diff --git a/.planning/STATE.md b/.planning/STATE.md
index 242bcc5e8..4d370e566 100644
--- a/.planning/STATE.md
+++ b/.planning/STATE.md
@@ -19,19 +19,19 @@
 
 ## Current Position
 
-Phase: 14 of 14 (Researcher Agent)
-Plan: 3 of 3 in current phase
-Status: Complete
-Last activity: 2026-01-15 - Completed 14-03-PLAN.md
+Phase: 15 of 15 (Dedicated Planner Agent)
+Plan: 1 of 2 in current phase
+Status: In progress
+Last activity: 2026-01-16 - Completed 15-01-PLAN.md
 
-Progress: ████████████████████████████ 33/33 plans (100%)
+Progress: ██████████████████████████████ 34/35 plans (97%)
 
 ## Performance Metrics
 
 **Velocity:**
-- Total plans completed: 33
+- Total plans completed: 34
 - Average duration: 3.5 min
-- Total execution time: ~115 min
+- Total execution time: ~120 min
 
 **By Phase:**
 
@@ -51,9 +51,10 @@ Progress: ███████████████████████
 | 99 | 3 | 1 min | <1 min (parallel) |
 | 13 | 3 | 10 min | 3.3 min |
 | 14 | 3 | 11 min | 3.7 min |
+| 15 | 1 | 5 min | 5 min |
 
 **Recent Trend:**
-- Last 5 plans: 13-03 (4m), 14-01 (4m), 14-02 (4m), 14-03 (3m)
+- Last 5 plans: 14-01 (4m), 14-02 (4m), 14-03 (3m), 15-01 (5m)
 - Trend: Consistent execution times
 
 *Updated after each plan completion*
@@ -86,6 +87,8 @@ Progress: ███████████████████████
 | 14 | 902 lines from ~1,200 source (25% reduction) | Preserved all concepts while removing redundancy |
 | 14 | Thin orchestrator for /gsd:research-phase | Orchestrator 130 lines, expertise in agent |
 | 14 | Parallel agent spawning for /gsd:research-project | 4 agents (stack, features, architecture, pitfalls) maximize throughput |
+| 15 | 1,147 lines from ~3,580 source (68% reduction) | Complete planning methodology consolidated into single agent |
+| 15 | 14 sections covering full planning workflow | Includes discovery, task breakdown, dependency graph, goal-backward, checkpoints, TDD, gap closure |
 
 ### Deferred Issues
 
@@ -108,16 +111,17 @@ None yet.
 - Phase 12 added: Changelog & update awareness (remote changelog fetch, /gsd:whats-new, publish workflow integration)
 - Phase 13 added: Dedicated debug agent (gsd-debugger with baked-in expertise, thin orchestrator pattern)
 - Phase 14 added: Dedicated researcher agent (gsd-researcher with research methodology, tool strategy, output formats)
+- Phase 15 added: Dedicated planner agent (gsd-planner with planning expertise, refactor plan-phase to thin orchestrator)
 
 ## Project Alignment
 
-Last checked: 2026-01-15
-Status: COMPLETE
-Assessment: All 33 plans executed successfully across 14 phases.
+Last checked: 2026-01-16
+Status: IN PROGRESS
+Assessment: Phase 15 Plan 01 complete, Plan 02 (thin orchestrator refactor) remaining.
 Drift notes: None
 
