diff --git a/_bridges/README.md b/_bridges/README.md
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+# `_bridges/` — Cross-tool bridge templates
+
+Tool-agnostic coding-rules templates, rendered into any project via `_bridges/emit.sh`. Placeholders: `{{PROJECT_NAME}}`, `{{PROJECT_DESCRIPTION}}`, `{{YEAR}}`, `{{MONTH}}`, `{{DATE}}`.
+
+| Template | Output path |
+|---|---|
+| `cursorrules.tmpl` | `.cursorrules` |
+| `agents-md.tmpl` | `AGENTS.md` |
+| `copilot.tmpl` | `.github/copilot-instructions.md` |
+| `cursor-mdc.tmpl` | `.cursor/rules/main.mdc` |
+| `windsurf.tmpl` | `.windsurf/rules/main.md` |
+| `junie.tmpl` | `.junie/guidelines.md` |
+| `continue.tmpl` | `.continue/rules/main.md` |
+| `gemini.tmpl` | `GEMINI.md` |
+| `aider-conventions.tmpl` | `CONVENTIONS.md` |
+| `aider-conf.tmpl` | `.aider.conf.yml` |
+| `replit.tmpl` | `replit.md` |
+
+Render: `_bridges/emit.sh <target-dir> [project-name] [project-description]`. Idempotent — existing files are skipped.
+
+Cross-ref: KeiAgent is the personal-CLI predecessor that also ships these templates (verified against vendor docs 2026-04).
diff --git a/_bridges/agents-md.tmpl b/_bridges/agents-md.tmpl
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+++ b/_bridges/agents-md.tmpl
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+# AGENTS.md
+
+> Read by Codex CLI (OpenAI spec), Copilot, Aider (when referenced), Windsurf, Warp, Zed, Antigravity (since v1.20.3, 2026-03-05), JetBrains Junie. See also: CLAUDE.md / .cursor/rules/ / GEMINI.md / .junie/guidelines.md / replit.md.
+
+## {{PROJECT_NAME}}
+
+{{PROJECT_DESCRIPTION}}
+
+## Before You Start
+1. Read `DECISIONS.md` — architectural choices already made
+2. Read `TODO.md` (if exists) — current priorities
+3. Read `CLAUDE.md` (if exists) — project-specific rules
+
+## Rules
+- **Constructor Pattern**: 1 file = 1 class. File <200 lines. Function <30 lines.
+- **Root cause**: fix causes, not symptoms
+- **SSOT**: types, routes, enums defined in ONE place
+- **Tests**: write WITH code, never defer
+
+## Do NOT
+- Rewrite working code without reason
+- Add abstractions for one-time operations
+- Skip reading DECISIONS.md before architectural changes
+- Commit .env, credentials, API keys
diff --git a/_bridges/aider-conf.tmpl b/_bridges/aider-conf.tmpl
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+# Aider config — auto-reads project rules on every session
+# See: https://aider.chat/docs/config/aider_conf.html
+read:
+  - CONVENTIONS.md
+  - AGENTS.md
diff --git a/_bridges/aider-conventions.tmpl b/_bridges/aider-conventions.tmpl
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+# {{PROJECT_NAME}} — Aider Conventions
+
+> Auto-loaded by Aider via `.aider.conf.yml` (`read: CONVENTIONS.md`).
+
+{{PROJECT_DESCRIPTION}}
+
+## Before You Start
+1. Read `DECISIONS.md` — architectural choices already made
+2. Read `TODO.md` (if exists) — current priorities
+3. Read `CLAUDE.md` (if exists) — project-specific rules
+
+## Constructor Pattern
+- 1 file = 1 class = 1 responsibility
+- File <200 lines, function <30 lines
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+
+## Core Rules
+- No patching — fix root cause, not symptoms
+- Don't rewrite working code without reason
+- Single Source of Truth — types, routes, enums in ONE place
+
+## Forbidden
+- Mixins, abstract factories, DI containers
+- Rewriting working code without reason
+- Committing .env, credentials, API keys
+- Adding abstractions for one-time operations
diff --git a/_bridges/continue.tmpl b/_bridges/continue.tmpl
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+++ b/_bridges/continue.tmpl
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+---
+name: {{PROJECT_NAME}}
+alwaysApply: true
+---
+
+# {{PROJECT_NAME}} — Continue.dev Rules
+
+{{PROJECT_DESCRIPTION}}
+
+## Constructor Pattern
+1 file = 1 class = 1 responsibility. Function >30 lines = split. File >200 lines = decompose.
