Skill System

Skills provide specialized instructions and workflows for specific tasks. Agents can load skills on-demand to access domain-specific knowledge without bloating their base instructions.

Overview

Skills are Markdown documents containing:

Instructions - How to perform specific tasks
Tool catalogs - Available tools and their usage
Workflows - Step-by-step procedures
Best practices - Patterns and anti-patterns
Examples - Code snippets and configurations

Skill Catalog: apps/x/packages/core/src/application/assistant/skills/index.ts:1All available skills are registered in the catalog with IDs, titles, summaries, and content.

Available Skills

Web Search

ID: web-search
Use for: Searching the web or researching topics

Capabilities

Choosing between web-search (Brave) and research-search (Exa)
Understanding when to use each search tool
Guidelines on search frequency and quality
Category filtering for research-search

Key guidance:

Always start with exactly ONE search call
Never call multiple search tools simultaneously
Only make follow-up searches if truly necessary

Location: apps/x/packages/core/src/application/assistant/skills/web-search/skill.ts:1

Slack Integration

ID: slack
Use for: Sending messages, viewing channels, searching conversations

Capabilities

Checking Slack connection status
Listing users, channels, and DM conversations
Getting conversation history
Searching messages with Slack syntax
Sending messages to channels and DMs
Executing Slack actions via Composio
Complete tool catalog for all Slack operations

Key guidance:

Always check connection before using Slack tools
Show drafts before sending messages
Summarize channel history, don’t dump raw data
Cross-reference with knowledge base

Location: apps/x/packages/core/src/application/assistant/skills/slack/skill.ts:1

Background Agents

ID: background-agents
Use for: Creating, editing, and scheduling background agents

Capabilities

Agent file format (Markdown with YAML frontmatter)
Schedule configuration (cron, window, once)
Multi-agent workflow patterns
Tool type schemas (builtin, mcp, agent)
Schedule state management
Validation and best practices

Key guidance:

All agents are Markdown files in agents/ directory
“Workflows” are just agents that orchestrate other agents
Schedule configuration goes in agent-schedule.json
Never modify agent-schedule-state.json manually
Avoid executeCommand for background agents

Location: apps/x/packages/core/src/application/assistant/skills/background-agents/skill.ts:1

Builtin Tools Reference

ID: builtin-tools
Use for: Understanding and using builtin tools in agents

Capabilities

Complete executeCommand documentation
What can be done with shell commands
Agent-to-agent calling patterns
Copilot-specific builtin tools
File and directory operations
MCP operations (addMcpServer, listMcpTools, executeMcpTool)
When to use builtin vs MCP vs agent tools

Key guidance:

executeCommand is the most powerful builtin tool
Commands are filtered through security.json
Agents can call other agents as tools
Copilot has access to workspace and MCP operations

Location: apps/x/packages/core/src/application/assistant/skills/builtin-tools/skill.ts:1

MCP Integration

ID: mcp-integration
Use for: Discovering and executing MCP tools

Capabilities

Always check MCP tools first before declining tasks
MCP server configuration schemas (stdio vs http)
Using addMcpServer tool with validation
Discovering available servers and tools
Executing MCP tools directly (copilot)
Schema matching for tool execution
Adding MCP tools to agents

Key guidance:

ALWAYS check listMcpServers before saying “I can’t do that”
Use addMcpServer tool, never manually edit mcp.json
Carefully examine inputSchema before executing tools
Common servers: firecrawl, filesystem, github, fetch, time

Location: apps/x/packages/core/src/application/assistant/skills/mcp-integration/skill.ts:1

Document Collaboration

ID: doc-collab
Use for: Creating, editing, and refining documents Collaborate on documents in the knowledge base - create notes, edit content, and refine documentation. Location: apps/x/packages/core/src/application/assistant/skills/doc-collab/skill.ts

Draft Emails

ID: draft-emails
Use for: Processing emails and creating responses Process incoming emails and create draft responses using calendar and knowledge base context. Location: apps/x/packages/core/src/application/assistant/skills/draft-emails/skill.ts

Meeting Prep

ID: meeting-prep
Use for: Preparing for meetings Gather context about meeting attendees from the knowledge base and prepare briefing documents. Location: apps/x/packages/core/src/application/assistant/skills/meeting-prep/skill.ts

