diff --git a/.squad/agents/eecom/history.md b/.squad/agents/eecom/history.md
index b4007c402..7fce94c9c 100644
--- a/.squad/agents/eecom/history.md
+++ b/.squad/agents/eecom/history.md
@@ -103,3 +103,22 @@ CLI completeness audit (2026-03-08) confirmed: 26 primary commands routed in cli
 Implemented Flight's privacy-first adoption monitoring strategy on PR #326 branch. Moved `.squad/adoption/` → `.github/adoption/` for better GitHub integration. Stripped tracking.md to aggregate-only metrics (removed all individual repo names/URLs). Updated GitHub Action workflow (adoption-report.yml) and monitoring script (scripts/adoption-monitor.mjs) to write reports to `.github/adoption/reports/`. Removed "Built with Squad" showcase link from README.md (deferred to Tier 2 opt-in feature). This honors the principle: collect aggregate metrics via public APIs, but never publish individual repo lists without explicit consent. Test discipline: verified npm run build passes; docs-build.test.ts passed structure tests (Astro build failure unrelated to changes). Committed with clear message explaining privacy rationale.
 
 📌 **Team update (2026-03-10T12-55-49Z):** Adoption tracking Tier 1 complete and merged to decisions.md. Privacy-first architecture confirmed: aggregate metrics only, opt-in for individual repos, public showcase only when 5+ projects opt in. Append-only file governance enforced (no deletions in history.md or decisions.md). Microsoft ampersand style guide adopted for documentation.
+
+### Economy Mode Implementation (#500) (2026-03-20)
+
+**Context:** Issue #500 requested economy mode — a session-level and persistent modifier that shifts model selection to cheaper alternatives.
+
+**Architecture decision:** Economy mode is a Layer 3/4 modifier only. Layers 0–2 (explicit user preferences: config.json, session directive, charter) are never downgraded. This preserves user intent while enabling cost savings on auto-selected tasks.
+
+**Implementation:**
+1. `ECONOMY_MODEL_MAP` + `applyEconomyMode()` in `config/models.ts` — pure mapping function for premium→standard and standard→fast downgrades
+2. `readEconomyMode()` + `writeEconomyMode()` — config.json read/write functions (same merge-without-clobber pattern as `writeModelPreference()`)
+3. `resolveModel()` in `config/models.ts` updated with `economyMode?: boolean` option; falls back to reading from `squadDir` if not provided
+4. `resolveModel()` in `agents/model-selector.ts` updated with `economyMode?: boolean` — both SDK resolvers are economy-aware
+5. `squad economy [on|off]` command in CLI for persistent toggle
+6. `--economy` global flag in `cli-entry.ts` sets `SQUAD_ECONOMY_MODE=1` env var for session scope
+7. 34 new tests in `test/economy-mode.test.ts` — all pass
+
+**Key pattern:** Both resolveModel implementations follow identical principle: explicit overrides (user choice) are sacred; economy only affects computed auto-selection.
+
+**PR:** #500 branch `squad/500-economy-mode`
diff --git a/.squad/agents/procedures/history.md b/.squad/agents/procedures/history.md
index 2390dfc70..ea52095bf 100644
--- a/.squad/agents/procedures/history.md
+++ b/.squad/agents/procedures/history.md
@@ -80,3 +80,25 @@
 
 **Pattern:** NEVER/ALWAYS sections in charters compress well — fold bullet lists into single-paragraph summaries. Essential workflow details (Scribe's commit steps) should stay verbose.
 