 ## Session Continuity
 
-Last session: 2026-01-15
-Stopped at: Completed 14-03-PLAN.md (final plan)
+Last session: 2026-01-16
+Stopped at: Completed 15-01-PLAN.md
 Resume file: None
diff --git a/.planning/phases/15-dedicated-planner-agent/15-01-SUMMARY.md b/.planning/phases/15-dedicated-planner-agent/15-01-SUMMARY.md
new file mode 100644
index 000000000..a27c44508
--- /dev/null
+++ b/.planning/phases/15-dedicated-planner-agent/15-01-SUMMARY.md
@@ -0,0 +1,106 @@
+---
+phase: 15
+plan: 01
+subsystem: agents
+tags: [planner, agent, planning, methodology]
+
+dependency-graph:
+  requires: [13, 14]
+  provides: [gsd-planner-agent, consolidated-planning-methodology]
+  affects: [future-plan-phase-refactor]
+
+tech-stack:
+  added: []
+  patterns: [consolidated-agent, thin-orchestrator-pattern]
+
+key-files:
+  created: [agents/gsd-planner.md]
+  modified: []
+
+key-decisions:
+  - "14 sections covering complete planning workflow"
+  - "1,147 lines consolidated from ~3,580 lines of source material"
+  - "Follows gsd-debugger/gsd-researcher pattern"
+
+metrics:
+  duration: "5 min"
+  completed: "2026-01-16"
+---
+
+# Phase 15 Plan 01: Create gsd-planner Agent Summary
+
+**One-liner:** Consolidated ~3,580 lines of planning references into 1,147-line dedicated agent following gsd-debugger/gsd-researcher pattern.
+
+## Accomplishments
+
+1. **Created gsd-planner agent file** (`agents/gsd-planner.md`)
+   - Complete planning methodology baked into single agent file
+   - 1,147 lines (within 800-1200 target)
+   - 14 sections covering full planning workflow
+   - Follows established agent patterns from Phase 13-14
+
+2. **Consolidated planning methodology from source files:**
+   - `references/principles.md` - Solo developer + Claude workflow philosophy
+   - `workflows/plan-phase.md` - Full execution flow with 16 steps
+   - `templates/phase-prompt.md` - PLAN.md structure and frontmatter
+   - `references/plan-format.md` - Task anatomy and types
+   - `references/scope-estimation.md` - Context budget and split signals
+   - `references/checkpoints.md` - Checkpoint types and authentication gates
+   - `references/tdd.md` - TDD detection and plan structure
+   - `references/goal-backward.md` - Must-haves derivation process
+
+3. **Agent sections implemented:**
+   - `<role>` - Planning agent identity and responsibilities
+   - `<philosophy>` - Plans are prompts, quality degradation curve, ship fast
+   - `<discovery_levels>` - Levels 0-3 with triggers
+   - `<task_breakdown>` - Task anatomy, types, TDD detection
+   - `<dependency_graph>` - Wave analysis, vertical slices
+   - `<scope_estimation>` - Context budget, split signals, depth calibration
+   - `<plan_format>` - PLAN.md structure, frontmatter schema
+   - `<goal_backward>` - Truths, artifacts, key_links derivation
+   - `<checkpoints>` - Types, authentication gates, anti-patterns
+   - `<tdd_integration>` - When to use, plan structure, RED-GREEN-REFACTOR
+   - `<gap_closure_mode>` - Planning from verification gaps
+   - `<execution_flow>` - 16 steps from load_project_state to offer_next
+   - `<structured_returns>` - PLANNING COMPLETE, CHECKPOINT REACHED formats
+   - `<success_criteria>` - Standard mode and gap closure mode checklists
+
+## Technical Details
+
+**Source material (~3,580 lines):**
+- principles.md: ~73 lines
+- plan-phase.md: ~868 lines
+- phase-prompt.md: ~575 lines
+- plan-format.md: ~474 lines
+- scope-estimation.md: ~257 lines
+- checkpoints.md: ~789 lines
+- tdd.md: ~264 lines
+- goal-backward.md: ~287 lines
+
+**Consolidation result:**
+- 1,147 lines (68% reduction from source material)
+- Preserved all critical concepts
+- Eliminated redundancy between source files
+- Kept concise examples for each concept
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Commits
+
+| Commit | Type | Description |
+|--------|------|-------------|
+| 1f45bef | feat | Create gsd-planner agent file |
+
+## Next Phase Readiness
+
+**Ready for Plan 15-02:** Refactor plan-phase.md to thin orchestrator
+- gsd-planner agent contains all planning expertise
+- plan-phase.md can be reduced to ~200 lines orchestrator
+- Will spawn gsd-planner subagent for actual planning work
+
+**Dependencies satisfied:**
+- Agent file exists and is complete
+- All 14 sections verified present
+- Follows established pattern from gsd-debugger/gsd-researcher