+
+## Core Rules
+- No patching — fix root cause, not symptoms
+- Don't rewrite working code without reason
+- Single Source of Truth — types, routes, enums in ONE place
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+
+## Project Context
+- Architecture decisions: see `DECISIONS.md`
+- Project rules: see `CLAUDE.md`
+- Current priorities: see `TODO.md`
+
+## Forbidden
+- Mixins, abstract factories, DI containers
+- Rewriting working code without reason
+- Committing .env, credentials, API keys
+- Adding abstractions for one-time operations
diff --git a/_bridges/copilot.tmpl b/_bridges/copilot.tmpl
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+++ b/_bridges/copilot.tmpl
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+# {{PROJECT_NAME}} — Copilot Instructions
+
+## Architecture
+Read DECISIONS.md before making architectural choices. Document new decisions there.
+
+## Code Style
+- Constructor Pattern: 1 file = 1 class = 1 responsibility
+- File <200 lines, function <30 lines
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+
+## Forbidden
+- Mixins, abstract factories, DI containers
+- Rewriting working code without reason
+- Committing .env, credentials, API keys
+- Adding abstractions for one-time operations
diff --git a/_bridges/cursor-mdc.tmpl b/_bridges/cursor-mdc.tmpl
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+++ b/_bridges/cursor-mdc.tmpl
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+---
+description: {{PROJECT_NAME}} constructor-pattern coding rules
+globs: **/*
+alwaysApply: true
+---
+
+# {{PROJECT_NAME}} — Cursor Rules (MDC)
+
+{{PROJECT_DESCRIPTION}}
+
+## Constructor Pattern
+1 file = 1 class = 1 responsibility. Function >30 lines = split. File >200 lines = decompose.
+
+## Core Rules
+- No patching — fix root cause, not symptoms
+- Don't rewrite working code without reason
+- Single Source of Truth — types, routes, enums in ONE place
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+
+## Project Context
+- Architecture decisions: see `DECISIONS.md`
+- Project rules: see `CLAUDE.md`
+- Current priorities: see `TODO.md`
+
+## Forbidden
+- Mixins, abstract factories, DI containers
+- Rewriting working code without reason
+- Committing .env, credentials, API keys
+- Adding abstractions for one-time operations
+
+## Session Protocol
+- Read `DECISIONS.md` before making architectural choices
+- Document new decisions in `DECISIONS.md`
diff --git a/_bridges/cursorrules.tmpl b/_bridges/cursorrules.tmpl
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+++ b/_bridges/cursorrules.tmpl
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+# {{PROJECT_NAME}} — Cursor Rules
+
+## Constructor Pattern
+1 file = 1 class = 1 responsibility. Function >30 lines = split. File >200 lines = decompose.
+
+## Core Rules
+- No patching — fix root cause, not symptoms
+- Don't rewrite working code without reason
+- Single Source of Truth — types, routes, enums in ONE place
+- Root cause first — never fix symptoms
+
+## Project Context
+- Architecture decisions: see DECISIONS.md
+- Known issues: see TODO.md (if exists)
+
+## Code Style
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+- No mixins, no abstract factories, no DI containers
+
+## Session Protocol
+- Read DECISIONS.md before making architectural choices
+- Document new decisions in DECISIONS.md
diff --git a/_bridges/gemini.tmpl b/_bridges/gemini.tmpl
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+++ b/_bridges/gemini.tmpl
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+# {{PROJECT_NAME}} — Gemini / Antigravity Instructions
+
+> Primary memory file for Google Antigravity (also reads `AGENTS.md` since v1.20.3, 2026-03-05).