+### 2026-03-22: Economy mode skill and personal squad governance (#500, #344)
+
+**Task:** Two governance tasks — economy mode skill design and personal squad coordinator awareness.
+
+**Economy mode (SKILL.md):**
+- Created `.squad/skills/economy-mode/SKILL.md` as a Layer 3 modifier, not a new resolution layer
+- Key design decision: economy mode ONLY affects Layer 3 auto-selection — Layer 0/1/2 (user intent) always wins
+- `💰` indicator in spawn acknowledgments keeps it transparent
+- Activation via session phrase, persistent config (`economyMode: true` in config.json), or CLI flag
+- Architecture trips shift from opus → sonnet; code tasks shift from sonnet → gpt-4.1/gpt-5-mini
+- Confidence: `low` — first implementation, not yet validated
+
+**Personal squad governance (proposals):**
+- Gap analysis: coordinator has no consult mode awareness despite full SDK implementation
+- Five gaps identified: Init Mode missing personal squad resolution, no consult mode detection, TEAM_ROOT has no personal-squad semantics, charter templates lack consult-mode patterns, no consult-mode skill
+- Proposed `CONSULT_MODE: true` as spawn prompt signal, `🧳 consult` in acknowledgments
+- Proposed new consult-mode skill (after governance approval — skill after governance, not before)
+
+**Governance workflow pattern:** When proposals touch squad.agent.md (governance territory), write to `decisions/inbox/` for Flight review. Don't directly edit squad.agent.md — Flight reviews governance changes.
+
+**Catalog audit finding:** `claude-sonnet-4.6`, `gpt-5.4`, `gpt-5.3-codex` appear in model-selection SKILL.md fallback chains but are absent from squad.agent.md's "Valid models" catalog. Documented in economy-mode governance proposal for Flight to address.
+
diff --git a/.squad/decisions/inbox/eecom-economy-mode.md b/.squad/decisions/inbox/eecom-economy-mode.md
new file mode 100644
index 000000000..d534aa5d6
--- /dev/null
+++ b/.squad/decisions/inbox/eecom-economy-mode.md
@@ -0,0 +1,37 @@
+# Economy Mode Design — #500
+
+**Date:** 2026-03-20  
+**Author:** EECOM  
+**Issue:** #500
+
+## Decision
+
+Economy mode is implemented as a modifier that shifts model selection at Layer 3 (task-aware auto) and Layer 4 (default fallback) only. Layers 0–2 (explicit user preferences) are never downgraded.
+
+## Model Map
+
+| Normal | Economy | Use case |
+|--------|---------|----------|
+| `claude-opus-4.6` | `claude-sonnet-4.5` | Architecture, review |
+| `claude-sonnet-4.6` | `gpt-4.1` | Code writing |
+| `claude-sonnet-4.5` | `gpt-4.1` | Code writing |
+| `claude-haiku-4.5` | `gpt-4.1` | Docs, planning, mechanical |
+
+## Activation
+
+1. **Persistent:** `"economyMode": true` in `.squad/config.json` (survives sessions)
+2. **Session:** `--economy` CLI flag (sets `SQUAD_ECONOMY_MODE=1` env var, current session only)
+3. **Toggle command:** `squad economy on|off` writes to config.json
+
+## Hierarchy Integration
+
+Economy mode is a Layer 3/4 modifier — it does NOT override explicit preferences (Layers 0–2). This is intentional: if a user said "always use opus", economy mode respects that choice.
+
+## Implementation Points
+
+- `ECONOMY_MODEL_MAP` + `applyEconomyMode()` in `packages/squad-sdk/src/config/models.ts`
+- `readEconomyMode()` + `writeEconomyMode()` in `packages/squad-sdk/src/config/models.ts`
+- `resolveModel()` in `config/models.ts` accepts `economyMode?: boolean` option; reads from config if not provided
+- `resolveModel()` in `agents/model-selector.ts` also supports `economyMode?: boolean`
+- `squad economy [on|off]` command in `packages/squad-cli/src/cli/commands/economy.ts`
+- `--economy` global flag in `cli-entry.ts`
diff --git a/.squad/decisions/inbox/procedures-economy-mode-governance.md b/.squad/decisions/inbox/procedures-economy-mode-governance.md
new file mode 100644
index 000000000..4561be940
--- /dev/null
+++ b/.squad/decisions/inbox/procedures-economy-mode-governance.md
@@ -0,0 +1,126 @@
+# Proposal: Economy Mode Integration in squad.agent.md
+
+**By:** Procedures (Prompt Engineer)  
+**Date:** 2026-03-22  
+**Issues:** #500  
+**Status:** DRAFT — for Flight review before merging to squad.agent.md
+
+---
+
+## Summary
+
+Economy mode is a new session/persistent modifier that shifts Layer 3 (Task-Aware Auto-Selection) to cost-optimized alternatives. This proposal documents the governance additions needed in `squad.agent.md`.
+
+**Note to Flight:** Procedures owns the skill design. Squad.agent.md is governance — Flight reviews before commit.
+
+---
+
+## 1. New Paragraph After Layer 0 (Per-Agent Model Selection section)
+
+Insert after the existing Layer 0 bullet points and before "**Layer 1 — Session Directive**":
+
+---
+
+**Economy Mode — Cost Modifier (Layer 3 override):** Economy mode shifts all Layer 3 auto-selection to cost-optimized alternatives. It does NOT override Layer 0 (persistent config), Layer 1 (explicit session directive), or Layer 2 (charter preference) — user intent always wins.
+
+- **Activation (session):** User says "use economy mode", "save costs", "go cheap" → activate for this session only.
+- **Activation (persistent):** User says "always use economy mode" OR `"economyMode": true` in `.squad/config.json` → persists across sessions.
+- **Deactivation:** "turn off economy mode" or remove `economyMode` from `config.json`.
+- **On session start:** Read `.squad/config.json`. If `economyMode: true`, activate economy mode before any spawns.
+
+---
+
+## 2. Economy Model Selection Table
+
+Add after Layer 3 normal table:
+
+---
+
+**Economy Mode Layer 3 Table** (active when economy mode is on):
+
+| Task Output | Normal Mode | Economy Mode |
+|-------------|-------------|--------------|
+| Writing code (implementation, refactoring, bug fixes) | `claude-sonnet-4.5` | `gpt-4.1` or `gpt-5-mini` |
+| Writing prompts or agent designs | `claude-sonnet-4.5` | `gpt-4.1` or `gpt-5-mini` |
+| Docs, planning, triage, changelogs, mechanical ops | `claude-haiku-4.5` | `gpt-4.1` or `gpt-5-mini` |
+| Architecture, code review, security audits | `claude-opus-4.5` | `claude-sonnet-4.5` |
+| Scribe / logger / mechanical file ops | `claude-haiku-4.5` | `gpt-4.1` |
+
+Prefer `gpt-4.1` over `gpt-5-mini` for structured output or tool use. Prefer `gpt-5-mini` for pure text generation.
+
+---
+
+## 3. Spawn Acknowledgment Convention
+
+Add to the spawn acknowledgment format guidance:
+
+---
+
+When economy mode is active, include `💰 economy` after the model name in spawn acknowledgments:
+
+```
+🔧 Fenster (gpt-4.1 · 💰 economy) — fixing auth bug
+📋 Scribe (gpt-4.1 · 💰 economy) — logging decision
+```
+
+This gives the user instant visibility that cost-optimized models are in use.
+
+---
+
+## 4. Valid Models Catalog Audit
+
+Current "Valid models" section lists:
+
+```
+Premium: claude-opus-4.6, claude-opus-4.6-fast, claude-opus-4.5
+Standard: claude-sonnet-4.5, claude-sonnet-4, gpt-5.2-codex, gpt-5.2, gpt-5.1-codex-max, gpt-5.1-codex, gpt-5.1, gpt-5, gemini-3-pro-preview
+Fast/Cheap: claude-haiku-4.5, gpt-5.1-codex-mini, gpt-5-mini, gpt-4.1
+```
+
+**Audit findings:**
+- `claude-opus-4.6` and `claude-opus-4.6-fast` are listed but not used in the Layer 3 table (table uses `claude-opus-4.5`). The Layer 3 table should reference `claude-opus-4.6` as the premium default for consistency with the catalog.
+- `claude-sonnet-4.6` appears in the model-selection SKILL.md but is absent from the valid models list in squad.agent.md. Add it under Standard.
