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+# Task: Diagnose reasoning-effort client capability
+
+## Identity
+
+- Task ID: 20260901-reasoning-effort-client-diagnosis-b6c4e1a2
+- Mode: Feature
+- Branch: main
+- Worktree: D:\Datas\OthersProjects\makelore
+- Base commit: 850947c092892cb647c4191b6d8bbf37a763e1ad
+- Owner: codex
+- Status: Ready for integration
+
+## Scope
+
+- Diagnose why the current AI Programming model menu exposes only one reasoning
+  strength for a model that is expected to support multiple strengths.
+- Trace the committed Makelore chain from model/provider capability metadata through
+  Conversation state, Pi runtime mapping, Snapshot projection, and Renderer options.
+- Build and run a deterministic focused reproduction for the exact menu symptom.
+- Report the verified boundary and the smallest coordinated repair scope; do not
+  modify product behavior unless the user separately asks for a fix.
+
+## Intent And Constraints
+
+- Treat the current Pi 0.84.2 hard-cutover architecture and Main-owned Provider
+  boundary as authoritative; do not restore OpenCode or add a compatibility layer.
+- Distinguish committed source behavior, deployed/model-provider behavior, and
+  unverified assumptions. The screenshot proves the visible symptom only.
+- Keep credentials, real user data, and upstream payloads out of diagnostics.
+- Preserve concurrent task ownership. The potentially related historical model-parity
+  peer has no defined scope, so this task remains read-only outside its own record.
+- The one-api repository is separately gated; do not inspect its occupied worktree or
+  initialize missing project-doc assets without authorization.
+
+## Outcome
+
+- Confirmed the direct cause in `shared/imported-model-profile.ts`: the
+  `deepseek-v4-pro` profile marks `off`, `minimal`, `low`, and `medium` as
+  unsupported (`null`) and maps only product `high` to provider `high`.
+- Confirmed Pi 0.84.2 filters every `null` level and exposes `xhigh`/`max` only when
+  those keys exist. The committed profile therefore deterministically projects the
+  single level `['high']`.
+- Confirmed the Main/runtime and Renderer chain is behaving as designed: provider
+  config copies the profile map, the Pi session reports its supported levels, and
+  the composer renders only levels in that runtime list. The Renderer is not
+  dropping additional options.
+- Confirmed the local AI proxy forwards the original JSON request body to one-api;
+  it does not remove `reasoning_effort`.
+- A one-variable diagnostic map exposed `off`, `low`, `medium`, and `high`, and the
+  real Pi serializer emitted provider values `low`, `high`, and `max` for product
+  `low`, `medium`, and `high` respectively. This proves the repair seam without
+  changing production behavior.
+- The product contract currently has only `off|minimal|low|medium|high`; literal
+  `xhigh`/`max` menu labels require a separate contract/UI expansion. Mapping the
+  existing product `high` to provider `max` avoids that expansion if those product
+  semantics are accepted.
+- No product code or canonical project documentation was changed. Temporary
+  diagnostic tests were removed after use.
+
+## Verification
+
+- Deterministic red reproduction, run three times:
+  `pnpm exec vitest run tests/unit/diagnostic-deepseek-v4-reasoning.test.ts --maxWorkers=1`
+  -> each run failed with expected `['off','low','medium','high']` versus actual
+  `['high']`.
+- One-variable causal test using only a replacement level map -> passed and returned
+  `['off','low','medium','high']`.
+- Real Pi payload serialization diagnostic -> `3 passed`; product
+  `low -> low`, `medium -> high`, and `high -> max`, with thinking enabled.
+- Focused proxy diagnostic with `reasoning_effort: 'max'` -> passed; the temporary
+  assertion was reverted.
+- Final existing-suite check:
+  `pnpm exec vitest run tests/unit/imported-model-profile.test.ts tests/unit/pi-provider-config.test.ts tests/unit/coding-feature-ui.test.tsx tests/unit/ai-proxy-routes.test.ts --maxWorkers=1`
+  -> `4` files and `50` tests passed.
+
+## Follow-ups
+
+- Update the `deepseek-v4-pro` profile and its focused tests after confirming the
+  desired product labels. The smallest compatible map is expected to expose product
+  low/medium/high while translating to provider low/high/max.
+- If the UI must display literal `max` (or `xhigh`) rather than translating the
+  existing `high`, extend `ThinkingLevel`, IPC/runtime contracts, labels, and tests
+  as one coordinated change.
+- A server-owned capability descriptor can reduce future profile staleness, but is
+  a larger ownership change and is not needed for the immediate fix.
+
+## Promotion Candidates
+
+- None. Promote a durable capability-ownership rule only with an implemented repair
+  or accepted server/client contract design.