Organize Files

ID: organize-files
Use for: Finding and organizing files Find, organize, and tidy up files on the user’s machine. Move files to folders, clean up Desktop/Downloads, locate specific files. Location: apps/x/packages/core/src/application/assistant/skills/organize-files/skill.ts

Create Presentations

ID: create-presentations
Use for: Creating PDF presentations and slide decks Create PDF presentations and slide decks from natural language requests using knowledge base context. Location: apps/x/packages/core/src/application/assistant/skills/create-presentations/skill.ts

Deletion Guardrails

ID: deletion-guardrails
Use for: Following safe deletion procedures Follow the confirmation process before removing workflows, agents, and their dependencies. Location: apps/x/packages/core/src/application/assistant/skills/deletion-guardrails/skill.ts

Skill Loading

Resolve Skill

Skills are resolved by ID or file path:

import { resolveSkill } from "@x/core/skills";

// By ID
const skill = resolveSkill("web-search");

// By path (many variants supported)
const skill = resolveSkill("skills/web-search/skill.ts");
const skill = resolveSkill("src/application/assistant/skills/web-search/skill.ts");

Supported Path Formats

The resolver accepts many path variants:

web-search
web-search/skill
web-search/skill.ts
web-search/skill.js
skills/web-search/skill.ts
src/application/assistant/skills/web-search/skill.ts
Absolute paths (resolved from CURRENT_DIR)

Both .ts and .js extensions are accepted.

Location: apps/x/packages/core/src/application/assistant/skills/index.ts:180

Skill Catalog

Get a formatted list of all skills:

import { skillCatalog } from "@x/core/skills";

console.log(skillCatalog);

Output:

# Rowboat Skill Catalog

Use this catalog to see which specialized skills you can load.

## Create Presentations
- **Skill file:** `src/application/assistant/skills/create-presentations/skill.ts`
- **Use it for:** Create PDF presentations and slide decks from natural language requests

## Document Collaboration
- **Skill file:** `src/application/assistant/skills/doc-collab/skill.ts`
- **Use it for:** Collaborate on documents - create, edit, and refine notes

...

Location: apps/x/packages/core/src/application/assistant/skills/index.ts:111

Using Skills in Agents

Copilot loadSkill Tool

The copilot can load skills dynamically using the loadSkill builtin tool:

tools:
  loadSkill:
    type: builtin
    name: loadSkill

Usage:

// Load skill by ID
await loadSkill({ identifier: "web-search" });

// Load skill by path
await loadSkill({ 
  identifier: "src/application/assistant/skills/web-search/skill.ts" 
});

The skill content is injected into the conversation context, providing specialized guidance for the current task.

When to Load Skills

Load skills proactively when:

User asks for a task matching a skill’s domain
You need specialized knowledge for a complex operation
User mentions specific tools or services (Slack, MCP, etc.)
Creating or modifying agents with specific tool types
Debugging or troubleshooting domain-specific issues

// User: "Search the web for latest AI news"

// 1. Load web-search skill
await loadSkill({ identifier: "web-search" });

// 2. Follow skill guidance to choose tool
// Skill says: Use web-search (Brave) for current events

// 3. Execute tool
await webSearch({ query: "latest AI news" });

// User: "Can you search the web?"

// 1. Load mcp-integration skill
await loadSkill({ identifier: "mcp-integration" });

// 2. Follow skill guidance to check MCP tools
await listMcpServers();
await listMcpTools({ serverName: "firecrawl" });

// 3. Execute MCP tool
await executeMcpTool({
  serverName: "firecrawl",
  toolName: "firecrawl_search",
  arguments: { query: "latest AI news" }
});

// User: "Create a daily email digest agent"

// 1. Load background-agents skill
await loadSkill({ identifier: "background-agents" });

// 2. Follow skill guidance for agent structure
// - Create task-specific agents
// - Create orchestrator agent
// - Schedule in agent-schedule.json

// 3. Create agent files with proper format
await workspaceWriteFile({
  path: "agents/email_reader.md",
  content: "---\nmodel: gpt-5.1\n..."
});

Skill Architecture

Skill Definition

type SkillDefinition = {
  id: string;              // Skill identifier
  title: string;           // Display name
  summary: string;         // Short description
  content: string;         // Full Markdown content
};

Location: apps/x/packages/core/src/application/assistant/skills/index.ts:18

Resolved Skill

type ResolvedSkill = {
  id: string;              // Skill identifier
  catalogPath: string;     // Path in catalog
  content: string;         // Full Markdown content
};