+- Economy mode introduces `gpt-4.1` and `gpt-5-mini` as primary alternatives — both are already in the Fast/Cheap catalog. No additions needed.
+
+**Proposed updated catalog:**
+
+```
+Premium: claude-opus-4.6, claude-opus-4.6-fast, claude-opus-4.5
+Standard: claude-sonnet-4.6, claude-sonnet-4.5, claude-sonnet-4, gpt-5.4, gpt-5.3-codex, gpt-5.2-codex, gpt-5.2, gpt-5.1-codex-max, gpt-5.1-codex, gpt-5.1, gpt-5, gemini-3-pro-preview
+Fast/Cheap: claude-haiku-4.5, gpt-5.1-codex-mini, gpt-5-mini, gpt-4.1
+```
+
+(Added `claude-sonnet-4.6`, `gpt-5.4`, `gpt-5.3-codex` which appear in the model-selection SKILL.md fallback chains but are missing from squad.agent.md's catalog.)
+
+---
+
+## 5. Config Schema Addition
+
+Add `economyMode` to the config schema reference in squad.agent.md (wherever `defaultModel` is documented):
+
+```json
+{
+  "version": 1,
+  "defaultModel": "claude-sonnet-4.6",
+  "economyMode": true,
+  "agentModelOverrides": {
+    "fenster": "claude-sonnet-4.6"
+  }
+}
+```
+
+---
+
+## Rationale
+
+Economy mode solves a real user need: "I want all agents to run cheaper, but I don't want to set each one individually." It's a session-level modifier that works orthogonally to the existing hierarchy — no layer gets changed, only Layer 3's lookup table swaps. The `💰` indicator keeps it transparent.
+
+The skill (`economy-mode/SKILL.md`) covers the coordinator behavior in detail. This proposal is the governance side — ensuring squad.agent.md is the authoritative source for the feature.
+
+---
+
+## References
+
+- Skill: `.squad/skills/economy-mode/SKILL.md`
+- Issue: #500
+- Model selection skill: `.squad/skills/model-selection/SKILL.md`
diff --git a/.squad/decisions/inbox/procedures-personal-squad-governance.md b/.squad/decisions/inbox/procedures-personal-squad-governance.md
new file mode 100644
index 000000000..b46bb17de
--- /dev/null
+++ b/.squad/decisions/inbox/procedures-personal-squad-governance.md
@@ -0,0 +1,158 @@
+# Proposal: Personal Squad Governance Awareness in squad.agent.md
+
+**By:** Procedures (Prompt Engineer)  
+**Date:** 2026-03-22  
+**Issues:** #344  
+**Status:** DRAFT — for Flight review before merging to squad.agent.md
+
+---
+
+## Summary
+
+Squad has a consult mode (implemented, per `prd-consult-mode.md`) and personal squad semantics (via `resolveGlobalSquadPath()`), but `squad.agent.md` doesn't tell the coordinator how to reason about either. This proposal documents the gaps and the governance additions needed.
+
+---
+
+## Gap Analysis
+
+### Gap 1: Init Mode references `--global` without explaining personal squad resolution
+
+Current Init Mode says "run `squad init --global` for a personal squad" (implied by CLI docs) but squad.agent.md doesn't explain what a personal squad IS or how the coordinator should detect it.
+
+**What agents need to know:**
+- Personal squad = a squad at the global path (resolved via `resolveGlobalSquadPath()`)
+  - Linux/macOS: `~/.config/squad/.squad`
+  - macOS (alt): `~/Library/Application Support/squad/.squad`
+  - Windows: `%APPDATA%\squad\.squad`
+- If `.squad/config.json` contains `"consult": true`, the coordinator is working inside a consult session
+- `sourceSquad` in `config.json` points to the original personal squad (for Scribe extraction context)
+
+### Gap 2: No coordinator guidance for consult mode
+
+`squad.agent.md` mentions nothing about consult mode. The coordinator doesn't know:
+- How to recognize it's in a consult session
+- That writes go to the project `.squad/` (isolated copy) — NOT the personal squad
+- That Scribe's charter is patched with extraction instructions
+- That `.squad/extract/` is a staging area for generic learnings
+
+### Gap 3: TEAM_ROOT works, but personal squad semantics are absent
+
+The coordinator resolves `TEAM_ROOT` correctly (Worktree Awareness section), but:
+- No distinction between "project squad" vs "personal squad copy in consult mode"
+- No guidance on what to tell agents about their squad context when in consult mode
+
+### Gap 4: Charter templates have no personal-squad-aware patterns
+
+Agent charters have no concept of:
+- Consult mode restrictions (agents shouldn't commit to project, shouldn't pollute personal squad)
+- Extraction tagging (Scribe needs to flag decisions as generic vs project-specific)
+
+### Gap 5: No skill for consult-mode behavior
+
+There is no skill for consult-mode coordinator behavior, even though consult mode has distinct patterns (invisibility, extraction, isolation).
+
+---
+
+## Proposed squad.agent.md Additions
+
+### Addition 1: Consult Mode Detection (in Team Mode → On Session Start)
+
+After "resolve the team root" and before Issue Awareness, add:
+
+---
+
+**Consult Mode Detection:** After resolving team root, check `.squad/config.json` for `"consult": true`.
+
+- If `consult: true` → **Consult mode is active.** This is a personal squad consulting on a project.
+  - The `.squad/` directory is an isolated copy of the user's personal squad.
+  - `sourceSquad` in `config.json` contains the path to the original personal squad.
+  - Do NOT read or write to `sourceSquad` — it's out of scope. Only operate within TEAM_ROOT.
+  - Scribe's charter is already patched with extraction instructions — no coordinator action needed.
+  - Include `🧳 consult` in your session acknowledgment: `Squad v{version} (🧳 consult — {projectName})`
+  - Remind agents: decisions they make here are project-isolated until explicitly extracted.
+- If `consult: false` or absent → Normal mode. Team root is authoritative.
+
+---
+
+### Addition 2: Personal Squad Path Reference
+
+Add a new subsection under "Worktree Awareness":
+
+---
+
+**Personal Squad Paths:** The global squad path is resolved by `resolveGlobalSquadPath()`:
+
+| Platform | Path |
+|----------|------|
+| Linux | `~/.config/squad/.squad` |
+| macOS | `~/Library/Application Support/squad/.squad` |
+| Windows | `%APPDATA%\squad\.squad` |
+
+The coordinator should NEVER hard-code these paths. Use `squad --global` or `resolveGlobalSquadPath()` to resolve. Only relevant in consult mode (to understand the `sourceSquad` field) — the coordinator does NOT read the personal squad directly during a session.
+
+---
+
+### Addition 3: Consult Mode Spawn Guidance
+
+Add to the spawn template section:
+
+---
+
+**In consult mode:** Pass `CONSULT_MODE: true` and `PROJECT_NAME: {projectName}` in spawn prompts alongside `TEAM_ROOT`. This lets agents know:
+1. Their decisions will be reviewed for extraction — keep project-specific and generic reasoning separate
+2. They should NOT reference personal squad paths or personal squad agent names
+3. Scribe will classify their decisions — agents should write clear, extractable decision rationale
+
+---
+
+### Addition 4: Consult Mode Acknowledgment Format
+
+Add to spawn acknowledgment conventions:
+
+```
+🧳 consult mode active — Fenster (claude-sonnet-4.5) — refactoring auth module
+     ↳ decisions staged in .squad/extract/ for review before extraction
+```
+
+---
+
+## Proposed New Skill
+
+**Skill needed:** `.squad/skills/consult-mode/SKILL.md`
+
+Should cover:
+- Detecting consult mode from config.json
+- Coordinator behavior changes (CONSULT_MODE in spawn prompts)
+- Scribe extraction workflow (already documented in prd-consult-mode.md — condense into skill)
+- Acknowledgment format conventions
+- STOP: extraction is always user-driven via `squad extract` — coordinator never auto-extracts
+
+This skill should be authored after this governance proposal is approved, to avoid the skill getting ahead of the governance.
