docs: add US-EXT-001 for custom tools support

Author: sven1103

docs/user-stories.md

@@ -0,0 +1,89 @@
+# User Stories - Future Enhancements
+
+---
+
+## US-EXT-001 - Support Custom Tools in Configuration Bundles
+
+**Status**: Backlog  
+**Priority**: Medium  
+**Milestone**: v1.1.0 - Custom Tool Support
+
+### Background
+
+OpenCode supports custom tools defined in `.opencode/tools/` (see [Custom Tools Docs](https://opencode.ai/docs/custom-tools)). Tools are TypeScript/JavaScript definitions that can invoke scripts in any language.
+
+### User Story
+
+**As a**: bundle maintainer  
+**I want to**: include custom tools with my configuration presets  
+**So that**: agents can use specialized tooling beyond OpenCode's built-in tools
+
+### Acceptance Criteria
+
+1. Bundle manifest can optionally declare custom tools via a `tools` field
+2. Tool definitions are installed to `.opencode/tools/` in the target project
+3. Bundle manifest v1.1.0 is backward-compatible with v1.0.0 CLIs
+4. Documentation explains tool installation flow
+
+### Proposed Manifest Extension
+
+```json
+{
+  "manifest_version": 1,
+  "bundle_name": "qbic-opencode-config-bundle",
+  "bundle_version": "v1.1.0",
+  "presets": [...],
+  "tools": [
+    {
+      "name": "database",
+      "entrypoint": ".opencode/tools/database.ts",
+      "description": "Query the project database"
+    }
+  ]
+}
+```
+
+### Implementation Dependencies
+
+- CLI: Update manifest schema validation to accept optional `tools` field
+- CLI: Update `bundle apply` to copy tool definitions to `.opencode/tools/`
+- Bundle: Update manifest version to v1.1.0 when tools are added
+- Docs: Document tool installation flow
+
+### Notes
+
+- Tools are independent of agent prompts - prompts reference tools by name
+- Multiple tools can be defined in a single file or spread across files
+- Tool runtime can be Node.js, Python, or any system executable
+
+---
+
+## Future Extension Ideas
+
+### Tool Runtime Dependencies
+
+Future iterations could include dependency management for tools:
+
+```json
+{
+  "tools": [
+    {
+      "name": "database",
+      "entrypoint": ".opencode/tools/database.ts",
+      "runtime": "node",
+      "dependencies": ["pg", "dotenv"]
+    }
+  ]
+}
+```
+
+### Global vs Project Tools
+
+Future iterations could distinguish between:
+
+- **Project tools**: Installed per-project in `.opencode/tools/`
+- **Global tools**: Installed in `~/.config/opencode/tools/`
+
+---
+
+*Last updated: 2026-03-30*