split_plan.py
+```
+
+## Freshness check
+
+After editing the builder or rebasing the branch, regenerate the plan and confirm no unexpected plan drift:
+
+```bash
+.venv/bin/python tests/tools/build_oversized_test_split_plan.py
+git diff --exit-code -- tests/OVERSIZED_TEST_SPLIT_PLAN.md
+```