+
+---
+
+## Charter Template Additions
+
+All agent charter templates should include a note in "How I Work":
+
+```markdown
+**Consult Mode Awareness:** If `CONSULT_MODE: true` is in my spawn prompt, I'm working on a project outside my home squad. My decisions here are project-isolated. Write extractable rationale so Scribe can classify them for `squad extract` review.
+```
+
+This should be added to `.squad/templates/charter.md` (if it exists) and `.squad/agents/scribe/charter.md` (Scribe already has extraction logic, but clarifying the classification responsibility is valuable).
+
+---
+
+## Rationale
+
+Consult mode is fully implemented at the SDK level (`prd-consult-mode.md`, `squad consult` command) but the coordinator has no awareness of it. The result: agents running in a consult session have no context that they're in a temporary, isolated copy of a personal squad. They might make decisions as if they're permanent, or reference the project in ways that pollute the personal squad on extraction.
+
+These governance additions close the loop between the implementation (CLI + SDK) and the runtime behavior (coordinator + agents).
+
+---
+
+## References
+
+- Consult mode PRD: `.squad/identity/prd-consult-mode.md`
+- Issue: #344
+- Flight ambient personal squad note: `.squad/decisions/inbox/flight-ambient-personal-squad.md`
diff --git a/.squad/skills/economy-mode/SKILL.md b/.squad/skills/economy-mode/SKILL.md
new file mode 100644
index 000000000..696e778c4
--- /dev/null
+++ b/.squad/skills/economy-mode/SKILL.md
@@ -0,0 +1,114 @@
+---
+name: "economy-mode"
+description: "Shifts Layer 3 model selection to cost-optimized alternatives when economy mode is active."
+domain: "model-selection"
+confidence: "low"
+source: "manual"
+---
+
+## SCOPE
+
+✅ THIS SKILL PRODUCES:
+- A modified Layer 3 model selection table applied when economy mode is active
+- `economyMode: true` written to `.squad/config.json` when activated persistently
+- Spawn acknowledgments with `💰` indicator when economy mode is active
+
+❌ THIS SKILL DOES NOT PRODUCE:
+- Code, tests, or documentation
+- Cost reports or billing artifacts
+- Changes to Layer 0, Layer 1, or Layer 2 resolution (user intent always wins)
+
+## Context
+
+Economy mode shifts Layer 3 (Task-Aware Auto-Selection) to lower-cost alternatives. It does NOT override persistent config (`defaultModel`, `agentModelOverrides`) or per-agent charter preferences — those represent explicit user intent and always take priority.
+
+Use this skill when the user wants to reduce costs across an entire session or permanently, without manually specifying models for each agent.
+
+## Activation Methods
+
+| Method | How |
+|--------|-----|
+| Session phrase | "use economy mode", "save costs", "go cheap", "reduce costs" |
+| Persistent config | `"economyMode": true` in `.squad/config.json` |
+| CLI flag | `squad --economy` |
+
+**Deactivation:** "turn off economy mode", "disable economy mode", or remove `economyMode` from `config.json`.
+
+## Economy Model Selection Table
+
+When economy mode is **active**, Layer 3 auto-selection uses this table instead of the normal defaults:
+
+| Task Output | Normal Mode | Economy Mode |
+|-------------|-------------|--------------|
+| Writing code (implementation, refactoring, bug fixes) | `claude-sonnet-4.5` | `gpt-4.1` or `gpt-5-mini` |
+| Writing prompts or agent designs | `claude-sonnet-4.5` | `gpt-4.1` or `gpt-5-mini` |
+| Docs, planning, triage, changelogs, mechanical ops | `claude-haiku-4.5` | `gpt-4.1` or `gpt-5-mini` |
+| Architecture, code review, security audits | `claude-opus-4.5` | `claude-sonnet-4.5` |
+| Scribe / logger / mechanical file ops | `claude-haiku-4.5` | `gpt-4.1` |
+
+**Prefer `gpt-4.1` over `gpt-5-mini`** when the task involves structured output or agentic tool use. Prefer `gpt-5-mini` for pure text generation tasks where latency matters.
+
+## AGENT WORKFLOW
+
+### On Session Start
+
+1. READ `.squad/config.json`
+2. CHECK for `economyMode: true` — if present, activate economy mode for the session
+3. STORE economy mode state in session context
+
+### On User Phrase Trigger
+
+**Session-only (no config change):** "use economy mode", "save costs", "go cheap"
+
+1. SET economy mode active for this session
+2. ACKNOWLEDGE: `✅ Economy mode active — using cost-optimized models this session. (Layer 0 and Layer 2 preferences still apply)`
+
+**Persistent:** "always use economy mode", "save economy mode"
+
+1. WRITE `economyMode: true` to `.squad/config.json` (merge, don't overwrite other fields)
+2. ACKNOWLEDGE: `✅ Economy mode saved — cost-optimized models will be used until disabled.`
+
+### On Every Agent Spawn (Economy Mode Active)
+
+1. CHECK Layer 0a/0b first (agentModelOverrides, defaultModel) — if set, use that. Economy mode does NOT override Layer 0.
+2. CHECK Layer 1 (session directive for a specific model) — if set, use that. Economy mode does NOT override explicit session directives.
+3. CHECK Layer 2 (charter preference) — if set, use that. Economy mode does NOT override charter preferences.
+4. APPLY economy table at Layer 3 instead of normal table.
+5. INCLUDE `💰` in spawn acknowledgment: `🔧 {Name} ({model} · 💰 economy) — {task}`
+
+### On Deactivation
+
+**Trigger phrases:** "turn off economy mode", "disable economy mode", "use normal models"
+
+1. REMOVE `economyMode` from `.squad/config.json` (if it was persisted)
+2. CLEAR session economy mode state
+3. ACKNOWLEDGE: `✅ Economy mode disabled — returning to standard model selection.`
+
+### STOP
+
+After updating economy mode state and including the `💰` indicator in spawn acknowledgments, this skill is done. Do NOT:
+- Change Layer 0, Layer 1, or Layer 2 model choices
+- Override charter-specified models
+- Generate cost reports or comparisons
+- Fall back to premium models via economy mode (economy mode never bumps UP)
+
+## Config Schema
+
+`.squad/config.json` economy-related fields:
+
+```json
+{
+  "version": 1,
+  "economyMode": true
+}
+```
+
+- `economyMode` — when `true`, Layer 3 uses the economy table. Optional; absent = economy mode off.
+- Combines with `defaultModel` and `agentModelOverrides` — Layer 0 always wins.
+
+## Anti-Patterns
+
+- **Don't override Layer 0 in economy mode.** If the user set `defaultModel: "claude-opus-4.6"`, they want quality. Economy mode only affects Layer 3 auto-selection.
+- **Don't silently apply economy mode.** Always acknowledge when activated or deactivated.
+- **Don't treat economy mode as permanent by default.** Session phrases activate session-only; only "always" or `config.json` persist it.
+- **Don't bump premium tasks down too far.** Architecture and security reviews shift from opus to sonnet in economy mode — they do NOT go to fast/cheap models.
diff --git a/packages/squad-cli/src/cli-entry.ts b/packages/squad-cli/src/cli-entry.ts
index da8ce8b56..6a121f853 100644
--- a/packages/squad-cli/src/cli-entry.ts
+++ b/packages/squad-cli/src/cli-entry.ts
@@ -132,6 +132,11 @@ async function checkNodeSqlite(): Promise<void> {
 async function main(): Promise<void> {
   const args = process.argv.slice(2);
   const hasGlobal = args.includes('--global');
+  // --economy activates economy mode for this session (sets env var for spawner)
+  const hasEconomy = args.includes('--economy');
+  if (hasEconomy) {
+    process.env['SQUAD_ECONOMY_MODE'] = '1';
+  }
   const rawCmd = args[0];
   const cmd = rawCmd?.trim() || '';
 