Location: apps/x/packages/core/src/application/assistant/skills/index.ts:25

Skill Registration

Skills are registered in the catalog with multiple path aliases:

const definitions: SkillDefinition[] = [
  {
    id: "web-search",
    title: "Web Search",
    summary: "Searching the web or researching topics",
    content: webSearchSkill
  },
  // ... more skills
];

// Register with multiple aliases
for (const entry of skillEntries) {
  const aliases = [
    entry.id,
    `${entry.id}/skill`,
    `${entry.id}/skill.ts`,
    `skills/${entry.id}/skill.ts`,
    `src/application/assistant/skills/${entry.id}/skill.ts`,
    absolutePath
  ];
  
  for (const alias of aliases) {
    registerAliasVariants(alias, resolvedEntry);
  }
}

Location: apps/x/packages/core/src/application/assistant/skills/index.ts:31

Creating Custom Skills

To add a new skill:

Create skill file - apps/x/packages/core/src/application/assistant/skills/my-skill/skill.ts

export const skill = String.raw`
# My Skill

Description of what this skill provides.

## When to Use

Load this skill when...

## Available Tools

### tool-name
Description and usage...

## Workflows

Step-by-step procedures...

## Best Practices

Patterns and anti-patterns...

## Examples

Code snippets and configurations...
`;

export default skill;

Import in index - apps/x/packages/core/src/application/assistant/skills/index.ts

import mySkill from "./my-skill/skill.js";

const definitions: SkillDefinition[] = [
  // ... existing skills
  {
    id: "my-skill",
    title: "My Skill",
    summary: "Short description of my skill",
    content: mySkill
  }
];

Use in agents - Load dynamically or include in instructions

await loadSkill({ identifier: "my-skill" });

Best Practices

Skill Design

Focus on specific domains - Each skill should cover one area deeplyProvide concrete examples - Show exact code, commands, and configurationsInclude workflows - Step-by-step procedures for common tasksDocument edge cases - Cover error handling and troubleshootingKeep updated - Maintain skills as tools and APIs evolve

Skill Usage

Load proactively - Don’t wait for the agent to get stuckLoad multiple skills - Complex tasks may need several skillsFollow skill guidance - Skills provide tested patternsUpdate context - Reload skills if requirements change

Skill Organization

Modular structure - Keep skills focused and composableClear naming - Use descriptive IDs and titlesComprehensive summaries - Help agents choose the right skillVersion considerations - Note compatibility and dependencies

Next Steps

Agent Overview

Learn about agent system architecture

Runtime

Explore agent execution details

Background Agents

Understand scheduled execution

Overview

CLI Tool

Python SDK

Web Platform

Agent System

Overview

Available Skills

Web Search

Slack Integration

Background Agents

Builtin Tools Reference

MCP Integration

Document Collaboration

Draft Emails

Meeting Prep

Organize Files

Create Presentations

Deletion Guardrails

Skill Loading

Resolve Skill

Skill Catalog

Using Skills in Agents

Copilot loadSkill Tool

When to Load Skills

Skill Architecture

Skill Definition

Resolved Skill

Skill Registration

Creating Custom Skills

Best Practices

Next Steps

Agent Overview

Runtime

Background Agents

​Overview

​Available Skills

​Web Search

​Slack Integration

​Background Agents

​Builtin Tools Reference

​MCP Integration

​Document Collaboration

​Draft Emails

​Meeting Prep

​Organize Files

​Create Presentations

​Deletion Guardrails

​Skill Loading

​Resolve Skill

​Skill Catalog

​Using Skills in Agents

​Copilot loadSkill Tool

​When to Load Skills

​Skill Architecture

​Skill Definition

​Resolved Skill

​Skill Registration

​Creating Custom Skills

​Best Practices

​Next Steps

Agent Overview

Runtime

Background Agents

Overview

Available Skills

Web Search

Slack Integration

Background Agents

Builtin Tools Reference

MCP Integration

Document Collaboration

Draft Emails

Meeting Prep

Organize Files

Create Presentations

Deletion Guardrails

Skill Loading

Resolve Skill

Skill Catalog

Using Skills in Agents

Copilot loadSkill Tool

When to Load Skills

Skill Architecture

Skill Definition

Resolved Skill

Skill Registration

Creating Custom Skills

Best Practices

Next Steps