+
+{{PROJECT_DESCRIPTION}}
+
+## Before You Start
+1. Read `DECISIONS.md` — architectural choices already made
+2. Read `TODO.md` (if exists) — current priorities
+3. Read `CLAUDE.md` (if exists) — project-specific rules
+
+## Constructor Pattern
+- 1 file = 1 class = 1 responsibility
+- File <200 lines, function <30 lines
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+
+## Core Rules
+- No patching — fix root cause, not symptoms
+- Don't rewrite working code without reason
+- Single Source of Truth — types, routes, enums in ONE place
+
+## Forbidden
+- Mixins, abstract factories, DI containers
+- Rewriting working code without reason
+- Committing .env, credentials, API keys
+- Adding abstractions for one-time operations
diff --git a/_bridges/junie.tmpl b/_bridges/junie.tmpl
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+++ b/_bridges/junie.tmpl
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+# {{PROJECT_NAME}} — Junie Guidelines
+
+> Read by JetBrains Junie. Supplementary to `AGENTS.md` (Junie precedence: `.junie/AGENTS.md` > `AGENTS.md` > `.junie/guidelines.md`).
+
+{{PROJECT_DESCRIPTION}}
+
+## Before You Start
+1. Read `DECISIONS.md` — architectural choices already made
+2. Read `TODO.md` (if exists) — current priorities
+3. Read `CLAUDE.md` (if exists) — project-specific rules
+
+## Constructor Pattern
+- 1 file = 1 class = 1 responsibility
+- File <200 lines, function <30 lines
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+
+## Core Rules
+- No patching — fix root cause, not symptoms
+- Don't rewrite working code without reason
+- Single Source of Truth — types, routes, enums in ONE place
+
+## Forbidden
+- Mixins, abstract factories, DI containers
+- Rewriting working code without reason
+- Committing .env, credentials, API keys
+- Adding abstractions for one-time operations
diff --git a/_bridges/replit.tmpl b/_bridges/replit.tmpl
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+++ b/_bridges/replit.tmpl
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+# {{PROJECT_NAME}} — Replit Agent Instructions
+
+> Read by Replit Agent (does NOT read `AGENTS.md`).
+
+{{PROJECT_DESCRIPTION}}
+
+## Before You Start
+1. Read `DECISIONS.md` — architectural choices already made
+2. Read `TODO.md` (if exists) — current priorities
+3. Read `CLAUDE.md` (if exists) — project-specific rules
+
+## Constructor Pattern
+- 1 file = 1 class = 1 responsibility
+- File <200 lines, function <30 lines
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+
+## Core Rules
+- No patching — fix root cause, not symptoms
+- Don't rewrite working code without reason
+- Single Source of Truth — types, routes, enums in ONE place
+
+## Forbidden
+- Mixins, abstract factories, DI containers
+- Rewriting working code without reason
+- Committing .env, credentials, API keys
+- Adding abstractions for one-time operations
diff --git a/_bridges/windsurf.tmpl b/_bridges/windsurf.tmpl
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+++ b/_bridges/windsurf.tmpl
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+---
+trigger: always_on
+---
+
+# {{PROJECT_NAME}} — Windsurf Rules
+
+{{PROJECT_DESCRIPTION}}
+
+## Constructor Pattern
+1 file = 1 class = 1 responsibility. Function >30 lines = split. File >200 lines = decompose.
+
+## Core Rules
+- No patching — fix root cause, not symptoms
+- Don't rewrite working code without reason
+- Single Source of Truth — types, routes, enums in ONE place
+- Types/interfaces BEFORE implementation
+- Tests WITH code, never "later"
+
+## Project Context
+- Architecture decisions: see `DECISIONS.md`
+- Project rules: see `CLAUDE.md`
+- Current priorities: see `TODO.md`
+
+## Forbidden
+- Mixins, abstract factories, DI containers
+- Rewriting working code without reason
+- Committing .env, credentials, API keys
+- Adding abstractions for one-time operations
+
+## Session Protocol
+- Read `DECISIONS.md` before making architectural choices
+- Document new decisions in `DECISIONS.md`