@@ -225,12 +230,15 @@ async function main(): Promise<void> {
     console.log(`                    upstream remove <name>`);
     console.log(`                    upstream list`);
     console.log(`                    upstream sync [name]`);
+    console.log(`  ${BOLD}economy${RESET}    Toggle economy mode (cost-conscious model selection)`);
+    console.log(`             Usage: economy [on|off]`);
 
     console.log(`  ${BOLD}help${RESET}       Show this help message`);
     console.log(`\nFlags:`);
     console.log(`  ${BOLD}--version, -v${RESET}  Print version`);
     console.log(`  ${BOLD}--help, -h${RESET}     Show help`);
     console.log(`  ${BOLD}--global${RESET}       Use personal (global) squad path (for init, upgrade)`);
+    console.log(`  ${BOLD}--economy${RESET}      Activate economy mode for this session (cheaper models)`);
     console.log(`\nInstallation:`);
     console.log(`  npm install --save-dev @bradygaster/squad-cli`);
     console.log(`\nInsider channel:`);
@@ -605,6 +613,12 @@ async function main(): Promise<void> {
     return;
   }
 
+  if (cmd === 'economy') {
+    const { runEconomy } = await import('./cli/commands/economy.js');
+    await runEconomy(process.cwd(), args.slice(1));
+    return;
+  }
+
   // Unknown command
   fatal(`Unknown command: ${cmd}\n       Run 'squad doctor' to check your setup, or 'squad help' for usage information.`);
 }
diff --git a/packages/squad-cli/src/cli/commands/economy.ts b/packages/squad-cli/src/cli/commands/economy.ts
new file mode 100644
index 000000000..3043d03a2
--- /dev/null
+++ b/packages/squad-cli/src/cli/commands/economy.ts
@@ -0,0 +1,68 @@
+/**
+ * Economy mode command — toggle cost-conscious model selection.
+ *
+ * Usage:
+ *   squad economy on    — enable economy mode (persisted to config.json)
+ *   squad economy off   — disable economy mode
+ *   squad economy       — show current status
+ */
+
+import { join } from 'node:path';
+import { existsSync, readFileSync } from 'node:fs';
+import { writeEconomyMode, readEconomyMode } from '@bradygaster/squad-sdk/config';
+import { fatal } from '../core/errors.js';
+import { BOLD, RESET, GREEN, DIM } from '../core/output.js';
+
+function resolveSquadDir(cwd: string): string | null {
+  // Walk up to find .squad/
+  let dir = cwd;
+  for (let i = 0; i < 10; i++) {
+    const candidate = join(dir, '.squad');
+    if (existsSync(candidate)) {
+      return candidate;
+    }
+    const parent = join(dir, '..');
+    if (parent === dir) break;
+    dir = parent;
+  }
+  return null;
+}
+
+export async function runEconomy(cwd: string, subArgs: string[]): Promise<void> {
+  const squadDir = resolveSquadDir(cwd);
+  if (!squadDir) {
+    fatal('No squad found. Run "squad init" first.');
+    return;
+  }
+
+  const sub = subArgs[0]?.toLowerCase();
+
+  if (sub === 'on') {
+    writeEconomyMode(squadDir, true);
+    console.log(`${GREEN}✓${RESET} Economy mode ${BOLD}enabled${RESET} — cheaper models will be used for auto-selection.`);
+    console.log(`  Saved to: ${DIM}${join(squadDir, 'config.json')}${RESET}`);
+    return;
+  }
+
+  if (sub === 'off') {
+    writeEconomyMode(squadDir, false);
+    console.log(`${GREEN}✓${RESET} Economy mode ${BOLD}disabled${RESET} — returning to standard model selection.`);
+    console.log(`  Saved to: ${DIM}${join(squadDir, 'config.json')}${RESET}`);
+    return;
+  }
+
+  // Status display
+  const enabled = readEconomyMode(squadDir);
+  console.log(`\n${BOLD}Economy Mode${RESET}\n`);
+  console.log(`  Status: ${enabled ? `${GREEN}enabled${RESET}` : `${DIM}disabled${RESET}`}`);
+  console.log(`  Config: ${DIM}${join(squadDir, 'config.json')}${RESET}\n`);
+  if (enabled) {
+    console.log(`  When active, auto-selected models are downgraded:`);
+    console.log(`    ${DIM}claude-opus-4.6   → claude-sonnet-4.5  (architecture/review)${RESET}`);
+    console.log(`    ${DIM}claude-sonnet-4.6 → gpt-4.1            (code writing)${RESET}`);
+    console.log(`    ${DIM}claude-haiku-4.5  → gpt-4.1            (docs/mechanical)${RESET}`);
+    console.log(`  Explicit overrides (config.json, charter) are never changed.\n`);
+  } else {
+    console.log(`  Usage: squad economy on | off\n`);
+  }
+}
diff --git a/packages/squad-sdk/src/agents/model-selector.ts b/packages/squad-sdk/src/agents/model-selector.ts
index 2e2eee305..0fa0bfacb 100644
--- a/packages/squad-sdk/src/agents/model-selector.ts
+++ b/packages/squad-sdk/src/agents/model-selector.ts
@@ -3,6 +3,7 @@
  */
 
 import { MODELS } from '../runtime/constants.js';
+import { applyEconomyMode } from '../config/models.js';
 import type { EventBus } from '../runtime/event-bus.js';
 
 /**
@@ -32,6 +33,8 @@ export interface ModelResolutionOptions {
   taskType: TaskType;
   /** Agent role (for context) */
   agentRole?: string;
+  /** When true, apply economy mode substitution at Layer 3/4 */
+  economyMode?: boolean;
 }
 
 /**
@@ -55,9 +58,9 @@ export interface ResolvedModel {
  * @returns Resolved model with tier and fallback chain
  */
 export function resolveModel(options: ModelResolutionOptions): ResolvedModel {
-  const { userOverride, charterPreference, taskType } = options;
+  const { userOverride, charterPreference, taskType, economyMode } = options;
 
-  // Layer 1: User Override
+  // Layer 1: User Override (explicit — economy does not apply)
   if (userOverride && userOverride.trim().length > 0) {
     const tier = inferTierFromModel(userOverride);
     return {
@@ -68,7 +71,7 @@ export function resolveModel(options: ModelResolutionOptions): ResolvedModel {
     };
   }
 
-  // Layer 2: Charter Preference
+  // Layer 2: Charter Preference (explicit — economy does not apply)
   if (charterPreference && charterPreference.trim().length > 0 && charterPreference !== 'auto') {
     const tier = inferTierFromModel(charterPreference);
     return {
@@ -79,66 +82,70 @@ export function resolveModel(options: ModelResolutionOptions): ResolvedModel {
     };
   }
 
