[KM-567] docs: record Phase 3 Planner agent in PROGRESS.md

Add "What just shipped (2026-06-05 — Phase 3: Planner agent)" section: files
added under src/agents/planner/, the stub contracts pending reconciliation with
the lead (BusinessContext) and tool team (KM-608), and the next steps
(Orchestrator expansion + TaskRunner + Assembler).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

PROGRESS.md

@@ -2,11 +2,50 @@
 
 Persistent tracker mirroring the 42-item ownership table in `REPO_CONTEXT.md` "Team — division of work". Update as PRs land. Future Claude Code sessions read this to know what's already done.
 
-**Last updated**: 2026-05-12 ([NOTICKET] Cleanup PR landed: ChatHandler wired to chat.py, Phase 1 dual-write dropped from /ingest, on_catalog_rebuild_requested implemented, dead modules deleted, answer_agent→chatbot renamed, retrieval cache restored via RetrievalRouter, top_values added to ColumnStats, lifespan migration, knowledge_router removed)
+**Last updated**: 2026-06-05 (Phase 3 deliverable #2: Planner agent built under `src/agents/planner/` — see "What just shipped" below)
 **Current open PR**: `pr/1` — active. Cleanup PR committed and pushed.
 
 ---
 
+## What just shipped (2026-06-05 — Phase 3: Planner agent)
+
+First slow-path agent from `AGENT_ARCHITECTURE_CONTEXT_new.md` §7.3. A single LLM
+call turns BusinessContext + Catalog + ToolRegistry + question + Constraints into a
+validated, **static** `TaskList` (DAG of fully-specified tool-call chains). No
+replanning (INV-6); tool-agnostic against a registry contract (INV-7). Fast path
+(`agents/orchestration.py`, `agents/chatbot.py`, `query/`) untouched.
+
+**Files added** (`src/agents/planner/`):
+- `contracts.py` — **STUB** Pydantic contracts pending reconciliation: `BusinessContext`
+  (+KeyTerm/DataTableNote/DataColumnNote, lead's §7.1), `ToolSpec`/`ToolRegistry` (tool
+  team KM-608, §9.2), `ToolOutput` envelope (§8.1).
+- `schemas.py` — `CrispStage`, `ToolCall`, `Task`, `TaskList` (§7.3). No replan schemas.
+- `inputs.py` — `CatalogSummary` (condensed, PII `sample_values` nulled, `from_catalog`
+  builder + `render`) and `Constraints` (max_tasks=5, modeling_allowed=False).
+- `registry.py` — **STUB** v1 P0 registry: query_structured, retrieve_documents,
+  list_sources, describe_source, compute_median/stddev/percentile/mode, date_trunc.
+- `errors.py` — `PlannerError`, `PlannerValidationError`.
+- `prompt.py` + `config/prompts/planner.md` — system prompt (INV-1/6/7 + principles) +
+  per-call human content (context + catalog + tools + constraints + few-shots + question).
+- `examples.py` — two few-shots (A exploratory revenue-by-category; B descriptive
+  monthly-trend-by-region with date_trunc), built from the real `TaskList` schema.
+- `validator.py` — `PlannerValidator` running the 8 checks (§7.3); reuses the existing
+  `IRValidator` for inline `query_structured` IRs.
+- `service.py` — `PlannerService` + `plan_analysis(...)`: chain (mirrors
+  `query/planner/service.py`) + validate-and-retry loop (max 3, mirrors `QueryService`).
+
+**Tests added** (`tests/agents/planner/`, 30 passing + 1 gated): `test_schemas.py`,
+`test_inputs.py`, `test_validator.py` (one failure per check + happy paths),
+`test_service.py` (`_FakeChain` + retry), `test_golden_questions.py` (live eval gated on
+`RUN_PLANNER_EVAL=1`). `ruff check` clean on planner paths.
+
+**Open follow-ups (not blockers):** reconcile `BusinessContext` with the lead and
+`ToolRegistry`/`ToolSpec` + real tools with teammate (KM-608); "GPT mini" currently uses
+the configured 4o deployment (swap `azure_deployment` when a mini deployment exists). Next
+per the architecture doc: Orchestrator slow-path expansion + TaskRunner + Assembler.
+
+---
+
 ## Legend
 
 - `[x]` done and merged