-  // Layer 3: Task-Aware Auto-Selection
-  const autoSelected = selectModelForTask(taskType);
+  // Layer 3: Task-Aware Auto-Selection (economy mode applies)
+  const autoSelected = selectModelForTask(taskType, economyMode);
   if (autoSelected) {
     return autoSelected;
   }
 
-  // Layer 4: Default
+  // Layer 4: Default (economy mode applies)
+  const defaultModel = economyMode
+    ? applyEconomyMode(MODELS.SELECTOR_DEFAULT)
+    : MODELS.SELECTOR_DEFAULT;
+  const defaultTier = inferTierFromModel(defaultModel);
   return {
-    model: MODELS.SELECTOR_DEFAULT,
-    tier: MODELS.SELECTOR_DEFAULT_TIER,
+    model: defaultModel,
+    tier: defaultTier,
     source: 'default',
-    fallbackChain: [...MODELS.FALLBACK_CHAINS[MODELS.SELECTOR_DEFAULT_TIER]],
+    fallbackChain: [...MODELS.FALLBACK_CHAINS[defaultTier]],
   };
 }
 
 /**
- * Select model based on task type.
+ * Select model based on task type, with optional economy mode substitution.
  * 
  * @param taskType - Type of task being performed
+ * @param economyMode - When true, downgrade model to cheaper alternative
  * @returns Resolved model or undefined if no match
  */
-function selectModelForTask(taskType: TaskType): ResolvedModel | undefined {
+function selectModelForTask(taskType: TaskType, economyMode?: boolean): ResolvedModel | undefined {
+  let model: string | undefined;
+  let tier: ModelTier | undefined;
+
   switch (taskType) {
     case 'code':
-      return {
-        model: 'claude-sonnet-4.6',
-        tier: 'standard',
-        source: 'task-auto',
-        fallbackChain: [...MODELS.FALLBACK_CHAINS.standard],
-      };
-    
+      model = 'claude-sonnet-4.6';
+      tier = 'standard';
+      break;
     case 'prompt':
-      return {
-        model: 'claude-sonnet-4.6',
-        tier: 'standard',
-        source: 'task-auto',
-        fallbackChain: [...MODELS.FALLBACK_CHAINS.standard],
-      };
-    
+      model = 'claude-sonnet-4.6';
+      tier = 'standard';
+      break;
     case 'visual':
-      return {
-        model: 'claude-opus-4.6',
-        tier: 'premium',
-        source: 'task-auto',
-        fallbackChain: [...MODELS.FALLBACK_CHAINS.premium],
-      };
-    
+      model = 'claude-opus-4.6';
+      tier = 'premium';
+      break;
     case 'docs':
     case 'planning':
     case 'mechanical':
-      return {
-        model: 'claude-haiku-4.5',
-        tier: 'fast',
-        source: 'task-auto',
-        fallbackChain: [...MODELS.FALLBACK_CHAINS.fast],
-      };
-    
+      model = 'claude-haiku-4.5';
+      tier = 'fast';
+      break;
     default:
       return undefined;
   }
+
+  if (economyMode) {
+    model = applyEconomyMode(model);
+    tier = inferTierFromModel(model);
+  }
+
+  return {
+    model,
+    tier,
+    source: 'task-auto',
+    fallbackChain: [...MODELS.FALLBACK_CHAINS[tier]],
+  };
 }
 
 export function inferTierFromModel(model: string): ModelTier {
diff --git a/packages/squad-sdk/src/config/models.ts b/packages/squad-sdk/src/config/models.ts
index 370040bc6..cac32e4a8 100644
--- a/packages/squad-sdk/src/config/models.ts
+++ b/packages/squad-sdk/src/config/models.ts
@@ -511,12 +511,93 @@ export function estimateCost(model: string, inputTokens: number, outputTokens: n
 // Persistent Model Preference (Layer 0)
 // ============================================================================
 
+/**
+ * Economy mode model map: normal model → cheaper alternative.
+ *
+ * Applied at Layer 3 (task-aware auto) and Layer 4 (default) when
+ * economy mode is active. Layers 0–2 (explicit preferences) are
+ * never substituted — the user's explicit choice always wins.
+ *
+ * Table source: issue #500
+ */
+export const ECONOMY_MODEL_MAP: Record<string, string> = {
+  // Premium → standard downgrade (architecture/review tasks)
+  'claude-opus-4.6':      'claude-sonnet-4.5',
+  'claude-opus-4.6-fast': 'claude-sonnet-4.5',
+  'claude-opus-4.5':      'claude-sonnet-4.5',
+  // Standard → fast downgrade (code writing, docs, planning, triage)
+  'claude-sonnet-4.6':    'gpt-4.1',
+  'claude-sonnet-4.5':    'gpt-4.1',
+  // Fast → cheapest fast (scribe/mechanical, docs)
+  'claude-haiku-4.5':     'gpt-4.1',
+};
+
+/**
+ * Applies economy mode substitution to a model ID.
+ * Returns the cheaper economy alternative, or the original if no mapping exists.
+ */
+export function applyEconomyMode(model: string): string {
+  return ECONOMY_MODEL_MAP[model] ?? model;
+}
+
 /**
  * Shape of model preference fields within `.squad/config.json`.
  */
 export interface ModelPreferenceConfig {
   defaultModel?: string;
   agentModelOverrides?: Record<string, string>;
+  economyMode?: boolean;
+}
+
+/**
+ * Reads the economy mode setting from `.squad/config.json`.
+ *
+ * @param squadDir - Path to the `.squad/` directory
+ * @returns True if economyMode is enabled, false otherwise
+ */
+export function readEconomyMode(squadDir: string): boolean {
+  const configPath = join(squadDir, 'config.json');
+  if (!existsSync(configPath)) {
+    return false;
+  }
+  try {
+    const raw = readFileSync(configPath, 'utf-8');
+    const parsed = JSON.parse(raw);
+    return parsed !== null &&
+      typeof parsed === 'object' &&
+      parsed.economyMode === true;
+  } catch {
+    return false;
+  }
+}
+
+/**
+ * Writes the economy mode setting to `.squad/config.json`.
+ * Merges with existing config — does not overwrite other fields.
+ *
+ * @param squadDir - Path to the `.squad/` directory
+ * @param enabled - Whether economy mode should be enabled
+ */
+export function writeEconomyMode(squadDir: string, enabled: boolean): void {
+  const configPath = join(squadDir, 'config.json');
+  let config: Record<string, unknown> = {};
+  if (existsSync(configPath)) {
+    try {
+      config = JSON.parse(readFileSync(configPath, 'utf-8'));
+    } catch {
+      config = { version: 1 };
+    }
+  } else {
+    config = { version: 1 };
+  }
+
+  if (enabled) {
+    config.economyMode = true;
+  } else {
+    delete config.economyMode;
+  }
+
+  writeFileSync(configPath, JSON.stringify(config, null, 2) + '\n', 'utf-8');
 }
 
 /**
@@ -652,6 +733,10 @@ export function writeAgentModelOverrides(
  *
  * Per-agent overrides from config.json take priority over the global defaultModel.
  *
+ * Economy mode modifier: when active (via economyMode option or config.json),
+ * shifts model selection at Layer 3 and Layer 4 to cheaper alternatives per
+ * ECONOMY_MODEL_MAP. Layers 0–2 (explicit user preferences) are never overridden.
+ *
  * @param options - Resolution inputs
  * @returns Resolved model ID
  */
@@ -661,10 +746,12 @@ export function resolveModel(options: {
   sessionDirective?: string | null;
   charterPreference?: string | null;
   taskModel?: string | null;
+  /** When true, apply economy mode substitution at Layer 3/4. Overrides config. */
+  economyMode?: boolean;
 }): string {
   const { agentName, squadDir, sessionDirective, charterPreference, taskModel } = options;
 
-  // Layer 0a: Per-agent persistent override
+  // Layer 0a: Per-agent persistent override (explicit — economy does not apply)
   if (squadDir && agentName) {
     const agentOverrides = readAgentModelOverrides(squadDir);
     if (agentOverrides[agentName]) {
@@ -672,7 +759,7 @@ export function resolveModel(options: {
     }
   }
 
-  // Layer 0b: Global persistent config
+  // Layer 0b: Global persistent config (explicit — economy does not apply)
   if (squadDir) {
     const persistedModel = readModelPreference(squadDir);
     if (persistedModel) {
@@ -680,21 +767,28 @@ export function resolveModel(options: {
     }
   }
 
-  // Layer 1: Session-wide user directive
+  // Layer 1: Session-wide user directive (explicit — economy does not apply)
   if (sessionDirective) {
     return sessionDirective;
   }
 
-  // Layer 2: Charter preference
+  // Layer 2: Charter preference (explicit — economy does not apply)
   if (charterPreference) {
     return charterPreference;
   }
 
-  // Layer 3: Task-aware auto-selection
+  // Determine if economy mode is active (option takes precedence over config)
+  const isEconomy =
+    options.economyMode !== undefined
+      ? options.economyMode
+      : (squadDir ? readEconomyMode(squadDir) : false);
+
+  // Layer 3: Task-aware auto-selection (economy mode applies)
   if (taskModel) {
-    return taskModel;
+    return isEconomy ? applyEconomyMode(taskModel) : taskModel;
   }
 
-  // Layer 4: Default
-  return 'claude-haiku-4.5';
+  // Layer 4: Default (economy mode applies)
+  const defaultModel = 'claude-haiku-4.5';
+  return isEconomy ? applyEconomyMode(defaultModel) : defaultModel;
 }
diff --git a/test/economy-mode.test.ts b/test/economy-mode.test.ts
new file mode 100644
index 000000000..9835b4816
--- /dev/null
+++ b/test/economy-mode.test.ts
@@ -0,0 +1,291 @@
+/**
+ * Tests for economy mode model selection (issue #500).
+ *
+ * Validates that when economy mode is active:
+ *   - Layer 3 (task-aware) and Layer 4 (default) models are downgraded
+ *   - Layer 0–2 (explicit preferences) are never overridden
+ *   - config.json read/write round-trips correctly
+ */
+
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import { mkdtempSync, writeFileSync, readFileSync, rmSync } from 'fs';
+import { join } from 'path';
+import { tmpdir } from 'os';
+import {
+  resolveModel,
+  readEconomyMode,
+  writeEconomyMode,
+  applyEconomyMode,
+  ECONOMY_MODEL_MAP,
+} from '@bradygaster/squad-sdk/config';
+import {
+  resolveModel as sdkResolveModel,
+} from '@bradygaster/squad-sdk/agents';
+
+let squadDir: string;
+
+beforeEach(() => {
+  squadDir = mkdtempSync(join(tmpdir(), 'squad-economy-'));
+});
+
+afterEach(() => {
+  rmSync(squadDir, { recursive: true, force: true });
+});
+
+// ============================================================================
+// ECONOMY_MODEL_MAP + applyEconomyMode
+// ============================================================================
+
+describe('ECONOMY_MODEL_MAP', () => {
+  it('maps premium models to standard', () => {
+    expect(ECONOMY_MODEL_MAP['claude-opus-4.6']).toBe('claude-sonnet-4.5');
+    expect(ECONOMY_MODEL_MAP['claude-opus-4.6-fast']).toBe('claude-sonnet-4.5');
+    expect(ECONOMY_MODEL_MAP['claude-opus-4.5']).toBe('claude-sonnet-4.5');
+  });
+
+  it('maps standard sonnet models to fast', () => {
+    expect(ECONOMY_MODEL_MAP['claude-sonnet-4.6']).toBe('gpt-4.1');
+    expect(ECONOMY_MODEL_MAP['claude-sonnet-4.5']).toBe('gpt-4.1');
+  });
+
+  it('maps haiku to cheapest fast', () => {
+    expect(ECONOMY_MODEL_MAP['claude-haiku-4.5']).toBe('gpt-4.1');
+  });
+});
+
+describe('applyEconomyMode', () => {
+  it('returns economy model for known models', () => {
+    expect(applyEconomyMode('claude-opus-4.6')).toBe('claude-sonnet-4.5');
+    expect(applyEconomyMode('claude-sonnet-4.6')).toBe('gpt-4.1');
+    expect(applyEconomyMode('claude-haiku-4.5')).toBe('gpt-4.1');
+  });
+
+  it('returns original model when no economy mapping exists', () => {
+    expect(applyEconomyMode('gpt-4.1')).toBe('gpt-4.1');
+    expect(applyEconomyMode('gpt-5-mini')).toBe('gpt-5-mini');
+    expect(applyEconomyMode('unknown-model-xyz')).toBe('unknown-model-xyz');
+  });
+});
+
+// ============================================================================
+// readEconomyMode / writeEconomyMode
+// ============================================================================
+
+describe('readEconomyMode', () => {
+  it('returns false when config.json does not exist', () => {
+    expect(readEconomyMode(squadDir)).toBe(false);
+  });
+
+  it('returns false when economyMode field is absent', () => {
+    writeFileSync(join(squadDir, 'config.json'), JSON.stringify({ version: 1 }));
+    expect(readEconomyMode(squadDir)).toBe(false);
+  });
+
+  it('returns false when economyMode is false', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({ version: 1, economyMode: false })
+    );
+    expect(readEconomyMode(squadDir)).toBe(false);
+  });
+
+  it('returns true when economyMode is true', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({ version: 1, economyMode: true })
+    );
+    expect(readEconomyMode(squadDir)).toBe(true);
+  });
+
+  it('returns false on malformed JSON', () => {
+    writeFileSync(join(squadDir, 'config.json'), '{ bad json');
+    expect(readEconomyMode(squadDir)).toBe(false);
+  });
+});
+
+describe('writeEconomyMode', () => {
+  it('creates config.json with economyMode: true', () => {
+    writeEconomyMode(squadDir, true);
+    const raw = JSON.parse(readFileSync(join(squadDir, 'config.json'), 'utf-8'));
+    expect(raw.economyMode).toBe(true);
+    expect(raw.version).toBe(1);
+  });
+
+  it('removes economyMode field when set to false', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({ version: 1, economyMode: true })
+    );
+    writeEconomyMode(squadDir, false);
+    const raw = JSON.parse(readFileSync(join(squadDir, 'config.json'), 'utf-8'));
+    expect(raw).not.toHaveProperty('economyMode');
+  });
+
+  it('merges with existing config without clobbering other fields', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({ version: 1, defaultModel: 'claude-opus-4.6' })
+    );
+    writeEconomyMode(squadDir, true);
+    const raw = JSON.parse(readFileSync(join(squadDir, 'config.json'), 'utf-8'));
+    expect(raw.defaultModel).toBe('claude-opus-4.6');
+    expect(raw.economyMode).toBe(true);
+  });
+
+  it('round-trips: write on → read true', () => {
+    writeEconomyMode(squadDir, true);
+    expect(readEconomyMode(squadDir)).toBe(true);
+  });
+
+  it('round-trips: write off → read false', () => {
+    writeEconomyMode(squadDir, true);
+    writeEconomyMode(squadDir, false);
+    expect(readEconomyMode(squadDir)).toBe(false);
+  });
+});
+
+// ============================================================================
+// resolveModel — economy mode option
+// ============================================================================
+
+describe('resolveModel economy mode (option)', () => {
+  it('Layer 4 default: uses gpt-4.1 instead of haiku when economyMode: true', () => {
+    expect(resolveModel({ economyMode: true })).toBe('gpt-4.1');
+  });
+
+  it('Layer 4 default: uses haiku when economyMode: false', () => {
+    expect(resolveModel({ economyMode: false })).toBe('claude-haiku-4.5');
+  });
+
+  it('Layer 3 code task: uses gpt-4.1 instead of sonnet when economyMode: true', () => {
+    expect(resolveModel({ taskModel: 'claude-sonnet-4.6', economyMode: true })).toBe('gpt-4.1');
+  });
+
+  it('Layer 3 architecture task: uses sonnet instead of opus when economyMode: true', () => {
+    expect(resolveModel({ taskModel: 'claude-opus-4.6', economyMode: true })).toBe('claude-sonnet-4.5');
+  });
+
+  it('Layer 3 docs task: uses gpt-4.1 instead of haiku when economyMode: true', () => {
+    expect(resolveModel({ taskModel: 'claude-haiku-4.5', economyMode: true })).toBe('gpt-4.1');
+  });
+
+  it('Layer 2 charter preference: NOT overridden by economy mode', () => {
+    expect(
+      resolveModel({ charterPreference: 'claude-opus-4.6', economyMode: true })
+    ).toBe('claude-opus-4.6');
+  });
+
+  it('Layer 1 session directive: NOT overridden by economy mode', () => {
+    expect(
+      resolveModel({ sessionDirective: 'claude-opus-4.6', economyMode: true })
+    ).toBe('claude-opus-4.6');
+  });
+
+  it('Layer 0b global config: NOT overridden by economy mode', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({ version: 1, defaultModel: 'claude-opus-4.6' })
+    );
+    expect(
+      resolveModel({ squadDir, taskModel: 'claude-sonnet-4.6', economyMode: true })
+    ).toBe('claude-opus-4.6');
+  });
+
+  it('Layer 0a per-agent override: NOT overridden by economy mode', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({
+        version: 1,
+        agentModelOverrides: { eecom: 'claude-opus-4.6' },
+      })
+    );
+    expect(
+      resolveModel({ agentName: 'eecom', squadDir, taskModel: 'claude-haiku-4.5', economyMode: true })
+    ).toBe('claude-opus-4.6');
+  });
+});
+
+// ============================================================================
+// resolveModel — economy mode from config.json
+// ============================================================================
+
+describe('resolveModel economy mode (from config)', () => {
+  it('uses economy model when economyMode: true in config', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({ version: 1, economyMode: true })
+    );
+    expect(resolveModel({ squadDir, taskModel: 'claude-sonnet-4.6' })).toBe('gpt-4.1');
+  });
+
+  it('uses normal model when economyMode absent from config', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({ version: 1 })
+    );
+    expect(resolveModel({ squadDir, taskModel: 'claude-sonnet-4.6' })).toBe('claude-sonnet-4.6');
+  });
+
+  it('explicit economyMode option overrides config setting', () => {
+    writeFileSync(
+      join(squadDir, 'config.json'),
+      JSON.stringify({ version: 1, economyMode: false })
+    );
+    // Option says true, config says false → option wins
+    expect(
+      resolveModel({ squadDir, taskModel: 'claude-sonnet-4.6', economyMode: true })
+    ).toBe('gpt-4.1');
+  });
+});
+
+// ============================================================================
+// SDK model-selector resolveModel economy mode
+// ============================================================================
+
+describe('SDK resolveModel (agents) economy mode', () => {
+  it('code task → gpt-4.1 when economyMode: true', () => {
+    const result = sdkResolveModel({ taskType: 'code', economyMode: true });
+    expect(result.model).toBe('gpt-4.1');
+    expect(result.source).toBe('task-auto');
+  });
+
+  it('docs task → gpt-4.1 when economyMode: true', () => {
+    const result = sdkResolveModel({ taskType: 'docs', economyMode: true });
+    expect(result.model).toBe('gpt-4.1');
+  });
+
+  it('mechanical task → gpt-4.1 when economyMode: true', () => {
+    const result = sdkResolveModel({ taskType: 'mechanical', economyMode: true });
+    expect(result.model).toBe('gpt-4.1');
+  });
+
+  it('visual task → claude-sonnet-4.5 when economyMode: true', () => {
+    const result = sdkResolveModel({ taskType: 'visual', economyMode: true });
+    expect(result.model).toBe('claude-sonnet-4.5');
+  });
+
+  it('code task → claude-sonnet-4.6 when economyMode: false', () => {
+    const result = sdkResolveModel({ taskType: 'code', economyMode: false });
+    expect(result.model).toBe('claude-sonnet-4.6');
+  });
+
+  it('user override NOT affected by economy mode', () => {
+    const result = sdkResolveModel({
+      taskType: 'code',
+      userOverride: 'claude-opus-4.6',
+      economyMode: true,
+    });
+    expect(result.model).toBe('claude-opus-4.6');
+    expect(result.source).toBe('user-override');
+  });
+
+  it('charter preference NOT affected by economy mode', () => {
+    const result = sdkResolveModel({
+      taskType: 'code',
+      charterPreference: 'claude-opus-4.6',
+      economyMode: true,
+    });
+    expect(result.model).toBe('claude-opus-4.6');
+    expect(result.source).toBe('charter');
+  });
+});